Purchase in season fruit, which is more flavorful and less expensive, than fruit that is out of season. The USDA has a Seasonal Produce Guide that can assist you with selecting seasonal fruits and vegetables to enjoy.

Similar to fruits, select an array of colors and types of vegetables to enjoy with your meals and snacks. Leafy greens, colorful bell peppers, summer squash, zucchini, cherry tomatoes, baby carrots, and cucumbers are all great options. Keep frozen vegetables on hand to have as a quick side dish with a meal or to add into soups, pastas, and stir-fry meals.

Beans are a nutritious option, providing an excellent source of fiber and also protein. Keep a variety of beans on hands including: black beans, garbanzo beans, navy beans, lima beans, kidney beans, and soy beans. Edamame type of soybean is a complete protein containing all of the essential amino acids.

Edamame can be a great snack, topping on a salad, or high-protein, nutritious side item to enjoy with your meal. Athletes should focus on including whole grain carbohydrates in their sports nutrition meal plan. Whole grains provide fiber, vitamins, minerals, and antioxidants.

Select whole grain items such as quinoa, brown rice, oatmeal, and whole wheat bread, pastas, tortillas, and wraps. Athletes should make healthy choices when selecting snacks for the day. Snacks are often associated with items such as candy, chips, and baked goods.

It can be helpful for athletes to change their perception of snacks and view them as an opportunity to provide your body with important nutrients needed to support your sports nutrition goals.

One way to do this is to focus on how you build your snacks. Aim for each snack to include a source of lean protein plus a healthy option from one other food group.

Example healthy snack ideas for athletes include:. You can find additional ideas and tips for packing snacks in my blog Healthy Snacks for Teenage Athletes. Be mindful when dining out to make choices that are in line with your sports nutrition goals. The concepts discussed previously regarding sugar-sweetened beverages, portion sizes, and healthy cooking methods all apply to eating out.

When possible, select a restaurant that has healthy options available. Additional tips for dining out healthfully include:. It is important for athletes to avoid drastic cuts in calories and severe energy restriction when attempting to lose weight.

Athletes should consider meeting with a sports dietitian nutritionist if they desire to change your body composition or lose weight. A sports dietitian nutritionist can assist the athlete with developing a customized meal plan to help them achieve their sports nutrition goals.

You are now set with 10 strategies to support athletes with achieving their weight loss goals. As a reminder, it is best for athletes to focus on sustainable changes to their dietary patterns during the off-season, which can lead to long-term success. For additional sports nutrition tips for athletes, check out my blog Meal Prep for Athletes: 5 Easy Steps to Success.

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Saarni SE, Rissanen A, Sarna S, Koskenvuo M, Kaprio J: Weight cycling of athletes and subsequent weight gain in middleage. Article CAS Google Scholar. Download references. Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Fetzer Hall CB , Chapel Hill, NC, , USA.

You can also search for this author in PubMed Google Scholar. Correspondence to Abbie E Smith-Ryan. ETT conceived of the review topic and drafted the manuscript.

AES conceived, drafted and revised the manuscript. LEN helped to draft and revise the manuscript. All authors read and approved the final manuscript. Open Access This article is published under license to BioMed Central Ltd.

Reprints and permissions. Trexler, E. Metabolic adaptation to weight loss: implications for the athlete. It is important to ensure good hydration prior to an event. Consuming approximately ml of fluid in the 2 to 4 hours prior to an event may be a good general strategy to take.

Some people may experience a negative response to eating close to exercise. A meal high in fat, protein or fibre is likely to increase the risk of digestive discomfort. It is recommended that meals just before exercise should be high in carbohydrates as they do not cause gastrointestinal upset.

Liquid meal supplements may also be appropriate, particularly for athletes who suffer from pre-event nerves. For athletes involved in events lasting less than 60 minutes in duration, a mouth rinse with a carbohydrate beverage may be sufficient to help improve performance.

Benefits of this strategy appear to relate to effects on the brain and central nervous system. During exercise lasting more than 60 minutes, an intake of carbohydrate is required to top up blood glucose levels and delay fatigue.

Current recommendations suggest 30 to 60 g of carbohydrate is sufficient, and can be in the form of lollies, sports gels, sports drinks, low-fat muesli and sports bars or sandwiches with white bread. It is important to start your intake early in exercise and to consume regular amounts throughout the exercise period.

