As published in the Townsend Letter Dec 2013
Becoming leaner, faster, stronger, and able to perform better for longer, all while staying healthy, is the hope of every athlete from the weekend warrior to the elite professional. The lifestyle and nutrition of the athlete, especially at the professional level, are about fueling performance, recovering from stress, building skill quickly, and maintaining optimal body composition for the sport.
The ultimate goal, especially at the professional level, is to improve performance. Unfortunately, many athletes even at the high school level resort to banned or illegal substances in the hopes of gaining a competitive advantage. While many pharmaceuticals and nutraceuticals can provide an advantage, many of them also have dangerous side effects.
The purpose of this three-part series is to provide the athlete and associated team of coaches, trainers, health-care providers, and so on, with tools for improving athletic performance in a safe and legitimate way. Part 1 focuses on lifestyle and nutrition (the foundation), while parts 2 and 3 discuss the evidence regarding the ergogenic effects of nutraceuticals and the possible issues (side effects and legitimacy) involved with using them.
Definition of an Ergogenic Aid
Many people define an ergogenic substance in simplistic terms, such as a drug or supplement that improves athletic performance. According to the International Society of Sports Nutrition (ISSN), the definition of an ergogenic aid “is any training technique, mechanical device, nutritional practice, pharmacological method, or psychological technique that can improve exercise performance capacity and/or enhance training adaptations.”1 By this definition, anything that allows an athlete to stay consistent and efficient with exercise, training, and performance is an ergogenic aid. If it helps with recovery, enhanced performance, and injury avoidance, then it is considered ergogenic. This definition indicates a lot of potential for improving athletic performance through lifestyle, training techniques (physical and mental), recovery methods, nutrition, and supplementation. The ergogenic arsenal available to the athlete is vast, but rarely used to its greatest extent.
The Foundation for Improving Athletic Performance
So what exactly is the foundation for improving athletic performance? It is about improving athletes’ lifestyles to meet the demands of their particular sports. Common sense dictates that a poor lifestyle (lack of sleep, poor nutrition, chronic stress, etc.) will adversely affect performance not only on the field or court, but in all areas of life. An in-depth assessment of lifestyle habits is paramount for the athlete.
Sleep and Performance
Most athletes will need more sleep, rest, and recovery than the average weekend warrior due to the grueling training and competition schedule. There is accumulating evidence to suggest that quality and adequate duration of sleep will assist athletes to perform at their highest potential.2,3,5 Adequate sleep will help with recovery, stress, and cognitive ability. Other considerations regarding sleep quality include paying attention to travel schedules, jet lag from traveling across multiple time zones, and other obligations (e.g., work, family, academic).4
Assuming that sleep habit issues and deficiencies have been addressed, the next level to assess is the nutritional status in terms of hydration, macronutrient ratios, meal timing, and overall caloric intake with regard to training and performance schedule.
Water is easily the most important ergogenic aid. Training and competition can result in significant losses of water through sweat, and this can be further exacerbated depending on the temperature, humidity, and exercise intensity. Working to maintain adequate hydration during exercise is one of the most useful endeavors for improving performance. The following table is summary of the ISSN stand on athletic performance and hydration.1,44-48
Dietary Needs and Performance
Second only to adequate hydration, a caloric-sufficient diet is the most important ergogenic aid. A balanced diet plan that meets the energy demands of the athlete’s training and competition schedule is key to promoting ergogenesis.6-9 It is well known that an energy-deficient diet can be caused by poor planning and choices, and even overtraining. Furthermore, a caloric-deficient diet can lead to a loss of lean mass, motivation, and training intensity.
The average person who exercises 3 to 5 times week 30 min/day can usually meet caloric needs following a well-balanced diet of 1800 to 2400 kcal/day. On the other hand, some athletes demand extremely high caloric loads, more than 6000 to 12,000 kcal/day.15 Elite athletes, such as professional cyclists or marathoners, can burn as much as 12,000 calories/day, necessitating a large compensatory calorie intake. Caloric needs this great can be extremely difficult to obtain through food resources.10 This makes supplementation a necessary consideration for all athletes undergoing high-volume training.
