However, there are some basic guidelines that will enable you to eliminate much of the guesswork, so you can more rapidly learn how to properly fuel your body during workouts and races.

Before you subscribe to and follow those suggestions, consider the words of Bill Misner, Ph. The human body has so many survival safeguards by which it regulates living one more minute, that when we try too hard to fulfill all its needs we interfere, doing more harm than good.

If I replace all the fuels I lose at the rate of calories per hour, I bloat, vomit, present diarrhea, and finish the event walking or at an aid station. If I replace all the fluids lost all at once, I end up in the emergency tent with an IV for dilutional hyponatremia.

Pretty bold words and warnings , indeed. If you follow our suggestions, we believe you will not only avoid performance-ruining and potentially health-threatening consequences, you will also have much more enjoyable experiences and achieve better performances in your workouts and races.

These suggestions have their roots in science and have been proven time and time again and again and again over the course of several years. You have nothing to lose, and a whole lot to gain, by testing them in your training.

Acute overhydration can cause hyponatremic low sodium induced coma and death. Cool weather exercise might require only a little over half of that. Big athlete, very hot and humid conditions—maybe up to ml.

Sure, you can sweat more than that, but you cannot physiologically replace it ounce-for-ounce. Regular fluid intake close to or over a liter hourly really increases the potential for serious performance and health problems, so keep that in mind before you indiscriminately gulp down excessive amounts of fluid.

Sound like a good strategy to you? Far too many athletes think they need to match calories out with equal amounts of calories in. Guess what—simple sugars glucose, sucrose, fructose, and dextrose are garbage. They have no place in your body. Simple sugars give you energy peaks and crashes, and they also have a severe limitation on absorption.

Complex carbohydrates, however, absorb at about three times the rate as simple sugars. Plus you get smooth, steady, reliable energy—no peaks and valleys. Yes, complex carbohydrates do contain, as part of their naturally occurring structure, a small percentage of 1- or 2-chain sugars.

You have two choices:. Do not use it before or during because the added glutamine quickly degrades to produce ammonia. Soy or rice gives you the protein you need with minimal extra ammonia production. After exercise, when ammonia production is not an issue, glutamine-enhanced whey protein is great for immune system boosting, muscle tissue rebuilding, and enhanced glycogen synthesis.

Solid food is harder to digest than liquid, and it requires more time, water, and electrolytes. Relying too heavily on solid foods can leave you feeling lethargic, bloated, and nauseated.

Liquid fuels digest and absorb readily, so you avoid those unwanted maladies. Most of all, avoid all junk foods, which contain lots of saturated fats and refined sugars, at all times.

Instead, you get cramps, spasms, muscle revolt, irregular and rapid heartbeat, and major bonk. Salt is just one of several electrolytes you need to replenish during exercise. Calcium, magnesium, and potassium also play key roles in fulfilling electrolyte requirements.

How much salt is enough? You need to experiment and find your own range for any given weather condition and duration of exercise. These all must be tested and refined in training.

Because all Hammer fuels are specific and formulated to easily combine with one another, you have all the flexibility you need to ensure that you can tailor a fueling program for any length of race, regardless of conditions. Caloric intakes that worked during training may not be appropriate during a race; you may need to consume slightly less in a race than you did during training.

Increased anxiety, increased pace, and increased potential for dehydration all contribute to the possibility of a less-than-optimally functioning digestive system. In addition, at the increased pace during a race, more blood is diverted from digestion and directed toward maintaining muscle performance.

You may need to alter that game plan which may mean a slightly lower hourly intake of calories to accommodate the possibility of a less-than-optimal digestive system. Equally important as your workout muscle exhaustion and nutrient depletion is what you do immediately following your workout muscle repair and nutrient replenishment.

An ideal and easy-to-use post-workout fuel is Recoverite, with its ratio of complex carbohydrates and protein. Bodyweight Drills. Advanced Training. AHP Exclusives. By Publication. By Muscle Group. By Topic. By Exercise. Submit Article. New Year's Sale. Athletic Performance - Training Services -.

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Nonetheless, a systematic review and meta-analysis of 21 investigations [ ] concluded the co-ingestion of carbohydrate and caffeine significantly improved endurance performance when compared to carbohydrate alone.