It is also important to consume regular fluid during prolonged exercise to avoid dehydration. Sports drinks, diluted fruit juice and water are suitable choices.

For people exercising for more than 4 hours, up to 90 grams of carbohydrate per hour is recommended. Carbohydrate foods and fluids should be consumed after exercise, particularly in the first one to 2 hours after exercise.

While consuming sufficient total carbohydrate post-exercise is important, the type of carbohydrate source might also be important, particularly if a second training session or event will occur less than 8 hours later. In these situations, athletes should choose carbohydrate sources with a high GI for example white bread, white rice, white potatoes in the first half hour or so after exercise.

This should be continued until the normal meal pattern resumes. Since most athletes develop a fluid deficit during exercise, replenishment of fluids post-exercise is also a very important consideration for optimal recovery.

It is recommended that athletes consume 1. Protein is an important part of a training diet and plays a key role in post-exercise recovery and repair. Protein needs are generally met and often exceeded by most athletes who consume sufficient energy in their diet.

The amount of protein recommended for sporting people is only slightly higher than that recommended for the general public. For athletes interested in increasing lean mass or muscle protein synthesis, consumption of a high-quality protein source such as whey protein or milk containing around 20 to 25 g protein in close proximity to exercise for example, within the period immediately to 2 hours after exercise may be beneficial.

As a general approach to achieving optimal protein intakes, it is suggested to space out protein intake fairly evenly over the course of a day, for instance around 25 to 30 g protein every 3 to 5 hours, including as part of regular meals.

There is currently a lack of evidence to show that protein supplements directly improve athletic performance. Therefore, for most athletes, additional protein supplements are unlikely to improve sport performance.

A well-planned diet will meet your vitamin and mineral needs. Supplements will only be of any benefit if your diet is inadequate or you have a diagnosed deficiency, such as an iron or calcium deficiency.

There is no evidence that extra doses of vitamins improve sporting performance. Nutritional supplements can be found in pill, tablet, capsule, powder or liquid form, and cover a broad range of products including:.

Before using supplements, you should consider what else you can do to improve your sporting performance — diet, training and lifestyle changes are all more proven and cost effective ways to improve your performance.

Relatively few supplements that claim performance benefits are supported by sound scientific evidence. Use of vitamin and mineral supplements is also potentially dangerous. Supplements should not be taken without the advice of a qualified health professional.

The ethical use of sports supplements is a personal choice by athletes, and it remains controversial.

However, the particular timing of ingestion of carbohydrate foods with different GIs around exercise might be important. There is a suggestion that low GI foods may be useful before exercise to provide a more sustained energy release, although evidence is not convincing in terms of any resulting performance benefit.

Moderate to high GI foods and fluids may be the most beneficial during exercise and in the early recovery period. However, it is important to remember the type and timing of food eaten should be tailored to personal preferences and to maximise the performance of the particular sport in which the person is involved.

A high-carbohydrate meal 3 to 4 hours before exercise is thought to have a positive effect on performance. A small snack one to 2 hours before exercise may also benefit performance. It is important to ensure good hydration prior to an event.

Consuming approximately ml of fluid in the 2 to 4 hours prior to an event may be a good general strategy to take. Some people may experience a negative response to eating close to exercise.

A meal high in fat, protein or fibre is likely to increase the risk of digestive discomfort. It is recommended that meals just before exercise should be high in carbohydrates as they do not cause gastrointestinal upset. Liquid meal supplements may also be appropriate, particularly for athletes who suffer from pre-event nerves.

For athletes involved in events lasting less than 60 minutes in duration, a mouth rinse with a carbohydrate beverage may be sufficient to help improve performance.

Benefits of this strategy appear to relate to effects on the brain and central nervous system. During exercise lasting more than 60 minutes, an intake of carbohydrate is required to top up blood glucose levels and delay fatigue.

Current recommendations suggest 30 to 60 g of carbohydrate is sufficient, and can be in the form of lollies, sports gels, sports drinks, low-fat muesli and sports bars or sandwiches with white bread.

