This results in faster rates of glycogen storage and provides the body with enough glucose to initiate the recovery process Burke et al. Muscle glycogen stores are replenished the fastest within the first hour after exercise. Consuming carbohydrate within an hour after exercise also helps to increase protein synthesis Gibala, The Growth Phase The growth phase consists of the 18 - 20 hours post-exercise when muscle repair, growth and strength occur.

According to authors Ivy and Portman, the goals of this phase are to maintain insulin sensitivity in order to continue to replenish glycogen stores and to maintain the anabolic state.

Consuming a protein and carbohydrate meal within 1 - 3 hours after resistance training has a positive stimulating effect on protein synthesis Volek, Carbohydrate meals with moderate to high glycemic indexes are more favorable to enhance post-exercise fueling.

Higher levels of glycogen storage post-exercise are found in individuals who have eaten high glycemic foods when compared to those that have eaten low glycemic foods Burke et al. Nutrient Timing Supplement Guidelines: Putting it Together for Yourself and Your Clients Aquatic instructors expend a lot of energy in teaching and motivating students during multi-level fitness classes.

Clearly, nutrient timing may be a direction the aquatic profession may choose to pursue to determine if it provides more energy and faster recovery from a challenging teaching load. As well, some students and clients may seek similar results.

From the existing research, here are some recommended guidelines of nutrient timing. Energy Phase During the energy phase a drink consisting of high-glycemic carbohydrate and protein should be consumed.

This drink should contain a ratio of carbohydrate to protein and should include approximately 6 grams of protein and 24 grams of carbohydrate.

Additional drink composition substances should include leucine for protein synthesis , Vitamin C and E because they reduce free-radical levels-which are a contributing cause to muscle damage , and sodium, potassium and magnesium which are important electrolytes lost in sweat.

Anabolic Phase During the anabolic phase a supplement made up of high-glycemic carbohydrate and protein should be consumed. This should be a ratio of carbohydrate to protein and should contain approximately 15 g of protein and 45 grams of carbohydrate. Other important drink substances include leucine for protein synthesis , glutamine for immune system function , and antioxidant Vitamins C and E.

Growth Phase There are two segments of the growth phase. The first is a rapid segment of muscle repair and growth that lasts for up to 4 hours.

The second segment is the remainder of the day where proper nutrition guidelines are being met complex carbohydrates, less saturated fats--substituting with more monounsatureated and polyunsaturated fats, and healthy protein sources such as chicken, seafood, eggs, nuts, lean beef and beans.

During the rapid growth phase a drink filled with high-glycemic carbohydrates and protein may be consumed. In this phase the ratio of carbohydrates to protein should be with 4 grams of carbohydrate to 20 grams of protein. However, the information and discussion in this article better prepares the aquatic fitness professional to guide and educate students about the metabolic and nutrient needs of exercising muscles.

In the areas of nutrition and exercise physiology, nutrient timing is 'buzzing' with scientific interest. Ingestion of appropriate amounts of carbohydrate and protein at the right times will enhance glycogen synthesis, replenish glycogen stores, decrease muscle inflammation, increase protein synthesis, maintain continued muscle cell insulin sensitivity, enhance muscle development, encourage faster muscle recovery and boost energy levels…that says it all.

References: Bell-Wilson, J. The Buzz About Nutrient Timing. IDEA Fitness Journal, Burke, L. Carbohydrates and fat for training and recovery. Journal of Sports Sciences, 22, Caffeine elimination appears to fluctuate over the course of the menstrual cycle with slower elimination and more pronounced effects during the LP as well as with OC use [ 82 ].

The accumulation of caffeine during this high-estrogen phase may magnify premenstrual symptoms, as well as intensify the sympathetic effects of caffeine, resulting in increased heart rate, anxiety, and impaired sleep [ 83 , 84 , 85 ]. It should be noted that studies to date evaluating the effects of caffeine in women have not accounted for the menstrual cycle.

Teacrine is a naturally occurring purine alkaloid that is similar to caffeine. It is most commonly found in tea and coffee, and acts as an adenosine receptor antagonist, as well as supporting a positive benefit on mood and energy [ 88 ], without negatively affecting tolerance.

The half-life of teacrine is 2 h and it has been shown to be safe and effective for delaying fatigue, both physically and cognitively [ 89 ]. The combined effects of caffeine and teacrine may be a unique combinatory approach for increasing energy and delaying fatigue in women, but more female-specific research with teacrine is warranted.

Dietary nitrate supplementation has attracted substantial interest over the past decade for its role in health and athletic performance. Nitrate products are thought to increase NO production through the NO synthase-dependent pathway of NO production, which includes a series of reactions oxidizing l -arginine to l -citrulline and NO.

Specifically, NO is a potent signaling molecule that elicits changes in biological and physiological processes such as vasodilation, mitochondrial efficiency, and calcium handling, all of which have important implications for exercise capacity [ 90 ]. Sex-based differences in physiology and biological processes may influence NO production [ 91 ].

Compared with male individuals, female individuals have higher baseline NO levels and may have greater increases in NO following nitrate supplementation, although this is largely influenced by dosing [ 91 ]. Additionally, the effects of nitrate supplementation appear to be more effective in early post-menopausal women for supporting improvements in blood pressure [ 92 ], compared with premenopausal women, which highlights the impact of estrogen on endothelial tissues.

Women have demonstrated increased blood flow during intermittent exercise. However, female individuals have smaller vessels indicating they may be more likely to benefit from nitrate intake particularly as it relates to vasodilation. Female individuals also have a greater ability to reduce nitrates to NO compared with male individuals, suggesting nitrate supplementation may be more effective in women compared with men [ 91 ].

Supplementation with nitrates may be particularly important for aerobic activities and for delaying fatigue during exercise, as well as in women as they age. Additionally, mL of beetroot juice consumed 2. The impact of dietary nitrate supplementation on recovery or across the menstrual cycle has not yet been explored in women.

Dietary nitrates are most commonly found in green leafy vegetable and root vegetables, and dietary supplementation forms of nitrates include beetroot juice and pomegranate extract as well as citrulline and arginine.

Dosing and timing recommendations are provided in Table 1 [ 94 ]. The importance of carbohydrate availability for exercise performance is well established [ 95 ]. As a result of sex-based differences that exist in carbohydrate and fat oxidation during exercise [ 22 ], as well as differing sensitivities of the gastrointestinal tract among active women [ 96 ], carbohydrate supplementation during exercise is ergogenic [ 95 ].

As noted in Sect. The intricacies and practicalities of this are previously described [ 19 ]. In concert with carbohydrate feeding during exercise, symptoms of gastrointestinal distress have been reported to be more prevalent in female endurance athletes, and among those women consuming hypotonic beverages [ 97 ].

Other forms of carbohydrate supplementation may be important to consider for active women, particularly for women undergoing endurance exercise. Modified starches may affect the gastric-emptying rate, enhancing glycogen storage, [ 98 ] which may be beneficial during the FP, or to spare glycogen by enhancing fat oxidation, which may also be beneficial as estrogen and progesterone levels change.

To date, research has failed to demonstrate a positive effect of a fast-digesting high-molecular-weight starch in female cyclists [ 99 ] or a slow-digesting modified starch [ 98 ]. There are some potential positive data for modified starch on performance, but only in men.

This area needs additional study but addressing and modifying the carbohydrate source may be helpful for the active woman undergoing exercise activities that rely on muscle glycogen, as well as to mitigate gastrointestinal distress.

