Protein shakes and protein powder supplements promise youngsters biceps,triceps and six packs. Many think a high-protein diet guarantees an increase in muscle mass.
Athletes should get 10-20 per cent of their daily kilocalories from protein. The recommended daily allowance for protein is 0.8g per kg of body weight. It could rise up to 1-1.5g/kg body weight for periods of intense training,strength training,weight-lifting and body-building. But there is little evidence substantiating the need for higher protein intake. As long as athletes eat a nutritionally balanced diet,they dont need extra protein except during intense training.
Researchers suggest athletes consume 4 gm of protein for every 10 gm of carbohydrates. About 10-20 gm of high-quality protein (low-fat milk,fruit smoothies,cereals and fruit yoghurt) along with carbohydrates (50-60gm) is recommended.
Weight training,not eating extra protein,is the key to building and strengthening muscle. The only way to build bigger,stronger muscles is to exercise them. To fuel heavy weight training,the body needs extra calories,especially from carbohydrates. According to recommendations,500 kcal/day results in half a kilo increase in lean body weight per week during resistance training.
If you take excessive amounts of protein,the extra calories will be stored (as fat) or burned. It can also lead to over-straining of kidneys and long-term metabolic problems.
Excess protein intake enhances diuresis (loss of body water) as the body excretes excess nitrogen (urea and ketones) through urine. This causes mineral losses and increases the risk for dehydration. High-protein diets are often high in cholesterol and may contribute to obesity,osteoporosis,heart disease and cancer.
Individuals with a family history of liver and kidney problems and diabetes are at higher risk of adverse reaction from excessive dietary protein. Gout,a painful inflammation of joints,may be aggravated by high-protein diets as uric acids accumulate in joints.
High-protein diets that propagate reduction in carbohydrates are unsuitable for high-endurance activities. These diets deplete muscle glycogen stores and thereby impair the ability to undertake prolonged,high-intensity exercise.
High intake of single amino acid supplements may impair absorption of other amino acids. Also,the amount of amino acids contained in supplements is much less than that found in protein-rich foods such as dairy products,egg whites,lean meat,poultry,fish and legumes. Excessive reliance on such supplements causes deficiency in vitamins and minerals found in protein-rich foods,such as iron and zinc in meat,fish and poultry. Consumption of individual amino acids suppresses appetite,precipitates tissue damage,contributes to kidney failure and osteoporosis and causes gastrointestinal problems.
Many commercial supplements contain high-quality protein such as milk,whey,egg or soy protein,provide a balanced mixture of protein,carbohydrate and fat for additional calories,and vitamins and minerals. But they must be taken under the supervision of a qualified professional.