It is important to start your intake early in exercise and to consume regular amounts throughout the exercise period. It is also important to consume regular fluid during prolonged exercise to avoid dehydration.

Sports drinks, diluted fruit juice and water are suitable choices. For people exercising for more than 4 hours, up to 90 grams of carbohydrate per hour is recommended.

Carbohydrate foods and fluids should be consumed after exercise, particularly in the first one to 2 hours after exercise. While consuming sufficient total carbohydrate post-exercise is important, the type of carbohydrate source might also be important, particularly if a second training session or event will occur less than 8 hours later.

In these situations, athletes should choose carbohydrate sources with a high GI for example white bread, white rice, white potatoes in the first half hour or so after exercise.

This should be continued until the normal meal pattern resumes. Since most athletes develop a fluid deficit during exercise, replenishment of fluids post-exercise is also a very important consideration for optimal recovery. It is recommended that athletes consume 1.

Protein is an important part of a training diet and plays a key role in post-exercise recovery and repair. Protein needs are generally met and often exceeded by most athletes who consume sufficient energy in their diet. The amount of protein recommended for sporting people is only slightly higher than that recommended for the general public.

For athletes interested in increasing lean mass or muscle protein synthesis, consumption of a high-quality protein source such as whey protein or milk containing around 20 to 25 g protein in close proximity to exercise for example, within the period immediately to 2 hours after exercise may be beneficial.

As a general approach to achieving optimal protein intakes, it is suggested to space out protein intake fairly evenly over the course of a day, for instance around 25 to 30 g protein every 3 to 5 hours, including as part of regular meals. There is currently a lack of evidence to show that protein supplements directly improve athletic performance.

Therefore, for most athletes, additional protein supplements are unlikely to improve sport performance. A well-planned diet will meet your vitamin and mineral needs. Supplements will only be of any benefit if your diet is inadequate or you have a diagnosed deficiency, such as an iron or calcium deficiency.

There is no evidence that extra doses of vitamins improve sporting performance. Nutritional supplements can be found in pill, tablet, capsule, powder or liquid form, and cover a broad range of products including:.

Before using supplements, you should consider what else you can do to improve your sporting performance — diet, training and lifestyle changes are all more proven and cost effective ways to improve your performance.

Relatively few supplements that claim performance benefits are supported by sound scientific evidence. Use of vitamin and mineral supplements is also potentially dangerous. Supplements should not be taken without the advice of a qualified health professional.

The ethical use of sports supplements is a personal choice by athletes, and it remains controversial. If taking supplements, you are also at risk of committing an anti-doping rule violation no matter what level of sport you play.

Dehydration can impair athletic performance and, in extreme cases, may lead to collapse and even death. Drinking plenty of fluids before, during and after exercise is very important. Fluid intake is particularly important for events lasting more than 60 minutes, of high intensity or in warm conditions.

Water is a suitable drink, but sports drinks may be required, especially in endurance events or warm climates. Sports drinks contain some sodium, which helps absorption. While insufficient hydration is a problem for many athletes, excess hydration may also be potentially dangerous.

In rare cases, athletes might consume excessive amounts of fluids that dilute the blood too much, causing a low blood concentration of sodium. This condition is called hyponatraemia, which can potentially lead to seizures, collapse, coma or even death if not treated appropriately.

Consuming fluids at a level of to ml per hour of exercise might be a suitable starting point to avoid dehydration and hyponatraemia, although intake should ideally be customised to individual athletes, considering variable factors such as climate, sweat rates and tolerance.

This page has been produced in consultation with and approved by:. Content on this website is provided for information purposes only. Information about a therapy, service, product or treatment does not in any way endorse or support such therapy, service, product or treatment and is not intended to replace advice from your doctor or other registered health professional.

Similar to leptin, high levels of insulin convey a message of energy availability and are associated with an anorexigenic effect.

Conversely, the orexigenic hormone ghrelin functions to stimulate appetite and food intake, and has been shown to increase with fasting, and decrease after feeding [ 24 ]. Testosterone, known primarily for its role in increasing muscle protein synthesis and muscle mass [ 22 ], may also play a role in regulating adiposity [ 25 ].

Changes in fat mass have been inversely correlated with testosterone levels, and it has been suggested that testosterone may repress adipogenesis [ 25 ]. More research is needed to delineate the exact mechanism s by which testosterone affects adiposity.