The benefits of creatine supplementation for women are growing in evidence, with positive benefits related to strength, hypertrophy, performance, as well as energetic and cognitive outcomes [ ].

Creatine kinase modulations have also been shown to align with the cyclical pattern of estrogen across the menstrual cycle [ ]. Fluctuations in creatine kinase levels have been reported to be influenced by endogenous hormones, with the lowest levels observed during non-menstruating years, and subsequent decreases with age and pregnancy [ ].

Creatine supplementation may be particularly effective post-partum as a result of cellular energy depletion surrounding childbirth [ ]. Decreases in muscle mass, bone mass, and muscle strength, resulting from decreased estrogen levels observed during the menopause transition, have also shown to be attenuated with creatine supplementation [ , ].

Short-term and long-term creatine supplementation have shown significant beneficial ergogenic outcomes in strength, hypertrophy, and exercise performance in trained and untrained female populations when compared with placebo controls [ ].

Mechanisms supporting increases in strength, hypertrophy, and performance are likely related to increased intramuscular phosphocreatine stores, which allow for a greater stimulus of training through greater energy availability from increased ATP turnover during exercise. Delayed neuromuscular fatigue allows for improved recovery and prevention of fatigue through maintenance of pH [ ].

Data also suggest positive relationships between mood and severity of depressive episodes with creatine and phosphocreatine levels in the brain [ ]. Research has demonstrated a reduced time for acclimatization of anti-depressant medications for expedited effectiveness with creatine supplementation [ ].

Creatine supplementation has also shown to effectively reduce mental fatigue and improve cognitive performance, specifically during times of high duress or impacted sleep quantity or quality [ ].

A common misconception surrounding creatine supplementation pertains to undesirable weight gain in women; however, research shows initial gains incurred with loading doses are likely a result of increased cellular hydration i. Currently, evidence shows consistent recommended dosage amounts for male and female individuals.

Our essential fatty acids, omega 6 and omega 3, are key modulators of cell function, lipid-soluble vitamin absorption, and lipid metabolism. Irrefutable evidence has demonstrated a significant reduction in the risk of cardiovascular disease with an increase in omega 3 fatty acids [ ].

This is particularly relevant for women, as the risk of cardiovascular disease is exacerbated as they transition to menopause. The two most active eicosanoids derived from omega 3 are eicosapentaenoic acid and docosahexaenoic acid, which play a vital role in improving immune function and aid in growth and development [ ].

Existing literature has demonstrated improved inflammatory environments following omega 3 supplementation, including arthritis, inflammatory bowel disease, and asthma.

This may be particularly beneficial during the FP of the menstrual cycle when systemic inflammation is elevated. Essential fats are also needed to prevent and counteract relative energy deficiency syndrome [ ].

Other potential benefits from elevated omega 3 intake include a decrease in muscle soreness as a result of reducing inflammation [ ], increased muscle protein synthesis by stimulating the mechanistic target of rapamycin complex 1 pathway [ ], and improved bone health [ ].

For women who demonstrate greater anabolic resistance [ ], this could be efficacious. Additionally, increased levels of omega 3 have been shown to reduce symptoms of depression and anxiety [ ], which are reported in higher rates in women versus men. Benefits of omega 3 have been reported when 1—3 g daily are consumed [ , ].

Nootropics have gained even more traction among active women during the coronavirus disease pandemic. With women participating in greater more effective multi-tasking and invisible work [ ], nootropics may support better cognition and memory. While this is not meant to be an exhaustive literature review, the following ingredients may be beneficial to support cognition in the active woman.

Rhodiola rosea has been shown to reduce fatigue, improve exercise time to exhaustion, as well as improve mood with — mg daily [ , ]. Some of the research is mixed using Rhodiola , which is likely attributed to the varying integrity of rosavins.

L-theanine is a non-proteinic amino acid that can cross the blood—brain barrier, resulting in improved attention, particularly with individuals with reported anxiety [ ]. L-theanine is often combined with caffeine; positive effects have been demonstrated with — mg dosages.

Citicoline has demonstrated cognitive-enhancing and neuroprotective properties in pre-clinical and clinical studies.

Following 28 days of citicoline supplementation mg and mg in middle-aged women, there was a significant improvement in attention [ ]. Including a nootropic ingredient when formulating or choosing dietary supplements for active women is supported by increasing evidence, particularly if they are experiencing sleep deprivation, anxiety, and brain fog.

Vitamin D is traditionally known for its pivotal role in calcium absorption. However, it is also imperative for innate and acquired immune system regulation, skeletal muscle function, bone absorption, and possible prevention of disease [ ].

Research suggests that as women age, vitamin D levels decrease with the highest rate of vitamin D deficiency occurring in post-menopausal women [ ].

For active women, vitamin D levels could directly affect muscle strength and performance, recovery from exercise, and bone health. Furthermore, vitamin D deficiency has been shown to increase the risk of anemia, which is highly prevalent among active women [ ].

Therefore, vitamin D supplementation is recommended for women across the lifespan and across all activity levels. Additionally, a focus on dietary vitamin D through foods such as fish, cheese, and some cereals is an important consideration for women [ ].

Vitamin D is fat soluble, which means it needs to be consumed with at least one serving of fat. Minerals, such as magnesium, are essential inorganic elements necessary for most metabolic processes. Magnesium activates enzymes involved in protein synthesis, is involved in ATP reactions, and may improve energy metabolism [ ].

Acute changes in plasma magnesium levels are noticeable during a continuous bout of moderate-to-high intensity exercise [ 94 ]. There is growing evidence to support an essential role of magnesium in various physiological outcomes for women as they age [ ]. Normal serum magnesium levels range between 0.

Overall, magnesium deficiency in healthy individuals consuming a balanced diet is rare, but dosing requirements may change in response to hormonal variations and training adaptations.

Specifically, there are various pathophysiological conditions across the female lifespan, such as use of OCs, pregnancy, and menopause, that may increase magnesium requirements Fig. Magnesium supplementation in pre-menopausal women may improve premenstrual syndrome symptoms through decreasing inflammatory markers [ ].

In peri-menopausal to post-menopausal women, magnesium supplementation may be protective for bone health through optimization of the vitamin D status [ ]. Additionally, as women traverse through menopause, there is an increased risk for hypertension.

Emerging data suggest magnesium has an inverse relationship with hypertension risk, suggesting magnesium supplementation may have cardioprotective benefits [ ], especially for women.

The recommended dietary allowance for magnesium in women is — mg per day, but magnesium supplementation may be needed if the recommended dietary allowance is not met through the diet alone. Magnesium-rich foods include nuts, almonds, bananas, black beans, brown rice, cashews, spinach, seeds, and whole grains Table 2.

Considerations for magnesium intake across the female lifespan and for factors influencing magnesium deficiency. The gastrointestinal tract of a woman begins to differ from a man at the onset of puberty and continues to change with hormonal fluctuations [ ].

Early evidence suggests that women have lower intestinal permeability and higher microbial diversity but are more sensitive to perturbation [ ]. Women also have reported greater symptoms of irritable bowel syndrome and symptoms of leaky gut, particularly with exercise.

Probiotics have been shown to be an effective stimulus for promoting bacterial diversity and targeting many aspects of health [ , ]. Probiotic supplementation has been shown to improve intestinal function and reduce inflammation, which may be effective for modulating changes in inflammation during the FP.

Probiotics in women have also resulted in improved absorption of iron, when combined with iron supplementation, which could help to reduce iron-deficient anemia, as well as enhance the absorption of some amino acids, which may enhance MPS [ , ]. Evidence also suggests probiotic use in women may effectively reduce the reoccurrence of urinary tract infections [ , ].