Some athletes are often under the constraints of tight schedules of competition and travel requirements that can interrupt scheduled meals. To account for these issues, athletes should work to assure that muscle is not lost and appropriate weight is maintained. This means eating calorie-dense meals and snacks that are convenient for an athlete’s lifestyle. While real foods should be emphasized, meal-replacement bars and shakes should also be used. Liquid calories are a quick and convenient way to assure caloric sufficiency.
It is recommend that athletes eat between 4 and 6 meals/day and strive to eat in consistently timed intervals.1 Meal and snack timing around training and competition is also an important consideration for energy and recovery. Without caloric balance, most supportive training aids will not provide an advantage.
Performance Nutrition and Fat Loss
Excelling in sport has much to do with achieving and maintaining an ideal body composition. Athletes seek to optimize the correct ratio of muscle to fat that enhances performance. More times than not, simply participating in the sport elicits the ideal body composition. But when it does not, an athlete may at times seek to increase muscle mass or decrease fat weight.
The “glycogen paradigm” is a way of thinking about sports performance that seeks to maximize muscle sugar storage. This, it is believed, is the best way to increase training intensity, accelerate recovery, and improve performance. This glycogen dogma has resulted in confusion for athletes and fitness enthusiasts regarding optimal exercise for improving body composition. It has been known for some time that maximizing glycogen storage increases the performance of endurance athletes. A 1993 study by Wagenmakers et al. showed this conclusively. However, this study also showed a direct negative association between glycogen storage and fat burning.16 Other studies have shown that exercise done in a glycogen-depleted state appear to have benefits for increasing fat loss.12-14
When fat loss is the key aim of an athlete, it may be important to tweak the glycogen-centered philosophy of maximizing performance to an approach that instead focuses on fat loss. Understanding the positive association of glycogen with performance â€“ and the negative association with fat loss â€“ can make a huge difference for the athlete.
In addition to caloric considerations, balancing macronutrient ratios is also important for athletes. Unlike the macronutrient needs of recreationally active individuals (typically 45%â€“55% carbohydrates, 10%â€“15% protein, and 25%â€“35% fat), the needs of athletes usually greatly exceed these numbers.
Depending on the sport, carbohydrate (CHO) needs can increase significantly in order to replenish and maximize liver and muscle glycogen storage.1,15-17 Because the levels of CHO for some athletes, especially endurance athletes, can be hard to consume, fruit juices, energy bars, and so on, should be utilized.
Research related to CHOs in athletes shows that there might be what we call a “carbohydrate tipping point.”1 This is the level of CHO beyond which there ceases to be a performance advantage. Another way to think about this tipping point is the amount of CHO needed for optimal performance without causing fat storage. Research suggests that the body can burn 1 to 1.1 g of CHO/min, amounting to roughly 60 g of CHO/hr.18 Studies show that approximately 30 to 70 g of CHO/hr for a 50 kg (110 lbs) to 100 kg (220 lbs) person, respectively, would optimize CHO utilization.19-21
Understanding that some CHOs are metabolized and oxidized differently is also important. Sugars composed of glucose (maltose, maltodextrin, and sucrose) are burned at a higher rate than nonglucose sugars such as fructose and galactose.22,23 A combination of these sugars appears to be optimal. Evaluating CHO sources on the relative ratios of these sugars may be wise. A glucose to fructose ratio of close to 1:1 seems best, which is the ratio of sucrose.
Protein (PRO) makes up about half the human body’s dry weight and is the second most abundant nutrient in the body after water. Research on protein intake has shown that athletes engaged in intense training and performance require 2Ã— the RDI (reference daily intake) or more.24-28 It is now recommended that athletes involved in very high-volume training consume between 0.7 to 0.9 g of PRO/lb of body weight per day. This amounts to between 115 and 150 g of PRO/day for a 165-pound athlete. This would be the equivalent of about 5 servings of chicken, fish, or other lean protein daily. PRO considerations are especially important for endurance athletes, who are more susceptible to PRO malnutrition due to the catabolic hormonal environment created by their sport.