Cortisol, a glucocorticoid that influences macronutrient metabolism, has been shown to induce muscle protein breakdown [ 22 ], and increased plasma cortisol within the physiologic range has increased proteolysis in healthy subjects [ 26 ].

Evidence also suggests that glucocorticoids may inhibit the action of leptin [ 27 ]. Results from a number of studies indicate a general endocrine response to hypocaloric diets that promotes increased hunger, reduces metabolic rate, and threatens the maintenance of lean mass.

Studies involving energy restriction, or very low adiposity, report decreases in leptin [ 1 , 10 , 28 ], insulin [ 1 , 2 ], testosterone [ 1 , 2 , 28 ], and thyroid hormones [ 1 , 29 ]. Subsequently, increases in ghrelin [ 1 , 10 ] and cortisol [ 1 , 30 , 31 ] have been reported with energy restriction.

Further, there is evidence to suggest that unfavorable changes in circulating hormone levels persist as subjects attempt to maintain a reduced body weight, even after the cessation of active weight loss [ 32 , 33 ].

Low energy intake and minimal body fat are perceived as indicators of energy unavailability, resulting in a homeostatic endocrine response aimed at conserving energy and promoting energy intake.

It should be noted that despite alterations in plasma levels of anabolic and catabolic hormones, losses of lean body mass LBM often fail to reach statistical significance in studies on bodybuilding preparation [ 1 , 2 ].

Although the lack of significance may relate to insufficient statistical power, these findings may indicate that unfavorable, hormone-mediated changes in LBM can potentially be attenuated by sound training and nutritional practices.

Previous research has indicated that structured resistance training [ 34 ] and sufficient protein intake [ 35 — 37 ], both commonly employed in bodybuilding contest preparation, preserve LBM during energy restriction. Further, Maestu et al. speculate that losses in LBM are dependent on the magnitude of weight loss and degree of adiposity, as the subjects who lost the greatest amount of weight and achieved the lowest final body fat percentage in the study saw the greatest losses of LBM [ 2 ].

The hormonal environment created by low adiposity and energy restriction appears to promote weight regain and threaten lean mass retention, but more research is needed to determine the chronic impact of these observed alterations in circulating anabolic and catabolic hormones.

The largest component, resting energy expenditure REE , refers to the basal metabolic rate BMR [ 8 ]. The other component, known as non-resting energy expenditure NREE , can be further divided into exercise activity thermogenesis EAT , non-exercise activity thermogenesis NEAT , and the thermic effect of food TEF [ 8 ].

Components of total daily energy expenditure TDEE. Adapted from Maclean et al. Metabolic rate is dynamic in nature, and previous literature has shown that energy restriction and weight loss affect numerous components of energy expenditure.

In weight loss, TDEE has been consistently shown to decrease [ 38 , 39 ]. Weight loss results in a loss of metabolically active tissue, and therefore decreases BMR [ 38 , 39 ]. Interestingly, the decline in TDEE often exceeds the magnitude predicted by the loss of body mass.

Previous literature refers to this excessive drop in TDEE as adaptive thermogenesis, and suggests that it functions to promote the restoration of baseline body weight [ 13 — 15 ]. Adaptive thermogenesis may help to partially explain the increasing difficulty experienced when weight loss plateaus despite low caloric intake, and the common propensity to regain weight after weight loss.

Exercise activity thermogenesis also drops in response to weight loss [ 40 — 42 ]. In activity that involves locomotion, it is clear that reduced body mass will reduce the energy needed to complete a given amount of activity. It has been speculated that this increase in skeletal muscle efficiency may be related to the persistent hypothyroidism and hypoleptinemia that accompany weight loss, resulting in a lower respiratory quotient and greater reliance on lipid metabolism [ 43 ].

The TEF encompasses the energy expended in the process of ingesting, absorbing, metabolizing, and storing nutrients from food [ 8 ]. While the relative magnitude of TEF does not appear to change with energy restriction [ 46 ], such dietary restriction involves the consumption of fewer total calories, and therefore decreases the absolute magnitude of TEF [ 41 , 46 ].