A multi-strain probiotic supplement is likely the most feasible approach to see the most benefit. Women have unique and changeable hormone profiles that influence their physiology and nutritional needs.

Evidence supports the use of female-specific ingredients to optimize body composition, delay fatigue, and improve mental and physical health.

Future research and product development must include women across the lifespan and begin to expand upon their needs to improve health, quality of life, and performance.

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Fast twitch fibres may predict anaerobic performance in both females and males. Int J Sports Med. Russ DW, Lanza IR, Rothman D, Kent-Braun JA. Sex differences in glycolysis during brief, intense isometric contractions.

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The effect of the menstrual cycle and oral contraceptive cycle on muscle performance and perceptual measures.

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Oxidative stress in female athletes using combined oral contraceptives. Sports Med Open. Gruber CJ, Tschugguel W, Schneeberger C, Huber JC. Production and actions of estrogens. N Engl J Med. Van Pelt RE, Gavin KM, Kohrt WM. Regulation of body composition and bioenergetics by estrogens.

Endocrinol Metab Clin N Am. Ambikairajah A, Walsh E, Tabatabaei-Jafari H, Cherbuin N. Fat mass changes during menopause: a metaanalysis. Am J Obstet Gynecol. Day DS, Gozansky WS, Van Pelt RE, Schwartz RS, Kohrt WM. Sex hormone suppression reduces resting energy expenditure and β-adrenergic support of resting energy expenditure.

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Metabolic effects of menopause: a cross-sectional characterization of body composition and exercise metabolism. Fujita S, Rasmussen BB, Bell JA, Cadenas JG, Volpi E. Basal muscle intracellular amino acid kinetics in women and men. Am J Physiol Endocrinol Metab. Miller BF, Hansen M, Olesen JL, Flyvbjerg A, Schwarz P, Babraj JA, et al.

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We suggest focusing on vitamins D, B6, and minerals like zinc and magnesium. One study found that daily vitamin D supplementation for one year resulted in a significant increase in total, bioactive, and free testosterone levels in men with initial vitamin D deficiency. We can obtain vitamin D from sunlight exposure, certain foods fatty fish, egg yolks, and mushrooms , or supplementation.

This vitamin helps regulate hormonal balance in the body, which can positively affect testosterone levels. One study found that regular supplementation of Vitamin B6 is a good way to make sure your testosterone levels stay elevated. Another study found that a deficiency in Vitamin B6 leads to a decreased rate of testosterone synthesis.

Vitamin B6 can be found in foods such as chicken, fish, and whole grains. This essential mineral plays a critical role in testosterone production. Severe and moderate zinc deficiencies are associated with hypogonadism, a low testosterone condition, in men.

Zinc supplementation may increase testosterone levels , but only if the body is deficient in zinc. Consuming zinc-rich foods such as oysters, beef, nuts, and seeds can help with this. Magnesium is another important mineral that can potentially boost testosterone levels.

One study found that magnesium supplementation can help return testosterone levels to normal if the cause of the decrease is a deficiency. Another study found that taking magnesium supplements for at least 1 month might increase testosterone in all people.

We should aim to consume magnesium-rich foods like leafy greens, legumes, and whole grains. A balanced intake of protein and carbohydrates about hours pre-workout can curb a significant drop in hormone levels, maintaining an elevated testosterone state during training. Consider snacks that combine a protein source with complex carbohydrates.

This combination provides sustained energy and aids muscle preservation, both vital for testosterone production. Consuming a balanced meal or snack within minutes post-workout can maximize muscle repair, glycogen replenishment, and testosterone production.

Beyond exercise-related nutrient timing, consistently consuming testosterone-boosting nutrients throughout the day is crucial. Consider this example of a daily meal plan that supports testosterone production:. In our quest to increase testosterone naturally, we should not overlook the importance of sleep and recovery.

Our bodies repair and rejuvenate during sleep, which is essential for maintaining optimal hormone levels. Aim for at least hours of quality sleep per night, and make it a priority to follow a consistent sleep schedule. Stress is another significant factor that can adversely impact testosterone levels.

Elevated cortisol, the primary stress hormone, can suppress testosterone production. Therefore, we must effectively manage stress to optimize hormone balance.

Regular physical activity is crucial for maintaining overall health and vitality, which in turn supports hormone balance. Ideally, we should incorporate both aerobic and resistance training into our workouts, as these activities have been shown to positively influence testosterone levels.

It can be a game-changer in planning and monitoring your macronutrient ratios and meal timing, which are key strategies for boosting testosterone levels. All of your macro and micronutrient targets in Cronometer are customizable, so first, ensure those align with your goals.

Log your food, then check your Daily Report to ensure you hit all your macro and micronutrient targets. Gold users can leverage our timestamps feature, which can be beneficial in helping you adhere to regular meal intervals.

In conclusion, nutrient timing can significantly contribute to naturally enhancing testosterone levels. However, it requires a comprehensive understanding of macronutrients, micronutrients, and meal frequency, paired with a consistent and mindful application of these principles.

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From a historical perspective, nutrient timing was first conceptualized in the s and s with the initial work that examined the effects of increased carbohydrate feedings on glycogen status and exercise performance [ 2 , 3 ]. Ivy and colleagues [ 4 ] were one of the first groups to illustrate that carbohydrate timing can influence post-exercise rates of glycogen resynthesis.

While strategies surrounding carbohydrates were the first to be explored, there has been a growing body of research over the last several years that has examined the effect of protein and amino acids, with and without carbohydrates, as a nutrient timing strategy [ 1 , 5 ].

Due to the volume of research investigating this concept, the need to revise and update the original document is evident. In line with the previous publication, the updated version focuses on timing considerations for two macronutrients: carbohydrates and proteins.

When considering fat, research examining a specific timing question has yet to take shape. As researchers continue to explore the manipulation of fat and carbohydrate intake e. It is exciting to note that new research has begun to examine the impact of timed calcium a micronutrient intake on its ability to affect markers of bone resorption during prolonged cycling exercise [ 7 , 8 , 9 , 10 ] and animal models have explored the potential role of timing iron intake on various health-related outcomes [ 11 , 12 ].

This research, however, is in its infancy and more studies are needed to better understand these implications.

For instance, research related to caffeine [ 13 ], creatine [ 14 , 15 , 16 ] and bicarbonate [ 17 ] have indicated that timing may affect the acute and chronic response to exercise. Therefore, the primary purpose of this updated position stand is to refine recommendations made related to the timed consumption of carbohydrates and protein and how this can potentially affect the adaptive response to exercise.

To expand upon the previous version, the current position stand now discusses research and recommendations related to meal patterns, timing, and distribution of protein, meal frequency and nighttime eating. It is the contention of the ISSN that these topics also fall under the purview of nutrient timing.

Additionally, non-athletic or specialized clinical populations may also derive benefit from these strategies. Throughout each section, an attempt has been made to first highlight outcomes from acute studies before discussing those derived from training studies spanning several weeks or more.

Moderate to high intensity e. It is well documented that glycogen stores are limited [ 18 , 19 ] and operate as a predominant source of fuel for up to a few hours during moderate to high-intensity aerobic exercise e.

Importantly, as glycogen levels decline, the ability of an athlete to maintain exercise intensity and work output also decreases [ 19 ] while rates of tissue breakdown increase [ 23 , 24 ]. The simplest guideline to maximize endogenous glycogen stores is for a high-performance athlete to ingest appropriate amounts of carbohydrate relative to their intensity and volume of training.

