1.3 Energy use, diet, nutrition and hydration GapFill

A healthy, balanced diet is important to maintain good health and requires eating the correct proportions of nutrients to maintain healthy body weight. 

The ratio of macronutrients in a diet needs to be considered if a healthy lifestyle is to be maintained. The usual recommendations are for at least half of your overall calorie intake to be comprised of   mineralsfatsfibrecarbohydrates, as this is used as the major source of energy for physical activity and sport. Depending on activity levels, the percentage of this component might be even higher, as is the case for an endurance athlete who would take part in   weight gaincarbohydrate loadingweight lossglycogen loading for competition.   MineralFatCarbohydrateFibre intake should be kept below 30% of total calorie intake as excessive saturated forms can increase total cholesterol and act as a risk factor for chronic health conditions such as diabetes and heart disease. Nevertheless, this dietary component is still used as a source of energy when physical activity is completed at a low intensity, as in physical activities such as walking, gardening or even a light jog.   FatProteinFibreMineral intake is recommended at 15–20% of total energy intake as it cannot be stored in the body, and so the excess is likely to be converted into fat, and urea, which is excreted in urine. However, it is very important for muscle growth and repair, especially when taken   immediatelyany time24 hoursthe evening after resistance exercise for power athletes.

We also need micronutrients in order to maintain a healthy lifestyle. These are nutrients that are needed in smaller amounts.  MineralsVitaminsFatsCarbohydrates support the immune system, which fights infection and disease, but also facilitate the absorption and metabolism of other foods and supplements. They consist of water-soluble (B and C) and fat-soluble (A, D, E and K) groups.  MineralsVitaminsFatsCarbohydrates perform numerous roles, e.g. calcium for bone growth and strength, and iron for oxygen transport in the blood. Another important nutrient required as part of a healthy, balanced diet is  carbohydratemineralsfibrefat, which aids digestion of foods and facilitates bowel movements.

Hydration should be maintained during daily living to promote a healthy lifestyle. It becomes even more important in physical activity and sport since body water is lost at a greater rat|sweating|respiration|thirst|urination|energy expenditure|carbohydrate loading}, as the body tries to cool itself down to prevent an excessive rise in body temperature from limiting performance. General guidelines are to consume an additional 1 L of water for every hour of exercise, but factors such as a greater intensity of exercise and  rainyhotcoolwindy,   hailinghumidwetbreezy weather conditions should force the individual to consume more. A good guide is to weigh in before and after exercise, then whatever the difference is, consume 150% water plus electrolytes to rehydrate, assuming that 1 kg of body mass = 1 L of water. Inclusion of electrolytes will help retain water and prevent a large amount of it being passed in urine. If dehydration of >2% body mass occurs, performance will be impaired as blood will thicken and heart rate and body temperature will increase, leading to early fatigue. Dehydration of >5% could be dangerous to health and should be avoided. Maintaining hydration will ease the perception of effort and limit an excessive rise in heart rate, utilising a greater percentage of   mineralsfatcarbohydratefibre rather than the limited store of   fatvitaminscarbohydratefibre for energy.