However, it should be noted that the magnitude of the performance benefit that caffeine provides is less when added to carbohydrate i. carbohydrate than when isolated caffeine ingestion is compared to placebo [ ].

Since the publication [ ], results remain inconclusive, as investigations related to sport-type performance measures [ 83 , , , , , , ], as well as endurance performance [ 84 , , ] continue to be published.

Overall, to date it appears caffeine alone, or in conjunction with carbohydrate is a superior choice for improving performance, when compared to carbohydrate supplementation alone. Few studies to date have investigated the effect of post-exercise caffeine consumption on glucose metabolism [ , ].

While the delivery of exogenous carbohydrate can increase muscle glycogen alone, Pedersen et al. In addition, it has been demonstrated that co-ingestion of caffeine with carbohydrate after exercise improved subsequent high-intensity interval-running capacity compared with ingestion of carbohydrate alone.

This effect may be due to a high rate of post-exercise muscle glycogen resynthesis [ ]. Practically, caffeine ingestion in close proximity to sleep, coupled with the necessity to speed glycogen resynthesis, should be taken into consideration, as caffeine before bed may cause sleep disturbances.

The genus of coffee is Coffea , with the two most common species Coffea arabica arabica coffee and Coffea canephora robusta coffee used for global coffee production.

While coffee is commonly ingested by exercising individuals as part of their habitual diet, coffee is also commonly consumed pre-exercise to improve energy levels, mood, and exercise performance [ 11 , 40 ].

Indeed, a recent review on coffee and endurance performance, reported that that coffee providing between 3 and 8. Specifically, Higgins et al. Since the release of the Higgins et al. review, three additional studies have been published, examining the effects of coffee on exercise performance.

Specifically, Niemen et al. Fifty-km cycling time performance and power did not differ between trials. Regarding resistance exercise performance, only two studies [ 55 , 56 ] have been conducted to date. One study [ 56 ] reported that coffee and caffeine anhydrous did not improve strength outcomes more than placebo supplementation.

On the other hand, Richardson et al. The results between studies differ likely because it is challenging to standardize the dose of caffeine in coffee as differences in coffee type and brewing method may alter caffeine content [ ].

Even though coffee may enhance performance, due to the difficulty of standardizing caffeine content most sport dietitians and nutritionists use anhydrous caffeine with their athletes due to the difficulty of standardizing caffeine content. Consumption of energy drinks has become more common in the last decade, and several studies have examined the effectiveness of energy drinks as ergogenic aids Table 8.

Souza and colleagues [ ] completed a systematic review and meta-analysis of published studies that examined energy drink intake and physical performance. Studies including endurance exercise, muscular strength and endurance, sprinting and jumping, as well as sport-type activities were reviewed.

It has been suggested that the additional taurine to caffeine containing energy drinks or pre-workout supplements, as well as the addition of other ergogenic supplements such as beta-alanine, B-vitamins, and citrulline, may potentiate the effectiveness of caffeine containing beverages on athletic performance endeavors [ ].

However, other suggest that the ergogenic benefits of caffeine containing energy drinks is likely attributed to the caffeine content of the beverage [ ].

For a thorough review of energy drinks, consider Campbell et al. Table 8 provides a review of research related to energy drinks and pre-workout supplements.

Caffeine in its many forms is a ubiquitous substance frequently used in military, athletic and fitness populations which acutely enhance many aspects of exercise performance in most, but not all studies.

Supplementation with caffeine has been shown to acutely enhance many aspects of exercise, including prolonged aerobic-type activities and brief duration, high-intensity exercise.

The optimal timing of caffeine ingestion likely depends on the source of caffeine. Studies that present individual participant data commonly report substantial variation in caffeine ingestion responses.

Inter-individual differences may be associated with habitual caffeine intake, genetic variations, and supplementation protocols in a given study. Caffeine may be ergogenic for cognitive function, including attention and vigilance. Caffeine at the recommended doses does not appear significantly influence hydration, and the use of caffeine in conjunction with exercise in the heat and at altitude is also well supported.

Alternative sources of caffeine, such as caffeinated chewing gum, mouth rinses, and energy gels, have also been shown to improve performance. Energy drinks and pre-workouts containing caffeine have been demonstrated to enhance both anaerobic and aerobic performance.

Individuals should also be aware of the side-effects associated with caffeine ingestion, such as sleep disturbance and anxiety, which are often linearly dose-dependent.

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