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This article explores the effects of nutrition and recovery strategies on athletic performance, including the use of supplementation. It discusses the reasons why athletes turn to nutritional supplements, the importance of a well-balanced diet and training program, and the regulation of the supplement industry. The article also highlights the risks of doping with nutritional supplements and the role of vitamins and minerals in optimal performance.
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HSC PDHPE – CQ3 DP2 CQ3 – How can nutrition and recovery strategies affect performance?
2. supplementation • In their search to run faster, leap higher and become bigger, athletes use a number of ergogenic aids. The term ‘ergogenic’ comes from the Latin words for ‘energy-producing’. An ergogenic aid is a technique that is designed to improve or increase work output and might be illegal (for example, performance-enhancing drugs) or legal (for example, training methods or the use of a nutritional supplement).
supplementation • Athletes turn to nutritional supplements for a number of reasons. These include: • a belief that supplements might enhance their performance • a belief that their training needs are too high to be met by normal food intake • a belief that they eat poorly or have an unhealthy lifestyle • a belief in the claims of advertising. • Although one or more of these factors might be applicable to some athletes, most athletes should be able to meet their nutritional requirements through specialised training diets.
supplementation • Nutritional supplementation should be considered the tip of the pyramid. Nutritional supplements may not be as effective as they could be if the athlete does not have a meal plan that meets the athlete’s energy, macronutrient and micronutrient requirements, combined with a well designed training program. In fact, in some situations, supplementing an athlete’s diet with extra nutrients may reduce the athlete’s adaptation to training.
supplementation • In Australia the nutritional supplement industry is regulated by the Therapeutic Goods Administration (TGA). The TGA regulates the contents of supplements and the claims made by supplement companies. Its role is to ensure companies are not making false claims about their products and are not including ingredients that are illegal in Australia. Despite this regulation, there are still many products on the market with capabilities that are overemphasised. It is the responsibility of each athlete and coach to use all information available to determine the benefits and side effects of a nutritional supplement and decide whether conditions exist in which supplements might be useful for the athlete.
Risk of doping with nutritional supplements • With the greater focus on drug testing in the current sporting world, supplementation has been identified as a potential source for ‘inadvertent doping’. There have been numerous cases where athletes have tested positive to substances banned under the World Anti-Doping Agency (WADA) code and later found that the source of the substances were nutritional supplements. An international study in 2004 found that out of 634 supplements tested, 15% of the supplements were found to be positive for doping substances.
Risk of doping with nutritional supplements • These products containing doping substances were not isolated to one country: the supplements came from the United States, the United Kingdom, the Netherlands, Italy and Germany. No Australian products were included in this study. This raises an important issue for athletes who are taking nutritional supplements as, under WADA rules, being unaware that the supplement contained a doping substance is not a valid defence. Some athletes regularly take nutritional supplements without any concern for these issues. Any athlete taking nutritional supplements must give sufficient consideration to the risks associated with taking such substances from unknown sources.
vitamins/minerals • Vitamins and minerals are required for health and optimal performance. Deficiencies can lead to symptoms of fatigue, infections, illnesses and slower recovery time from injury. Deficiencies can occur in a small population of athletes; these are usually closely linked to the inability of those athletes to meet their energy requirements.
vitamins/minerals • It is a common attitude of athletes that it is cheaper and easier to take a supplement than it is to fix the underlying reason for the deficiency. Even though true vitamin and mineral deficiencies rarely occur in athletic populations a majority of athletes take vitamin and mineral supplements. Athletes and supplement company advertising often justify this practice through the assumption that athletes need far higher doses of these vitamins and minerals than do the average population.
vitamins/minerals • Another common reason for consumption of vitamin and mineral supplements is the belief that given the difference between winning and losing is so small, athletes may not want to risk not taking them. This provides them with a false sense of accomplishment; they may be satisfied that by taking these supplements their diet is nutritionally adequate when, in fact, it may still be inadequate.
Vitamins • Vitamins are organic compounds that are required in small quantities for normal growth, development and metabolism. They often act as co-enzymes to assist the enzymes that catalyse the breakdown of carbohydrate, proteins and fats.
Vitamins • Vitamins can be divided into two distinct groups: fat-soluble vitamins and water-soluble vitamins. • Fat-soluble vitamins are A, D, E and K. They are usually stored in the body’s adipose tissue and, as such, can build up to toxic levels if large amounts are taken over time. • Water-soluble vitamins are the B-group vitamins and vitamin C. These vitamins dissolve in water and are easily expelled by the body if intake is excessive. Therefore, athletes need to consume foods high in water-soluble vitamins more often than foods containing fat soluble vitamins.