There is evidence to suggest that spontaneous physical activity, a component of NEAT, is decreased in energy restricted subjects, and may remain suppressed for some time after subjects return to ad libitum feeding [ 29 ]. Persistent suppression of NEAT may contribute to weight regain in the post-diet period.

In the context of weight loss or maintaining a reduced body weight, this process is complicated by the dynamic nature of energy expenditure.

In response to weight loss, reductions in TDEE, BMR, EAT, NEAT, and TEF are observed. Due to adaptive thermogenesis, TDEE is lowered to an extent that exceeds the magnitude predicted by losses in body mass.

Further, research indicates that adaptive thermogenesis and decreased energy expenditure persist after the active weight loss period, even in subjects who have maintained a reduced body weight for over a year [ 14 , 48 ].

These changes serve to minimize the energy deficit, attenuate further loss of body mass, and promote weight regain in weight-reduced subjects. A series of chemical reactions must take place to derive ATP from stored and ingested energy substrates.

In aerobic metabolism, this process involves the movement of protons across the inner mitochondrial membrane. When protons are transported by ATP synthase, ATP is produced. Protons may also leak across the inner membrane by way of uncoupling proteins UCPs [ 49 ].

In the condition of calorie restriction, proton leak is reduced [ 16 — 19 ]. Uncoupling protein-1 and UCP-3, the primary UCPs of brown adipose tissue BAT and skeletal muscle [ 53 ], are of particular interest due to their potentially significant roles in energy expenditure and uncoupled thermogenesis.

Decreased UCP-3 expression could potentially play a role in decreasing energy expenditure, and UCP-3 expression has been negatively correlated with body mass index and positively correlated with metabolic rate during sleep [ 57 ].

Despite these correlations, more research is needed to determine the function and physiological relevance of UCP-3 [ 58 ], as contradictory findings regarding UCP-3 and weight loss have been reported [ 18 ]. Uncoupling Protein-1 appears to play a pivotal role in the uncoupled thermogenic activity of BAT [ 59 ].

Energy restriction has been shown to decrease BAT activation [ 60 ] and UCP-1 expression [ 61 ], indicating an increase in metabolic efficiency. Along with UCP-1 expression, thyroid hormone and leptin affect the magnitude of uncoupled respiration in BAT. Thyroid hormone TH and leptin are associated with increased BAT activation, whereas glucocorticoids oppose the BAT-activating function of leptin [ 59 ].

Evidence indicates that TH plays a prominent role in modulating the magnitude of proton leak [ 53 ], with low TH levels associated with decreased proton leak [ 62 ].

The endocrine response to energy restriction, including increased cortisol and decreased TH and leptin [ 1 , 10 , 28 — 31 ], could potentially play a regulatory role in uncoupled respiration in BAT.

It is not clear if decreases in proton leak and UCP expression persist until weight reverts to baseline, but there is evidence to suggest a persistent adaptation [ 19 , 55 , 56 ], which mirrors the persistent downregulation of TH and leptin [ 32 , 33 ].

Changes observed in proton leak, UCP expression, and circulating hormones appear to influence metabolic efficiency and energy expenditure.

In the context of energy restriction, the observed changes are likely to make weight loss increasingly challenging and promote weight regain. It has been reported that females have more BAT than males [ 63 ], and that energy-restricted female rats see greater decreases in BAT mass and UCP-1 than males [ 64 ], indicating a potential sex-related difference in uncoupled respiration during weight loss.

While future research may improve our understanding of the magnitude and relative importance of mitochondrial adaptations to energy restriction, current evidence suggests that increased mitochondrial efficiency, and a decline in uncoupled respiration, might serve to decrease the energy deficit in hypocaloric conditions, making weight maintenance and further weight reduction more challenging.

Hypocaloric diets induce a number of adaptations that serve to prevent further weight loss and conserve energy. It is likely that the magnitude of these adaptations are proportional to the size of the energy deficit, so it is recommended to utilize the smallest possible deficit that yields appreciable weight loss.

This may decrease the rate of weight loss, but attenuate unfavorable adaptations that challenge successful reduction of fat mass. Large caloric deficits are also likely to induce greater losses of LBM [ 66 , 67 ] and compromise athletic performance and recovery [ 68 , 69 ], which are of critical importance to athletes.