In the absence of considerable muscle damage, this carbohydrate intake level has been shown to maximize glycogen storage.

It should be noted that most of the recommendations for carbohydrate intake are based on the needs of endurance athletes, and in particular, male endurance athletes. Moreover, studies have indicated that trained female athletes do not oxidize fat and carbohydrate at the same rates as males and may deplete endogenous glycogen stores to different degrees [ 28 , 29 , 30 , 31 ].

Perhaps those involved in strength-power sports need a lower intake of carbohydrate and instead should focus more on prioritizing their carbohydrate intake in the days leading up to competition, but more research is required as this topic has been critically evaluated in a review by Escobar et al.

It should be noted that athletes often fail to meet recommended amounts of energy and carbohydrate; consequently [ 33 ], strategies to replenish carbohydrate stores may take priority toprepare for maximal performance in the next competition.

Sherman and colleagues [ 2 , 34 ] also demonstrated success at maximizing intramuscular glycogen stores using similar approaches. Alternatively, Bussau et al. A similar approach by Fairchild et al. Overall, the ability of carbohydrate loading strategies to rapidly increase and maximize muscle glycogen levels is currently unquestioned, and many athletes and coaches are encouraged to consider making use of such a dietary regimen in the days leading up to a competitive event, particularly if their activity will significantly deplete endogenous skeletal muscle glycogen.

The hours leading up to competition are often a highly prioritized period of feeding and studies have indicated that strategic fuel consumption can help to maximize muscle and liver glycogen levels.

Carbohydrate feedings during this time increase endogenous glycogen stores while also helping to maintain blood glucose levels.

Notably, Coyle et al. In addition to increasing stored glycogen, other studies have reported significant improvements in aerobic exercise performance [ 37 , 38 , 39 ].

However, not all studies have demonstrated a performance-enhancing effect. Additionally, and as a measure of practical importance, the need to ingest a pre-exercise meal or snacks high in carbohydrate goes up when the athlete has consumed relatively small amounts of carbohydrate in the days leading up to a competition or has not allowed for appropriate amounts of rest and recovery [ 20 , 24 ].

In this respect, another priority becomes maintaining a favorable balance with the digestive system and avoiding the consumption of too much food or fluid before competition. Practically speaking, many endurance events begin in the early morning hours and finding an adequate balance between rest and fuel must be considered.

In this respect, two studies have reported that solid or liquid forms of carbohydrates similarly promote glycogen resynthesis allowing athletes more flexibility when selecting food sources [ 40 , 41 ]. A certain degree of dogma still clouds the recommendation to ingest certain types of carbohydrate, or avoid carbohydrate altogether, in the final few hours before an event.

From these findings, it has been surmised that excessive carbohydrate consumption, and in particular fructose consumption, in the initial hours before exercise may negatively impact exercise performance perhaps due to rebound hypoglycemia.

Indeed, given the rise in insulin due to carbohydrate ingestion coupled with up-regulation of GLUT-4 transporters from the initiated exercise stimulus, there may be a decrease, rather than increase, in blood glucose at the onset of activity that could negatively impact performance.

However, while a number of athletes may be affected by this phenomenon, a study by Moseley et al. A review by Hawley and Burke summarized the results of several studies that provided some form of carbohydrate at least 60 min before exercise.

They found no adverse impact on performance. Moreover, Galloway and colleagues [ 45 ] used a double-blind, placebo-controlled approach to compare performance outcomes related to ingestion of a placebo or a 6.

Ingesting carbohydrate 30 min before exercise led to greater increases in exercise capacity. They concluded that performance was similar for both types of carbohydrate. The delivery of carbohydrate remains a priority once a workout or competition commences. Several studies have indicated that the pattern or timing of carbohydrate feedings surrounding endurance exercise may be important.

For example, Fielding and colleagues [ 50 ] required cyclists to ingest the same dose of carbohydrate every 30 min or every 60 min over the course of a four-hour exercise bout. When carbohydrate was ingested more frequently, performance was improved. Two contrasting papers that operate as extensions of this work include work by Schweitzer et al.

It is important to realize that key differences such as the duration of the exercise bout, the nature of the performance assessment fixed distance vs. time-to-exhaustion and amount of carbohydrate that was delivered all differed between these studies and can help to explain the differences in outcomes being reported.

A classic paper by Widrick et al. Increased power outputs were recorded when exercise began with high muscle glycogen levels, and even greater power was achieved when carbohydrate was frequently provided throughout the exercise protocol.

The four feeding conditions were: a placebo beverage 30 min before and a 6. As with the findings of Widrick et al. Collectively, these findings somewhat prioritize carbohydrate feeding during the exercise session and could lead some to argue that if pre-exercise carbohydrate feeding strategies are neglected, then delivering appropriate carbohydrate throughout an exercise bout may help offset the potential for performance decrement.

However, one must cautiously explore this approach as to avoid overwhelming the gastrointestinal system potentially leading to cramping and discomfort once exercise begins.

In this respect one should consider the findings of Newell et al. Importantly, no differences in performance were found between these two feeding strategies suggesting that for those athletes who may not be able to tolerate higher doses of carbohydrates, a moderate regimen of carbohydrate feeding throughout a prolonged bout of exercise can still promote similar improvements in performance.

Other important considerations related to the potential ergogenic impact of carbohydrates have been critically highlighted in recent reviews by Colombani et al. In both papers, the authors contend that the ability of carbohydrate administration during bouts of exercise spanning less than 70 min to operate in an ergogenic fashion is largely mixed in the literature.

Whether or not these results translate to intermittent sports remains to be thoroughly investigated. A review by Phillips and colleagues [ 58 ] supports the notion that carbohydrate administration throughout intermittent, team-sport activities improves certain types of performance as well as general indicators of mental drive and acuity, but evidence regarding benefits of acute deviations in timing is still lacking.

No performance or capacity measurements were made, but the authors did report that either feeding pattern was able to maintain glucose, insulin, glycerol, non-esterified fatty acid, and epinephrine levels.

More recently, Mizuno and colleagues [ 60 ] concluded that timing the intake of a carbohydrate gel 1. The recovery of lost muscle glycogen operates as a key nutritional goal, and post-exercise ingestion of carbohydrate continues to be a popular and efficient nutrient timing strategy to maximize replenishment of lost muscle glycogen.

Subsequent work has since refined conclusions surrounding this topic, namely that the timing of post-exercise carbohydrate administration holds the highest level of importance under two primary situations: 1 when rapid restoration of muscle glycogen is a primary goal and 2 when inadequate amounts of carbohydrate are being delivered.

In light of these considerations, muscle glycogen levels can be rapidly and maximally restored using an aggressive post-exercise feeding regimen of carbohydrates. Ingesting 0. Similarly, favorable outcomes have also been shown when 1.

Outside of situations where rapid recovery is truly needed, and daily carbohydrate intake is matching energy demands, the importance of timed carbohydrate ingestion is notably decreased. However, in no situation has timed carbohydrate ingestion been shown to negatively impact performance or recovery.

If an athlete participating in heavy exercise is not able, or even not sure if they will be able to appropriately consume the required amounts of carbohydrate throughout the day then the strategically timed ingestion of carbohydrate may accelerate muscle glycogen re-synthesis.

When prolonged endurance exercise is completed, carbohydrate ingestion may also help promote a favorable hormonal environment [ 65 , 66 ].