Vitamins • Although the vitamin supplementation industry is massive, the average healthy adult can meet his or her RDI of all vitamins and minerals from a well-balanced, nutritious diet. Many people use vitamins as a type of nutrition insurance; just in case they are not receiving enough from their diet. In certain circumstances vitamin supplementation can be of assistance, but medical advice should be sought before using them.
Vitamins • The primary sources of these vitamins are fruits and vegetables, wholegrain breads and cereals, some lean meats and dairy products. Meeting energy requirements by focusing on foods that are rich in nutrients and carbohydrates and choosing from a range of different foods will ensure athletes are naturally increasing their vitamin intakes and meeting their requirements. In terms of sports performance, dietary deficiencies in vitamins occur very rarely in athletic populations. Usually athletes who restrict energy intake or food choices for long periods of time are those at greatest risk of vitamin deficiencies.
Vitamins • When an athlete supplements high levels of vitamins (specifically the antioxidant vitamins A, C and E) this helps the body deal with the stress, hence lowering the amount of stress the body actually experiences. With a reduction in stress, there is potentially a corresponding reduction in the adaptation the body has to that exercise. So supplementing with vitamins may actually hamper training adaptations, leading to reduced performance gains over training cycles. If an athlete and his or her coach think that a vitamin supplement may be necessary it is important that they consult a doctor or sports dietician to ensure it is suitable to support the athlete’s training goals.
Minerals • Minerals include calcium, potassium, iron, sodium, phosphorus, magnesium and chloride. Minerals are important to cellular functions, such as muscle contraction, fluid balance and maintenance of energy systems. Athletes usually focus on mineral intake in relation to exercise related losses. These are mainly associated with those lost through sweat (mainly sodium).
Minerals • Usually performance will not be improved by taking large doses of minerals above the standard recommended intakes. Some athletes may be at risk of mineral efficiencies in certain situations. Iron and calcium are two minerals that are considered essential for athletic performance and so dietary intakes of those need to be adequate. As with vitamins, mineral deficiencies usually occur in relation to inadequate energy intake or from the restriction of particular food groups, such as red meat or dairy products. Mineral supplementation should not be undertaken without clinical evidence of a deficiency.
protein • Because amino acids are critical for growth and repair, many athletes have attempted to increase their protein intake to improve muscle repair and increase muscle growth. As mentioned previously, large quantities of protein are not required to increase muscle mass. In fact, most athletes consume more than enough protein within a high energy diet to meet their needs. Athletes typically focus on protein intake at the neglect of total energy intake. Without a suitable energy intake and training program, muscle tissue growth will not occur.
protein • Protein supplements usually come in two forms. • isolated proteins sold as protein-only powders (such as WPI or whey protein isolate) – protein in a pure form. • protein mixed with a number of other nutrients to enhance muscle growth (such as carbohydrate) – combination protein + other substances.
protein • Athletes often consume protein supplements under the misconception that extra protein will enable the body to build muscle tissue faster. In fact, at any one time the body can utilise only a small amount of protein to build muscle tissue and the rest is used in other bodily processes. This means protein consumed above this small amount will not aid in muscle tissue growth and is often wasted.
protein • Although protein powders are convenient and easy to use, they are no better than whole-protein food sources. Any claimed benefits of protein powders can be far outweighed by increasing energy intake suitably, and planning food availability to ensure nutrients are delivered when needed by the body.
protein • Milk is one of the best all round protein-recovery and muscle-building foods; it is cheap, readily available and great tasting. It contains two different proteins (whey and casein) that work synergistically to increase muscle protein synthesis and reduce muscle protein breakdown. It also contains carbohydrate for energy, as well as other nutrients that are essential for muscle tissue growth and repair.
caffeine • Caffeine is a central nervous system stimulant. It is commonly consumed in tea, coffee, cola drinks, energy drinks and chocolate. High levels of caffeine are not necessary for sports performance. Caffeine has a number of effects. Caffeine: • increases heart rate and can affect heart rhythm • relaxes smooth muscle (such as intestinal muscles) • can produce symptoms of anxiety in high doses • decreases an athlete’s rating of perceived exertion—athletes feel as though they are performing more easily than they actually are. https://www.sportsdietitians.com.au/factsheets/supplements/caffeine/
caffeine • Caffeine is absorbed through the intestines. Its effects can be felt in as little as 30 minutes but the majority of caffeine’s ergogenic effects are seen after 45–60 minutes when blood levels of caffeine peak. In the past, consumption of large amounts of caffeine (>12 micrograms/millilitre of urine) was considered illegal in international sport and banned under the WADA code. Caffeine has recently been removed from the WADA banned list. • New evidence has shown that high doses of caffeine (>6 milligrams per kilogram body weight) are unnecessary to see performance enhancement and generally result in adverse side effects. In fact as little as 2–3 milligrams per kilogram body weight is enough to potentially improve performance.
