Sports Nutrition

All athletes need a diet that provides enough energy in the form of carbohydrates and fats along with essential protein, vitamins and minerals. This means a diet containing 55-60 % of calories from carbohydrates (10 to 15 % from sugars and the rest from starches), no more than 30 % of calories from fat and the remaining (about 10-15 %) from protein. That translates into eating a variety of foods every day – grains, vegetables, fruits, beans, lean meats, and low fat dairy. Fluids, especially water, are also important to the winning combination as dehydration can stop even the finest athlete from playing his or her best game.

Carbohydrates

Dietary carbohydrates are a vital source of energy in the body, supporting optimal effort during both aerobic (cycling, running, swimming) and anaerobic (weights) activity.

Carbohydrates can only be stored in very limited amounts within muscle and liver cells as a compound called glycogen. Glycogen is the storage form of glucose, and it is called upon when muscles need more fuel.  Glycogen is needed for both endurance and strength events, but the human body has a limited capacity to store it.  So, even though athletes need a lot of it, we only have a limited supply. This is where you may have heard the term ‘Carb loading’ before as some training regimes see it as crucial to keep this glycogen ‘fuel tank’ full by making carbohydrates a main part of the foods primarily consumed, and by eating carbohydrates before, during (in some cases), and immediately after exercise. Because glycogen is only efficiently stored when an athlete is well hydrated, it is also important to make certain that plenty of fluids are consumed while eating carbohydrates.

When glycogen stores are fully loaded, they function as a fuel source for strenuous activity, but will become depleted as exercise continues beyond 60-90 minutes. Carbohydrate nutrition is vital for refilling glycogen stores to fuel ongoing endurance activity.

The current recommendation for daily carbohydrates (CHO) consumption is 5 – 7g CHO/kg/day for the general athlete and 7 – 10g/kg/day for the endurance athlete. Consuming CHO immediately after exercise accelerates glycogen repletion because there is increased blood flow to the muscles. Sufficient CHO ingestion over the next 24 hours is also important. It is recommended to consume 1 – 1.5g of CHO/kg of body weight within 30 minutes after exercise and then again at 2-hour intervals for the next six hours. Carbohydrates also play an indirect role in muscle building. When carbohydrate is consumed together with protein in optimal amounts, the presence of energy-giving carbs helps block the wasteful conversion of protein into energy, ensuring maximum protein is freed up purely for muscle development. This is particularly important within the first half hour after exercise, a critical period of feeding in the recovery process.

Protein

Protein is the essential building block for muscles, bones, vital organs, and all other tissue in the human body while also having important functional roles in hormone and enzyme control. Protein also contributes to sustained energy by slowing the absorption of sugars into the bloodstream

The requirement for protein is dependent on total energy intake, the amount of training an athlete does, and the intensity of that training.  Good sources of protein include meat, poultry, fish, and eggs. However, vegetarians can obtain adequate protein by combining non-meat items. For instance, combining legumes (beans) and cereals (rice or corn) creates a protein combination of high quality.

Proteins consist of approximately 22 smaller units called amino acids. Eight of these are essential amino acids, meaning that, although necessary for survival and optimum functioning, they cannot be made in the body and can only be obtained in the diet. Three of the essential amino acids have significance for the athlete (Valine, Leucine, Isoleucine) and are known as branched-chain amino acids (BCAAs), which have integral roles in muscle development and maintenance.

If you consume enough energy from carbohydrates, then the protein you consume will be used for all the valuable protein related functions, such as synthesis and maintenance of muscle, synthesis of creatine, and the creation of hormones and enzymes.  However, without enough carbohydrate energy, the consumed protein will be ‘burned’ as fuel rather than used for these other critical functions.  Burning protein as fuel causes increased water loss that can increase the risk of dehydration (a major factor related to poor performance in athletes!)

Fats

Fat is a useful energy source during moderate or low intensity exercise and plays an important supporting role in energy production by acting as a back-up source when restricted carbohydrate stores are depleted. Dietary fat is also important for absorbing the fat-soluble vitamins (A, D, E and K) and plays a role in other functions including joint health, hormone production, heart health, brain function, mood and focus.

Like protein, some fats are essential for key biological processes but cannot be made in the body and must be supplied in the diet. These are known as essential fatty acids (EFAs) and include omega 3s and omega 6s. Omega 3s are particularly vital for athletes, as they perform functions that help create the environment for optimum muscle recovery. They assist by preventing muscular inflammation, producing and regulating the hormones that trigger muscle growth and repair, and maintaining cellular integrity to ensure all muscle cells take in the nutrients they need to function and grow.