Participation in a structured resistance training program [ 34 ] and sufficient protein intake [ 35 — 37 ] are also likely to attenuate losses in LBM. A refeed consists of a brief overfeeding period in which caloric intake is raised slightly above maintenance levels, and the increase in caloric intake is predominantly achieved by increasing carbohydrate consumption.

While studies have utilized refeeding protocols that last three days [ 71 , 72 ], physique athletes such as bodybuilders and figure competitors often incorporate hour refeeds, once or twice per week.

The proposed goal of periodic refeeding is to temporarily increase circulating leptin and stimulate the metabolic rate. There is evidence indicating that leptin is acutely responsive to short-term overfeeding [ 72 ], is highly correlated with carbohydrate intake [ 71 , 73 ], and that pharmacological administration of leptin reverses many unfavorable adaptations to energy restriction [ 33 ].

While interventions have shown acute increases in leptin from short-term carbohydrate overfeeding, the reported effect on metabolic rate has been modest [ 71 ].

Dirlewanger et al. More research is needed to determine if acute bouts of refeeding are an efficacious strategy for improving weight loss success during prolonged hypocaloric states.

A theoretical model of metabolic adaptation and potential strategies to attenuate adaptations is presented in Figure 2. A theoretical model of metabolic adaptation and potential strategies to attenuate adaptations.

Dotted lines represent inhibition. In the period shortly after cessation of a restrictive diet, body mass often reverts toward pre-diet values [ 29 , 74 , 75 ]. This body mass is preferentially gained as fat mass, in a phenomenon known as post-starvation obesity [ 29 ].

While many of the metabolic adaptations to weight loss persist, a dramatic increase in energy intake results in rapid accumulation of fat mass.

In such a situation, the individual may increase body fat beyond baseline levels, yet retain a metabolic rate that has yet to fully recover. There is evidence to suggest that adipocyte hyperplasia may occur early in the weight-regain process [ 76 ], and that repeated cycles of weight loss and regain by athletes in sports with weight classes are associated with long-term weight gain [ 77 ].

Therefore, athletes who aggressively diet for a competitive season and rapidly regain weight may find it more challenging to achieve optimal body composition in subsequent seasons.

Such a process involves slowly increasing caloric intake in a stepwise fashion. In theory, providing a small caloric surplus might help to restore circulating hormone levels and energy expenditure toward pre-diet values, while closely matching energy intake to the recovering metabolic rate in an effort to reduce fat accretion.

Ideally, such a process would eventually restore circulating hormones and metabolic rate to baseline levels while avoiding rapid fat gain. While anecdotal reports of successful reverse dieting have led to an increase in its popularity, research is needed to evaluate its efficacy. Accordingly, the current article is limited by the need to apply this data to an athletic population.

If the adaptations described in obese populations serve to conserve energy and attenuate weight loss as a survival mechanism, one might speculate that the adaptations may be further augmented in a leaner, more highly active population.

Another limitation is the lack of research on the efficacy of periodic refeeding or reverse dieting in prolonged weight reduction, or in the maintenance of a reduced bodyweight. Until such research is available, these anecdotal methods can only be evaluated from a mechanistic and theoretical viewpoint.

Weight loss is a common practice in a number of sports. Whether the goal is a higher strength-to-mass ratio, improved aesthetic presentation, or more efficient locomotion, optimizing body composition is advantageous to a wide variety of athletes.

As these athletes create an energy deficit and achieve lower body fat levels, their weight loss efforts will be counteracted by a number of metabolic adaptations that may persist throughout weight maintenance.

Changes in energy expenditure, mitochondrial efficiency, and circulating hormone concentrations work in concert to attenuate further weight loss and promote the restoration of baseline body mass.

Athletes must aim to minimize the magnitude of these adaptations, preserve LBM, and adequately fuel performance and recovery during weight reduction. To accomplish these goals, it is recommended to approach weight loss in a stepwise, incremental fashion, utilizing small energy deficits to ensure a slow rate of weight loss.

Participation in a structured resistance training program and adequate protein intake are also imperative. More research is needed to verify the efficacy of periodic refeeding and reverse dieting in supporting prolonged weight reduction and attenuating post-diet fat accretion.

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