Studies employing resistance exercise that examined some aspect of carbohydrate timing are limited. Multiple studies have demonstrated that resistance exercise can significantly decrease muscle glycogen concentration [ 22 , 68 , 69 , 70 ], though these decreases are modest in comparison to exhaustive endurance exercise.

However, the provision of pre-exercise carbohydrate to individuals performing resistance-style exercise in a moderately glycogen depleted state may not have an ergogenic effect.

To date, one study has indicated that carbohydrate administration before and during bouts of resistance exercise can improve performance, but these ergogenic outcomes were only seen in the second session of resistance exercise performed on the same day [ 71 ]. In contrast, multiple studies have failed to report an improvement in resistance exercise performance [ 72 , 73 , 74 ].

One study involving pre-exercise and during exercise delivery of carbohydrate throughout a bout of resistance exercise has been shown to minimize the loss of muscle glycogen. Briefly, study participants were given a carbohydrate dose of 1.

Athletes are encouraged to continue consuming small amounts of a carbohydrate solution or small snacks bars, gels, etc. to maintain liver glycogen levels and to help prevent hypoglycemia.

Ingestion of carbohydrate during endurance type exercise maintains blood glucose levels, spares glycogen [ 75 ], and will likely enhance performance.

Post-exercise consumption of carbohydrate is necessary and in situations where minimal recovery time is available, aggressive carbohydrate feeding is recommended. Although preliminary, initial work in intermittent, high-intensity activities suggest that carbohydrate timing may support metabolic outcomes, while performance results remain mixed, as do studies involving resistance exercise.

For further inquiry, excellent reviews on the topic of carbohydrate and performance are available [ 20 , 21 , 48 , 49 , 76 ]. In a crossover fashion, participants ingested either a 7. When protein was added to carbohydrate, endurance was significantly improved. The same research group [ 79 ] used a nutrient gel and again reported that ingestion of a carbohydrate 0.

Furthermore, the addition of protein to carbohydrate has been shown to increase the speed of glycogen recovery when a short recovery window is available or if sub-optimal amounts of carbohydrate have been delivered and can also help to reduce symptoms of muscle damage [ 80 ]. Notably, no studies have demonstrated that addition of protein to carbohydrate to a pre-exercise feeding in these amounts may hinder exercise performance.

Similarly, Rustad and colleagues [ 81 ] reported that adding protein 0. To support recovery upon completion of exercise bouts that can deplete stored fuels and may cause significant damage to the muscle tissue, post-exercise nutrient timing strategies are of great interest.

Ivy et al. These findings replicated previous findings [ 83 ] by this research group and led them to conclude that the addition of protein favorably promoted early phases of glycogen recovery.

Berardi et al. As more research has been completed on the topic, the potential benefits of adding protein have been questioned. For example, Jentjens and colleagues [ 63 ] failed to show an improvement in muscle glycogen restoration with a combination of carbohydrate 1.

Howarth and colleagues [ 86 ] later came to a similar conclusion regarding the addition of protein and extended these findings also to report that a higher dose of carbohydrate 1. For example, Kraemer and colleagues [ 87 ] had participants ingest a combination of carbohydrate, protein, and fat or an isoenergetic maltodextrin placebo for seven days before two consecutive days of resistance exercise.

Moreover, markers of muscle damage e. A few years later, however, Fujita and colleagues [ 90 ] attempted to replicate their study findings and instead determined that MPS rates were similar between pre-exercise and post-exercise ingestion.

While many people use the Fujita paper to discount the pre-exercise period, it should be noted that significant increases in MPS rates occurred when nutrients were administered before and after the resistance training bout in comparison to a non-energetic control suggesting that nutrient delivery itself , as opposed to timing of delivery, should be a larger priority.

A later study by Bird et al. Using a crossover study design, participants also ingested a placebo that consisted of water flavored with a non-nutritive sweetener in similar volumes at the same times. They reported that delivering nutrients versus none at all did significantly increase the volume of exercise completed and reduced concentrations of serum proteins indicative of muscle damage.

Bird et al. While these findings are encouraging, the studies are limited by the dosage of EAA provided as other studies have indicated that higher EAA doses up to 12 g may maximally stimulate MPS.

As such, future research in this area should identify if different doses of EAA or combining a carbohydrate solution with varying doses of intact proteins consumed during resistance exercise bouts can further impact performance and resistance training adaptations.

In this respect, when sufficient protein is supplied, it may be that carbohydrate has no additional adaptive benefit. As an example of this, Hulmi and colleagues [ 97 ] showed no benefit in resistance training adaptations when a combination of maltodextrin carbohydrate Changes in strength, hypertrophy, and body composition were assessed, and significant increases in lean body mass, 1RM strength, type II muscle fiber cross-sectional area, and higher muscle creatine and glycogen levels were found when the supplements were consumed immediately before and after workouts as opposed to consuming them in the morning and evening.

Furthermore, Cribb and Hayes also provided creatine while the other studies did not, which has been shown in multiple investigative scenarios to augment the muscular adaptations seen while resistance training [ 98 , 99 , ]. Specifically, insulin promotes anti-catabolic effects in muscle [ ], thereby shifting protein balance to favor anabolism.

This would suggest that post-workout carbohydrate supplementation likely exerts minimal influence from a muscle development standpoint provided adequate protein is consumed. However, when optimal carbohydrate is delivered the impact of adding protein irrespective of when it is provided appears to offer little to no additional benefit on endurance or resistance exercise performance as well as the recovery of reduced muscle glycogen.

Much like the work on glycogen recovery, studies involving resistance training and optimization of adaptations seen from resistance training also point towards a higher priority being given towards the total amount of protein consumed during the day.

Therefore, if total protein needs are met, the importance of adding carbohydrate and even more so in a timed fashion may be limited. A key point of discussion, however, lies with whether or not total energy needs are also being met, particularly in athletes undergoing large volumes of training and more so in those athletes that have high amounts of lean as well as body mass.

In these situations, it certainly remains possible that the addition of carbohydrate to a protein feeding may help the athlete achieve an appropriate energy intake, which certainly may go on to impact the extent to which adaptations occur.

In response to EAA ingestion and independent of leucine content, MPS rates and several signaling proteins related to muscle hypertrophy i. were significantly increased. While more research certainly needs to be conducted to better identify the potential impact and role of protein intake before endurance exercise, the priority for an endurance athlete in the hours leading up to competition should be focused on appropriate carbohydrate intake to fully maximize endogenous production of glycogen.

As with endurance exercise, the majority of studies that have employed some form of protein or amino acid ingestion before bouts of resistance exercise have done so in conjunction with an identical dose during the post-exercise period as well. For example, Tipton and colleagues [ ] used an acute resistance exercise and feeding model to report that MPS rates were similar when a g dose of whey protein was ingested immediately before or immediately after a bout of lower body resistance training.

Andersen et al. In this study, participants were randomized to ingest either 25 g of a protein blend In the group that consumed the protein-amino acid blend, type I and type II muscle fibers experienced a significant increase in size.

Also, the protein-amino acid group experienced a significant increase in squat jump height while no changes occurred in the carbohydrate group. Using a similar study design, Hoffman and colleagues [ ] had collegiate football players who had been regularly performing resistance-training ingest 42 g of hydrolyzed collagen protein either immediately before and immediately after exercise, or in the morning and evening over the course of ten weeks of resistance training.

In this study, the timing of protein intake did not impact changes in strength, power and body composition experienced from the resistance-training program. When examining the discrepant findings, one must consider a few things.