caffeine • The diuretic effect of caffeine is a concern held by many athletes but is often over-exaggerated. Caffeine is a mild diuretic but during exercise this diuretic effect falls off dramatically and will not exacerbate dehydration during exercise. The current boom in the energy drink market has meant there are products available that provide well in excess of 2–3 milligrams of caffeine per kilogram body weight in one drink. A level above this may be detrimental to some athletes as it can increase anxiety and make them feel ‘jittery and unsettled’ before competition.
caffeine • Athletes need to be aware of individual variation in the benefits of caffeine. Athletes who are highly sensitive to caffeine need to be wary of the timing of its intake and weigh up the benefits compared to the side effects. As indicated in Figure 7.9 (next slide), ingesting too high a dose of caffeine may impair visual information processing. Athletes should also be aware that caffeine may reduce sleep quality and quantity, which may adversely affect their recovery.
creatine products • Creatine is a compound that occurs naturally in the body. It is found mainly in the muscle tissue in the form of creatine phosphate, which provides a ready source of ATP to the working muscle in times of high demand (such as in high-intensity anaerobic exercise). At times of lower demand (that is, at rest or during lower-intensity or more aerobic exercise), creatine is resynthesised to creatine phosphate ready for the next high intensity bout.
creatine products • The average person requires approximately 2 grams of creatine a day. In a normal training diet an athlete’s dietary intake will be approximately 1–2 grams per day and the body has the ability to produce the remainder. The main source of dietary creatine is animal products, such as meat. Dietary intake increases in athletes who consume large amounts of meat products in their diet (such as young male team sport athletes). Athletes attempt to increase the body’s stores of creatine by supplementation.
creatine products • The body has a maximum, or ceiling, amount of creatine it can store and once this maximum is reached it will break down the excess creatine into creatinine and excrete it through the urine. Some athletes naturally have higher creatine stores than others, and therefore reach their ceiling very quickly when they start supplementing. These athletes are often referred to as non-responders as they often see little or no benefits/bodily changes during creatine supplementation. Athletes who have low dietary intakes of creatine (such as vegetarians) often report large bodily changes (mainly weight gain) and performance benefits from creatine supplementation.
creatine products • By supplementing creatine, athletes are trying to enhance the efficiency of the ATP-PC system to provide energy during high-intensity activities. • Studies have shown that while creatine is able to improve the recovery rate (faster resynthesis of ATP) it does not extend the length of time a performance can be maintained. • Due to its ability to improve resynthesis rates of ATP during short rest periods, creatine supplementation will not usually improve one-off efforts. • Instead, creatine supplementation is used in sports where training sets incorporate very high intensity explosive efforts with short rest periods (over 30 seconds) between bouts of exercise.
creatine products • Creatine supplementation is usually taken in two ways to saturate the muscle tissue stores. Athletes either load with 20 grams (four 5-gram doses spread over a day) per day for five days (rapid load) or 3 grams per day for a month (slow load). Athletes will choose the differing loading protocols based on the goal of the training and the side effects that creatine supplementation can have.
creatine products • Creatine monohydrate is the original form of creatine researched and has the most scientific support. Newer versions are being marketed as superior but to date none has been shown scientifically to be more beneficial than creatine monohydrate. The consumption of creatine with carbohydrate has been shown to improve its absorption and storage in muscle tissue. It is therefore recommended that athletes take creatine with a source of carbohydrate. Once the muscle tissue stores of creatine have been saturated a smaller maintenance dose of 2–3 grams per day is adopted to ensure the maintenance of the high stores. Once an athlete ceases creatine it usually takes about 28 days for the muscle stores of creatine to return to pre-loading levels.
creatine products • While there are some benefits to creatine loading, one of the main negatives is weight gain, which is generally in the range of 1–2 kilograms over the loading phase.This occurs due to cells in the body retaining extra water as creatine storage increases. This can be a concern to athletes who want the benefits of creatine but do not want to carry extra ‘dead’ weight.
creatine products • Although many athletes believe creatine is beneficial in all situations, it must be remembered that it is a highly specific fuel source. Creatine will not be beneficial for athletes who are not already consuming suitable energy and macronutrient intakes. • It is likely to only be of benefit to athletes who are undertaking explosive short-duration activities with short rest periods in between, rather than one off sprints or endurance events.
Questions to complete • Identify the common vitamins and minerals.
Questions to complete • For the vitamins and minerals identified in the previous question: a explain their function within the body b identify the foods they can be found in naturally.