The amino acid content of PRO sources can vary and has direct bearing on the quality. Different types of PRO can be described as fast or slow. Slow PROs are digested more evenly and take longer to process. Fast PROs are digested more rapidly and allow amino acids to be quickly available to the body. The typical fast and slow PRO sources would be whey and casein, respectively. Slow PROs may be better meal options, while fast PROs are better options to aid performance and recovery. The best sources of supplemental protein are low fat and have a high biological value; this includes egg and milk-based proteins (whey and casein).
The International Society of Sports Nutrition published its position stand on protein intake in 2010 highlighting the following points1:
1. Highly active individuals should consume between 1.4 to 2 g of protein per kg of body weight.
2. Concerns that protein intake within this range is unhealthful are unfounded.
3. Supplemental protein is a safe and viable method of protein intake. especially when whole-food proteins are not convenient.
4. Timing protein intake to occur before and after exercise will enhance recovery and development of muscle mass.
5. Protein supplements such as branched chain amino acids and whey have been shown to be beneficial by increasing the rate of protein synthesis, decreasing protein breakdown, and increasing recovery from exercise.
6. Exercising individuals require more protein than their sedentary counterparts.
The types of fat consumed should also be considered. The polyunsaturated fatty acid ratio of w-6:w-3 can influence the immune system and inflammatory responses. Medium-chain saturated fats found in coconut are oxidized faster than long-chain saturated fats, which may provide a quicker energy source and possibly inhibit fat storage.
Like CHOs and PRO, fat intake should also be greater for the athlete. High-volume athletic training has been shown to lower testosterone concentrations, and decreasing fat intake can exacerbate this effect.29-32 Most research suggests that athletes should keep their dietary fat intake at about 30% of total calories. However, ultraendurance athletes may go much higher than this, as much as 50% of total calories at times.33 As mentioned previously, weight loss is occasionally a concern for athletes. In these cases, a lower-fat diet may be advisable.
Given these considerations of fat, it is wise for some athletes to consume higher amounts of certain fats with a special attention towards balancing the w-6:w-3.
Performance, Recovery, and Nutrient Timing
Athletes and those working with them can benefit greatly from understanding how to time meals for performance and recovery. When it comes to performance nutrition, it is useful to think about first maximizing liver and muscle glycogen stores and maintaining appropriate nutrition to fuel exercise. CHO has been shown to take about 4 to 6 hours to be eaten, absorbed, and stored in the liver and muscle as glycogen.7 Recommendations regarding CHO loading for training and events should take this into account for endurance athletes. Morning training sessions or events will benefit from nighttime loading strategies, while afternoon events and training sessions will benefit from morning loading strategies.
To improve performance of high-intensity activity, a CHO (40â€“60 g) and PRO (5â€“15 g) snack approximately 45 min before activity may give an advantage.34,35 This snack also serves to spare muscle tissue by decreasing the need for the body to cannibalize it.28
While exercise sessions of less than an hour usually do not require any special nutritional or hydration strategies, sessions lasting longer do. Strategies that manage preâ€‘, post-, and intraworkout strategies can dramatically aid performance and recovery. This is when electrolyte solutions and sports drinks consumed before and during exercise have an important role. These beverages can help prevent low blood sugar, optimize hydration, replace loss of minerals, and reduce the immune suppression that occurs after intense long-duration exercise.36-41 A CHO beverage of 6% to 8% with an equal mixture of glucose and fructose taken every 20 min during exercise can be helpful.
Postexercise, there is a unique opportunity to fuel the body for recovery. Nutritional strategies should be instituted within the first 30 to 60 min after the cessation of exercise. A mixed CHO/PRO beverage containing close to a 3:1 ratio of CHO to PRO after exercise appears to provide greater recovery benefits than lesser amounts of CHO.6,7,42,43 Upon completion of this postworkout “snack,” a more CHO-heavy postworkout meal should be eaten within 90 min. The addition of a small amount of fat may also be helpful in stabilizing blood glucose levels.