First, the protein source in the Hoffman et al. study was mostly a collagen hydrolysate i. Finally, the study participants in the Andersen et al.

More recently, Schoenfeld and colleagues [ ] published the first longitudinal study to directly compare the effects of ingesting 25 g of whey protein isolate either immediately before or immediately after each workout.

This study is significant as it is the first investigation to attempt to compare pre versus post-workout ingestion of protein. The authors raised the question that the size, composition, and timing of a pre-exercise meal may impact the extent to which adaptations are seen in these studies.

However, a key limitation of this investigation is the very limited training volumes these subjects performed. The total training sessions over the week treatment period was 30 sessions i. One would speculate that the individuals who would most likely benefit from peri-workout nutrition are those who train at much higher volumes.

For instance, American collegiate athletes per NCAA regulations NCAA Bylaw 2. Thus, the average college athlete trains more in two weeks than most subjects train during an entire treatment period in studies in this category. In one of the only studies to use older participants, Candow and colleagues [ 15 ] assigned 38 men between the ages of 59—76 years to ingest a 0.

While protein administration did favorably improve resistance-training adaptations, the timing of protein before or after workouts did not invoke any differential change. An important point to consider with the results of this study is the sub-optimal dose of protein approximately 26 g of whey protein versus the known anabolic resistance that has been demonstrated in the skeletal muscle of elderly individuals [ ].

In this respect, the anabolic stimulus from a g dose of whey protein may not have sufficiently stimulated muscle protein synthesis or have been of appropriate magnitude to induce differences between conditions.

Clearly, more research is needed to determine if a greater dose of protein delivered before or after a workout may exert an impact on adaptations seen during resistance training in an elderly population.

Limited studies are available that have examined the effect of providing protein throughout an acute bout of resistance exercise, particularly studies designed to explicitly determine if protein administration during exercise was more favorable than other times of administration.

However, when examined over the course of 12 weeks, the increases in fiber size seen after ingesting a solution containing 6 g of EAA alone was less than when it was combined with carbohydrate [ 96 ]. The post-exercise time period has been aggressively studied for its ability to heighten various training outcomes.

While a large number of acute exercise and nutrient administration studies have provided multiple mechanistic explanations for why post-exercise feeding may be advantageous [ , , , , ], other studies suggest this study model may not be directly reflective of adaptations seen over the course of several weeks or months [ ].

As highlighted throughout the pre-exercise protein timing section, the majority of studies that have examined some aspect of post-exercise protein timing have done so while also administering an identical dose of protein immediately before each workout [ 16 , , , ].

These results, however, are not universal as Hoffman et al. Of note, participants in the Hoffman study were all highly-trained collegiate athletes who reported consuming a hypoenergetic diet.

Candow et al. As mentioned previously, it is possible that the dose of protein may not have been an appropriate amount to properly stimulate anabolism. In this respect, a small number of studies have examined the impact of solely ingesting protein after exercise.

As discussed earlier, Tipton and colleagues [ ] used an acute model to determine changes in MPS rates when a g bolus of whey protein was ingested immediately before or immediately after a single bout of lower-body resistance training.

MPS rates were significantly, and similarly, increased under both conditions. Until recently, the only study that examined the effects of post-exercise protein timing in a longitudinal manner was the work of Esmarck et al.

In this study, 13 elderly men average age of 74 years consumed a small combination of carbohydrates 7 g , protein 10 g and fat 3 g either immediately within 30 min or 2 h after each bout of resistance exercise done three times per week for 12 weeks. Changes in strength and muscle size were measured, and it was concluded that ingesting nutrients immediately after each workout led to greater improvements in strength and muscle cross-sectional area than when the same nutrients were ingested 2 h later.

While interesting, the inability of the group that delayed supplementation but still completed the resistance training program to experience any measurable increase in muscle cross-sectional area has led some to question the outcomes resulting from this study [ 5 , ].

Further and as discussed previously with the results of Candow et al. Schoenfeld and colleagues [ ] published results that directly examined the impact of ingesting 25 g of whey protein immediately before or immediately after bouts of resistance-training.

All study participants trained three times each week targeting all major muscle groups over a week period, and the authors concluded no differences in strength and hypertrophy were seen between the two protein ingestion groups.

These findings lend support to the hypothesis that ingestion of whey protein immediately before or immediately after workouts can promote improvements in strength and hypertrophy, but the time upon which nutrients are ingested does not necessarily trump other feeding strategies. Reviews by Aragon and Schoenfeld [ ] and Schoenfeld et al.

The authors suggested that when recommended levels of protein are consumed, the effect of timing appears to be, at best, minimal. Indeed, research shows that muscles remain sensitized to protein ingestion for at least 24 h following a resistance training bout [ ] leading the authors to suggest that the timing, size and composition of any feeding episode before a workout may exert some level of impact on the resulting adaptations.

In addition to these considerations, recent work by MacNaughton and colleagues [ ] reported that the acute ingestion of a g dose versus g of whey protein resulted in significantly greater increases in MPS in young subjects who completed an intense, high volume bout of resistance exercise that targeted all major muscle groups.

Notwithstanding these conclusions, the number of studies that have truly examined a timing question is rather scant. Moreover, recommendations must capture the needs of a wide range of individuals, and to this point, a very small number of studies have examined the impact of nutrient timing using highly trained athletes.

From a practical standpoint, some athletes may struggle, particularly those with high body masses, to consume enough protein to meet their required daily needs. As a starting point, it is important to highlight that most of the available research on this topic has largely used non-athletic, untrained populations except two recent publications using trained men and women [ , ].

Whether or not these findings apply to highly trained, athletic populations remains to be seen. Changes in weight loss and body composition were compared, and slightly greater weight loss occurred when the majority of calories was consumed in the morning.

As a caveat to what is seemingly greater weight loss when more calories are shifted to the morning meals, higher amounts of fat-free mass were lost as well, leading to questions surrounding the long-term efficacy of this strategy regarding weight management and metabolic activity.

Notably, this last point speaks to the importance of evenly spreading out calories across the day and avoiding extended periods of time where no food, protein in particular, is consumed.

A large observational study [ ] examined the food intake of free-living individuals males and females ,and a follow-up study from the same study cohort [ ] reported that the timing of food consumption earlier vs.

later in the day was correlated to the total daily caloric intake. Wu and colleagues [ ] reported that meals later in the day lead to increased rates of lipogenesis and adipose tissue accumulation in an animal model and, while limited, human research has also provided support.

Previously it has been shown that people who skip breakfast display a delayed activation of lipolysis along with an increase in adipose tissue production [ , ]. More recently, Jakubowicz and colleagues [ ] had overweight and obese women consume cal each day for a week period.

Approximately 2. While these results provide insight into how calories could be more optimally distributed throughout the day, a key perspective is that these studies were performed in sedentary populations without any form of exercise intervention. Thus, their relevance to athletes or highly active populations might be limited.

Furthermore, the current research approach has failed to explore the influence of more evenly distributed meal patterns throughout the day. Meal frequency is commonly defined as the number of feeding episodes that take place each day. For years, recommendations have indicated that increasing meal frequency may serve as an effective way to influence weight loss, weight maintenance, and body composition.

These assertions were based upon the epidemiological work of Fabry and colleagues [ , ] who reported that mean skinfold thickness was inversely related to the frequency of meals. One of these studies involved overweight individuals between 60 and 64 years of age while the other investigation involved 80 participants between the ages of 30—50 years of age.

