Explain the relationship between diet and exercise

In his early days at Arsenal, Tony Adams ate far to much steak and chips and junk food, His performance only improved when he switched to a diet of fish, chicken, vegetables and fruit. The days when professional footballers ate a steak before a game in the belief it would aid strength and fitness are long gone. Much attention is now devoted to ensuring athletes take in the right food and drink. Nowadays, getting it right can make the difference between winning and losing.

Food is the body's fuel which provides energy to allow our muscles to work. Without food or drink the body cannot function.

Without the right foods there is no energy, so lack of food or poor quality of food will cause footballers to under perform.

In general, the body's energy supply comes from the three main types of foods- proteins, fats and carbohydrates.

Fatty foods contain the most energy but are useless as an energy source during high intensity activities associated with football (sprinting). They can only be used during lower intensity aerobic exercises such as jogging.

Carbohydrate foods contain energy which can be used to fuel the muscles for prolonged aerobic activities and for shorter anaerobic activities such as sprinting. Therefore, carbohydrate foods are ideal energy sources for footballers.

Protein foods are used by the body after 45 minutes of exercise which again is ideal for football.

Research shows professional outfield players run about 5-8 miles in a game and are in personal possession of the ball for a total of 3 minutes. As a result they use up huge amounts of carbohydrate energy. These carbohydrates must be replaced after the match. However two days prior to the match professional footballers increase the amount of carbohydrates they eat. In this way their muscles are fully prepared for the exercise within the match.

Outline the role of macro and micronutrients, vitamins, minerals, dietry fibre and water in an athletes diet

It is also very easy to dehydrate during exercise especially during summer months. Drinks which are very fizzy or very cold should not be drunk during periods of exercise as they often lead to stomach pains. Also drinking great quantities should be avoided for the same reasons, the rule 'little and often' should be followed. Well known sports drinks like Isotar, Gatorade and Lucosade sport are ideal, but water is also the best liquid to consume while exercising. Loosing as little as 2 percent of your body weight can hinder your performance on the pitch. Therefore it is recommended that you drink water before, during and after exercise,

"After exercising in hot humid environments for just one hour a water loss of up to .5lbs per mile may occur. To replace fluid loss under these conditions, you would have to drink one cup of water (8oz) every mile or 6-8 minutes"(Nieman,1990,www.calstatela.edu).

Fibre also has a big part to play in an athletes diet, there are two types of fibre- insoluble and soluble. An added benefit of fibre is its ability to help control blood-sugar Levels. Soluble fibres delay gastric emptying, which slows the absorption of glucose. Stable blood-sugar prevents carbohydrates in the diet to be stored as fat in the body, therefore its still helpful for a footballer due to the fact they get most of there energy from carbohydrates rather than fats. Insoluble fibre is associated with moving food through the digestive tract and has a well deserved reputation for promoting regular bowel movements.

Briefly explain the methods used to investigate the links between diet, health and fitness.

Methods used to investigate the links between diet, health and fitness are nutritional research studies which are driven by media reports of new diet health findings from single studies. These single studies rarely provide the final answer and lead to contradictory advice, also contributes to confusion about how food choices influences their health. There are basically two types of nutrition research studies: observational and experimental. Observational studies measure dietary intake and fitness in groups (e.g., ecologic studies) or individuals (e.g., cross-sectional, case-control, and cohort studies). Among observational studies, cohort studies provide the strongest evidence of a link between diet and fitness. In this type of study, dietary information is obtained from individuals in a large population which is followed over time to observe the development of there fitness.

Cohort studies indicate whether individuals with differing dietary intakes vary in their levels of fitness.

Experimental studies include randomised controlled trials (RCTs) and basic research experiments (e.g., laboratory animal studies). Basic research experiments can help to identify diet-fitness relationships. However experimental animal findings cannot be readily compared to humans. A relationship between diet and fitness becomes more clear when relevant data from several different types of studies are consistent. Different diets have different effects on your performance, each sport is also different and requires different kinds of diets to enable them to reach there optimum performance. As I stated earlier your diet can often distinguish between winning and loosing at the top level, that's how important your body's physical shape is to your performance.