Improving your diet is the initial step to good health and is essential for supporting a regular exercise plan
PEOPLE TODAY are more aware than ever before of the importance and benefits of good nutrition in relation to both health and fitness.
According to internationally renowned exercise scientist Prof David Costill, “aside from the limits imposed by heredity and physical improvements associated with training, no factor plays a bigger role in exercise performance than does nutrition”.
The importance of adhering to good nutritional practices cannot be understated. Whether you are a serious athlete or merely trying to improve general fitness, by applying simple nutritional principles can help you achieve your fitness and performance goals.
Improving your daily diet is the initial step to good health, and is essential for supporting a regular exercise plan. A healthy balanced diet is an integral part of any exercise programme, but it is often overlooked. It is an essential ingredient in maximising your ability to get fit and maintain a healthy lifestyle.
A typical healthy balanced diet is predominantly made up of three main nutrient groups – macronutrients – these are carbohydrate, fat and protein.
CARBOHYDRATE
Carbohydrates, which are stored in the body as glycogen in the muscles and liver and glucose in the blood, are categorised by their glycemic index (GI). Carbohydrates that break down quickly during digestion leading to a rapid rise in blood glucose have a high GI, whereas carbohydrates that break down more slowly leading to only a gradual release of glucose into the blood have a low GI.
Carbohydrate is the main source of energy used to fuel the body during exercise and sport. It is therefore important to include generous amounts of a variety of carbohydrate-containing foods at all meals and snacks.
FAT
Contrary to common belief, a certain amount of appropriate fats are an important element of any diet as they provide the energy and essential fatty acids necessary for normal body function.
Furthermore, scientific evidence suggests that there are no additional health or performance benefits to consuming a diet maintaining less than 15 per cent of energy from fat. Overall, balanced diets should provide moderate amounts of energy from fat, with saturated fat kept to a minimum and certainly less than 30 per cent of total fat intake.
PROTEIN
Protein plays an important role for recovery after exercise, muscle repair and helping to regulate the nervous system. In general, an individual consuming a varied diet will meet their requirements for protein without the need for protein supplements.
Good sources of protein in the diet include meat, poultry, fish, cheese, eggs, milk, nuts and pulses (peas, beans, lentils).
Care should be taken with the fat content of protein foods by choosing low-fat products and by grilling or baking in preference to frying.
To achieve a healthy diet it is important to have an appropriate balance of these key macronutrients, along with maintaining daily requirements of essential vitamins, minerals and water. When taking part in regular exercise, a person’s diet should be high in carbohydrate, low in fat and moderate in protein, as is consistent with healthy eating guidelines.
The internationally recognised nutritional guidelines for healthy active adults, taking into account personal circumstances and individual needs, is that of the daily calorie intake of a healthy diet should be high in carbohydrates (50-60 per cent), moderate to low in fat (25-30 per cent) and adequate in protein (10-15 per cent). Although these recommendations may be appropriate for general populations, more specific guidelines are available in the scientific literature for athletes.
Next week we will look at the specific dietary guidelines more closely and, in particular, current recommendations for nutritional intake both before during and after exercise for optimising recovery and enhancing athletic performance.
Dr Giles Warrington is a sport and exercise physiologist and lecturer in the School of Health and Human Performance at Dublin City University (DCU)