An even larger study published by Metzner and colleagues [ ] reported that in a sample of men and women between 35 and 60 years of age, meal frequency and adiposity were inversely related. While intriguing, the observational nature of these studies does not agree with more controlled experiments.

For example, a study by Farshchi et al. The irregular meal pattern was found to result in increased levels of appetite, and hunger leading one to question if the energy provided in each meal was inadequate or if the energy content of each meal could have been better matched to limit these feelings while still promoting weight loss.

Furthermore, Cameron and investigators [ ] published what is one of the first studies to directly compare a greater meal frequency to a lower frequency. In this study, 16 obese men and women reduced their energy intake by kcals per day and were assigned to one of two isocaloric groups: one group was instructed to consume six meals per day three traditional meals and three snacks , while the other group was instructed to consume three meals per day for an eight-week period.

Changes in body mass, obesity indices, appetite, and ghrelin were measured at the end of the eight-week study, and no significant differences in any of the measured endpoints were found between conditions.

These results also align with more recent results by Alencar [ ] who compared the impact of consuming isocaloric diets consisting of two meals per day or six meals per day for 14 days in overweight women on weight loss, body composition, serum hormones ghrelin, insulin , and metabolic glucose markers.

No differences between groups in any of the measured outcomes were observed. A review by Kulovitz et al. Similar conclusions were drawn in a meta-analysis by Schoenfeld and colleagues [ ] that examined the impact of meal frequency on weight loss and body composition.

Although initial results suggested a potential advantage for higher meal frequencies on body composition, sub-analysis indicated that findings were confounded by a single study, casting doubt as to whether the strategy confers any beneficial effects. From this, one might conclude that greater meal frequency may, indeed, favorably influence weight loss and body composition changes if used in combination with an exercise program for a short period of time.

Certainly, more research is needed in this area, particularly studies that manipulate meal frequency in combination with an exercise program in non-athletic as well as athletic populations.

Finally, other endpoints related to meal frequency i. may be of interest to different populations, but they extend beyond the scope of this position stand. An extension of altering the patterns or frequency of when meals are consumed is to examine the pattern upon which protein feedings occur.

Moore and colleagues [ ] examined the differences in protein turnover and synthesis rates when participants ingested different patterns, in a randomized order, of an g total dose of protein over a h measurement period following a bout of lower body resistance exercise.

One of the protein feeding patterns required participants to consume two g doses of whey protein isolate approximately 6 h apart. Another condition required the consumption of four, g doses of whey protein isolate every 3 h.

The final condition required the participants to consume eight, g doses of whey protein isolate every 90 min. Rates of muscle protein turnover, synthesis, and breakdown were compared, and the authors concluded that protein turnover and synthesis rates were greatest when intermediate-sized g doses of whey protein isolate were consumed every 3 h.

One of the caveats of this investigation was the very low total dose of protein consumed. Eighty grams of protein over a h period would be grossly inadequate for athletes performing high volumes of training as well as those who are extremely heavy e. A follow-up study one year later from the same research group determined myofibrillar protein synthesis rates after randomizing participants into three different protein ingestion patterns and examined how altering the pattern of protein administration affected protein synthesis rates after a bout of resistance exercise [ ].

Two key outcomes were identified. First, rates of myofibrillar protein synthesis rates increased in all three groups. Second, when four, g doses of whey protein isolate were consumed every 3 h over a h post-exercise period, significantly greater in comparison to the other two patterns of protein ingestion rates of myofibrillar protein synthesis occurred.

In combining the results of both studies, one can conclude that ingestion of intermediate protein doses 20 g consumed every 3 h creates more favorable changes in both whole-body as well as myofibrillar protein synthesis [ , ].

Although both studies employed short-term methodology and other patterns or doses have yet to be examined, the results thus far consistently suggest that the timing or pattern in which high-quality protein is ingested may favorably impact net protein balance as well as rates of myofibrillar protein synthesis.

An important caveat to these findings is that supplementation in most cases was provided in exclusion of other macronutrients over the duration of the study. Consumption of mixed meals delays gastric emptying and thus may result in different metabolic effects.

Moreover, the fact that whey is a fast-absorbing protein source [ ] further confounds the ability to generalize results to traditional mixed-meal diets, as the potential for oxidation is increased with larger dosages, particularly in the absence of other macronutrients.

Whether acute MPS responses translate to longitudinal changes in hypertrophy or fiber composition also remains to be determined [ ]. Protein pacing involves the consumption of 20—40 g servings of high-quality protein, from both whole food and protein supplementation, evenly spaced throughout the day, approximately every 3 h.

The first meal is consumed within 60 min of waking in the morning, and the last meal is eaten within 3 h of going to sleep at night. Arciero and colleagues [ , ] have most recently demonstrated increased muscular strength and power in exercise-trained physically fit men and women using protein pacing compared to ingestion of similar sized meals at similar times but different protein contents, both of which included the same multi-component exercise training during a week intervention.

In support of this theory one can point to the well characterized changes seen in peak MPS rates within 90 min after oral ingestion of protein [ ] and the return of MPS rates to baseline levels in approximately 90 min despite elevations in serum amino acid levels [ ].

Thus if efficacious protein feedings are placed too close together it remains possible that the ability of skeletal muscle anabolism to be fully activated might be limited.

While no clear consensus exists as to the acceptance of this theory, conflicting findings exist between longitudinal studies that did provide protein feedings in close proximity to each other [ 16 , , ], making this an area that requires more investigation.

Finally, while the mechanistic implications of pulsed vs. bolus protein feedings and their effect on MPS rates may help ultimately guide application, the practical importance has yet to be demonstrated. Eating before sleep has long been controversial [ , , ]. However, methodological considerations in the original studies such as the population used, time of feeding, and size of the pre-sleep meal confounds any conclusions that can be drawn.

Recent work using protein-centric beverages consumed min before sleep and 2 h after the last meal dinner have identified pre-sleep protein consumption as advantageous to MPS, muscle recovery, and overall metabolism in both acute and long-term studies [ , ]. For example, data indicate that 30—40 g of casein protein ingested min prior to sleep [ ] or via nasogastric tubing [ ] increased overnight MPS in both young and old men, respectively.

Likewise, in an acute setting, 30 g of whey protein, 30 g of casein protein, and 33 g of carbohydrate consumption min pre-sleep resulted in elevated morning resting metabolic rate in fit young men compared to a non-caloric placebo [ ].

Of particular interest is that Madzima et al. This infers that casein protein consumed pre-sleep maintains overnight lipolysis and fat oxidation. This finding was verifiedwhen Kinsey et al.

It was concluded that pre-sleep casein did not blunt overnight lipolysis or fat oxidation. Similar to Madzima et al.

Of note, it appears that previous exercise training completely ameliorates any rise in insulin when eating at night before sleep [ ] and the combination of pre-sleep protein and exercise has been shown to reduce blood pressure and arterial stiffness in young obese women with prehypertension and hypertension [ ].

To date, only two studies involving nighttime protein have been carried out for longer than four weeks. Snijders et al. The group receiving the protein-centric supplement each night before sleep had greater improvements in muscle mass and strength over the weeks.

Of note, this study was non-nitrogen balanced and the protein group received approximately 1. More recently, in a nitrogen-balanced design using young healthy men and women, Antonio et al.

All subjects maintained their usual exercise program. The authors reported no differences in body composition or performance between the morning and evening casein supplementation groups. A potential explanation for the lack of findings might stem from the already high intake of protein by the study participants before the study commenced.

However, it is worth noting that although not statistically significant, the morning group added 0. Thus, it appears that protein consumption in the evening before sleep represents another opportunity to consume protein and other nutrients.