Dietary fat can be of both animal (dairy, meat) or plant (oils) origin. Fish and flaxseed are good sources of Omega 3 fatty acids, while Omega 6s can be found in corn, soy, canola and sunflower oil.

Water

In addition to energy requirements, hydration is a major nutritional factor influencing performance and endurance. The demand for water intake is greatly increased during exercise, particularly on hot days as a result of sweating.

Formulated sports drinks provide additional nutrients, such as carbohydrate and electrolyte content to assist hydration. By replacing the electrolytes lost in sweat, sports drinks containing the five important electrolytes (sodium, potassium, magnesium, calcium and chloride) help to promote fluid balance and optimal hydration.

Timing

There should be adequate time for food to leave the stomach before starting exercise. Because fats cause a delay in stomach emptying, fat in the pre-exercise meal should be kept as low as possible. Ideally, a high-carbohydrate meal should be finished 3.5-4.0 hours before exercise if the meal is large; 2.0-3.0 hours before exercise if the meal is small. Light, carbohydrate snacks may be consumed within 1 hour of exercise and sports beverages may be consumed at any time before and during exercise.

Supplementation

In practice, you won’t always be able to cover all bases with regular foods, which is why some people opt for ready-formulated performance nutrition. Supplementation can give you that elusive edge in performance and may help address deficits in your diet that naturally result from hard training and competition. In addition, sports supplements are specially formulated to contain more concentrated amounts of the active ingredients needed to obtain maximum performance benefits. Here are a few of the most popular supplements;

Glutamine  - the most abundant amino acid in muscle tissue, yet it is easily depleted during strenuous activity. Benefits are;

• Supports muscle growth and aids athletes’ goal for lean body mass.
• Aids recovery post exercise & recovery
• May shorten recovery periods post exercise
• Helps build lean muscle tissue

Creatine Monohydrate - creatine is actually a nutrient found naturally in our body and it’s made from the combination of 3 amino acids (arginine, glycine and methionine) Benefits are;    

• Supports lean body mass, strength and muscle function
• Supports recovery post training
• Supports performance during intense exercise and resistance training
• Is used in the body to metabolise fat into energy

Carnitine - An essential fat metabolising amino acid, necessary for the metabolism of fats in the body. Carnitine contains nutrients that play a vital role in the production of cellular energy, which may assist with stamina and athletic performance and support daily energy levels. Benefits are;

• Helps support stamina and endurance.
• Helps to maintain healthy weight composition.

Tribulus - An herbal formula, to support the stamina and endurance needed during intense physical activity. Tribulus works by maintaining the production of testosterone levels in the body. Testosterone is a naturally occurring hormone associated with:

• Muscle growth
• Strength
• Support for endurance, stamina and athletic performance

Whey Protein Isolate (WPI) - Whey, a by-product of cheese manufacture, is processed to eliminate as much fat and lactose as possible, leaving a very high protein content (90% – 96%) compared to other protein sources. Benefits are;

• Has a very fast rate of absorption (ideal for immediate post-exercise window)
• Has a very high BCAA content for muscle building
• Has a very high impact on satiety (appetite satisfaction)
• Is ultra lean (low in carbs, fat) for weight management

Whey Protein Concentrate
(WPC) - As a result of ultra-filtration manufacturing process, WPC is an excellent source of protein, (80% +). WPC may contain small amounts of fat, although much of the lactose and minerals have been removed. Benefits are;

• Fast rate of absorption
• High BCAA content for muscle building
• High impact on satiety

Hydrolysed Whey -  speeds the digestion and absorption rate by partially breaking down the complex protein into smaller chains of amino acids called peptides. Benefits are;

• Most rapid rate of absorption
• Very high BCAA content for muscle building
• Very high impact on satiety (appetite satisfaction)
• Ultra lean (low in carbs, fat) for weight management & getting lean

Soy Protein Isolate -  A high-quality vegetable source of protein. Benefits are;

• Low in fat and cholesterol free
• Moderate rate of absorption
• Ideal as a complete protein source for vegetarian athletes and those with dairy allergies

At the end of the day, sports nutrition is very specific to you as an individual and your training goals. The above is just a general guide, but I do hope that it at least gives you a foundation to build on with your trainer or health practitioner. All of this strength and power talk, I now feel guilty that I didn’t go for my run as intended this morning…as Nike so aptly put it…Just Do It!

Live well, live long, live naturally

Renée x