Most athletes will taper their training by 1/3 to 1/2 on days 2 to 5 leading up to their event. During this time, it may be beneficial to consume from 200 to 300 extra g of CHO daily. This technique has been shown to maximize glycogen storage pre-event and improve performance.6,7,42,43
The following points are the ISSN position stand on nutrient timing1:
- Prolonged exercise (>60â€“90 min) of moderate- to high-intensity exercise will deplete the internal stores of energy, and prudent timing of nutrient delivery can help offset these changes.
- During intense exercise, regular consumption (10â€“15 fl oz.) of a carbohydrate/electrolyte solution delivering 6% to 8% CHO (6â€“8 g CHO/100 ml fluid) should be consumed every 15 to 20 min to sustain blood glucose levels.
- Glucose, fructose, sucrose, and other high-glycemic CHO sources are easily digested, but fructose consumption should be minimized as it is absorbed at a slower rate and increases the likelihood of GI problems.
- The addition of PRO (0.15â€“0.25 g PRO/kg/day) to CHO, especially postexercise, is well tolerated and may promote greater restoration of muscle glycogen when carbohydrate intakes are suboptimal.
- Ingestion of 10 to 20 g of essential amino acids and 30 to 40 g of high-glycemic CHO within 3 hrs after an exercise bout and immediately before exercise has been shown to significantly stimulate muscle PRO synthesis.
- Daily postexercise ingestion of a CHO + PRO supplement promotes greater increases in strength and improvements in lean tissue and body fat percentage during regular resistance training.
- Milk PRO sources (e.g., whey and casein) exhibit different kinetic digestion patterns and may subsequently differ in their support of training adaptations.
- Dietary focus should center on adequate availability and delivery of CHO and PRO. Including small amounts of fat does not appear to be harmful, and may help to control glycemic responses during exercise.
- Irrespective of timing, regular ingestion of snacks or meals providing both CHO and PRO (3:1 CHO: PRO ratio) helps to promote recovery and replenishment of muscle glycogen when lesser amounts of CHO are consumed.
The foundation of health for the average person is similar to the foundation for improving athletic performance in the athlete. If there is a deficiency in sleep, nutrition, or hydration, athletic performance will suffer. It is extremely important to address these issues before looking for the magic ergogenic pill, because lifestyle deficiencies will negate the potential other ergogenic aids. As stated above, sufficient sleep, caloric intake, and hydration can be ergogenic by themselves. The primary aids for enhancing athletic performance are as follows: sleep and caloric sufficiency, adequate hydration, adequate recovery, and appropriate timing of nutrients.
|Hydration and Athletic Performance
Performance can be significantly impaired when >2% body weight is lost through sweat. When a 70 kg athlete loses >1.4 kg of body weight during exercise (2%), performance is often significantly decreased. Further, weight loss >4% of body weight during exercise may lead to heat-related illness, and possibly death.The normal sweat rate of athletes ranges from 0.5â€“2.0 L/h depending on temperature, humidity, exercise intensity, and sweat response to exercise .To maintain fluid balance and prevent dehydration, athletes need to ingest 0.5â€“2 L/h of fluid in order to offset weight loss. This requires frequent ingestion of 6â€“8 oz of cold water or sports drink every 5â€“15 min. during exercise.Athletes should not depend on thirst to prompt them to drink because people do not typically get thirsty until they have lost a significant amount of fluid through sweat.Athletes should consider weighing themselves prior to and following exercise training to ensure that they maintain proper hydration. They should consume 3 cups of water for every lb. lost during exercise to adequately rehydrate themselves. Athletes should train themselves to tolerate drinking greater amounts of water during training and make sure that they consume more fluid in hotter/more humid environments.Preventing dehydration during exercise is one of the most effective ways to maintain exercise capacity.Inappropriate and excessive weight loss techniques (e.g., cutting weight in saunas, wearing rubber suits, severe dieting, vomiting, using diuretics) are extremely dangerous and should be prohibited. Making weight through dehydration techniques also causes one to compromise performance.
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