Certainly more research is needed to determine if timing per se, or the mere addition of total daily protein can affect body composition or recovery via nighttime feeding. Nutrient timing is an area of research that continues to gather interest from researchers, coaches, and consumers.

In reviewing the literature, two key considerations should be made. First, all findings surrounding nutrient timing require appropriate context because factors such as age, sex, fitness level, previous fueling status, dietary status, training volume, training intensity, program design, and time before the next training bout or competition can influence the extent to which timing may play a role in the adaptive response to exercise.

Second, nearly all research within this topic requires further investigation. The reader must keep in perspective that in its simplest form nutrient timing is a feeding strategy that in nearly all situations may be helpful towards the promotion of recovery and adaptations towards training.

This context is important because many nutrient timing studies demonstrate favorable changes that do not meet statistical thresholds of significance thereby leaving the reader to interpret the level of practical significance that exists from the findings.

It is noteworthy that differences in real-world athletic performances can be so small that even strategies that offer a modicum of benefit are still worth pursuing. In nearly all such situations, this approach results in an athlete receiving a combination of nutrients at specific times that may be helpful and has not yet shown to be harmful.

This perspective also has the added advantage of offering more flexibility to the fueling considerations a coach or athlete may employ.

Using this approach, when both situations timed or non-timed ingestion of nutrients offer positive outcomes then our perspective is to advise an athlete to follow whatever strategy offers the most convenience or compliance if for no other reason than to deliver vital nutrients in amounts at a time that will support the physiological response to exercise.

Finally, it is advisable to remind the reader that due to the complexity, cost and invasiveness required to answer some of these fundamental questions, research studies often employ small numbers of study participants.

Also, for the most part studies have primarily evaluated men. This latter point is particularly important as researchers have documented that females oxidize more fat when compared to men, and also seem to utilize endogenous fuel sources to different degrees [ 28 , 29 , 30 ].

Furthermore, the size of potential effects tends to be small, and when small potential effects are combined with small numbers of study participants, the ability to determine statistical significance remains low.

Nonetheless, this consideration remains relevant because it underscores the need for more research to better understand the possibility of the group and individual changes that can be expected when the timing of nutrients is manipulated.

In many situations, the efficacy of nutrient timing is inherently tied to the concept of optimal fueling. Thus, the importance of adequate energy, carbohydrate, and protein intake must be emphasized to ensure athletes are properly fueled for optimal performance as well as to maximize potential adaptations to exercise training.

High-intensity exercise particularly in hot and humid conditions demands aggressive carbohydrate and fluid replacement. Consumption of 1. The need for carbohydrate replacement increases in importance as training and competition extend beyond 70 min of activity and the need for carbohydrate during shorter durations is less established.

Adding protein 0. Moreover, the additional protein may minimize muscle damage, promote favorable hormone balance and accelerate recovery from intense exercise.

For athletes completing high volumes i. The use of a 20—g dose of a high-quality protein source that contains approximately 10—12 g of the EAA maximizes MPS rates that remain elevated for three to four hours following exercise.

Protein consumption during the peri-workout period is a pragmatic and sensible strategy for athletes, particularly those who perform high volumes of exercise. Not consuming protein post-workout e. The impact of delivering a dose of protein with or without carbohydrates during the peri-workout period over the course of several weeks may operate as a strategy to heighten adaptations to exercise.

Like carbohydrate, timing related considerations for protein appear to be of lower priority than the ingestion of optimal amounts of daily protein 1. In the face of restricting caloric intake for weight loss, altering meal frequency has shown limited effects on body composition.

However, more frequent meals may be more beneficial when accompanied by an exercise program. The impact of altering meal frequency in combination with an exercise program in non-athlete or athlete populations warrants further investigation.

It is established that altering meal frequency outside of an exercise program may help with controlling hunger, appetite and satiety. Nutrient timing strategies that involve changing the distribution of intermediate-sized protein doses 20—40 g or 0. One must also consider that other factors such as the type of exercise stimulus, training status, and consumption of mixed macronutrient meals versus sole protein feedings can all impact how protein is metabolized across the day.

When consumed within 30 min before sleep, 30—40 g of casein may increase MPS rates and improve strength and muscle hypertrophy. In addition, protein ingestion prior to sleep may increase morning metabolic rate while exerting minimal influence over lipolysis rates.

In addition, pre-sleep protein intake can operate as an effective way to meet daily protein needs while also providing a metabolic stimulus for muscle adaptation.

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The Hormone Diet is a 6-week, three-step process designed to promote hormonal balance and an overall healthier body through diet, exercise, nutritional supplements, and detoxification. The diet regulates what you eat and also tells you the right time to eat to ensure maximum benefit to your hormones.

The book boasts of being the first diet book to emphasize the importance of hormonal balance among all the hormones that influence weight. It also claims to be the first to explain the lifestyle habits that can help boost hormones to burn fat.

These include:. The diet aims for weight loss of up to 12 pounds, including water weight, in the first phase.

It aims for about 2 pounds a week after that without calorie counting. According to the author, following the entire protocol may help you optimize the levels of inflammation in your body as well as these hormones:.

This phase also involves taking nutritional supplements. These include probiotics and anti-inflammatory products, like turmeric and fish oil. In this phase, you incorporate some foods back into your diet while paying attention to how your body responds to them. The Mediterranean diet is a heart-healthy diet modeled after the traditional, olive oil-rich diet eaten in the Mediterranean 1 , 2.

The third phase focuses on entire physical and mental wellness through cardiovascular exercise and strength training. The diet plan of the second phase continues on into the third phase. You would likely lose weight on The Hormone Diet. Two of the key goals of The Hormone Diet are to reduce inflammation and insulin resistance, both of which are associated with obesity 3 , 4.

They are more calorie dense, and they may also indeed cause dysfunctions in hunger hormones that lead to weight gain 5 , 6. Highly processed foods may contribute to insulin resistance, a condition in which the body starts to ignore the hormone insulin — which helps regulate blood sugar levels.

This can lead to weight gain as insulin levels increase to compensate for their diminished effectiveness since insulin also triggers fat storage 7.

Consider limiting them in your diet whenever possible. The diet takes a solid stance on weight loss and overall health, promoting natural, nutritious foods and regular exercise. Also, the focus on mental health, stress management, and adequate sleep are all important components that can help you optimize your health, and that may also have effects on body weight-regulating hormones.

For example, high levels of the hormone cortisol are linked to increased abdominal fat. Cortisol is known as the stress hormone because it becomes elevated with stress. Focusing on mental health, improving your sleep, and managing your stress may help reduce cortisol levels.

However, you would need to have your cortisol tested before and after to know for sure 8. It also de-emphasizes the importance of counting calories, which may make it seem more freeing than other diet programs for some people.

It encourages you to eat often to prevent excessive hunger, and to eat to satiety. Even without following The Hormone Diet specifically, eating whole and nutritious foods, limiting processed foods, and getting regular exercise will help you manage your weight not only in the immediate future but also long term.

However, there are some downsides to The Hormone Diet. Its focus on timing and testing may be unnecessarily burdensome for certain people. Some people might not be able to keep up with a schedule of eating in intervals and constantly paying attention to their hormones.

Having hormones tested is a complicated process that requires visits to the doctor, blood draws, and saliva tests. It costs both money and time. Additionally, The Hormone Diet recommends several dietary supplements and advocates for only consuming organic meat and organic coffee.

The cost of these items can add up, placing a financial burden on some people.