Sport Nutrition - meat or no meat?

When we exercise, we use our muscles, and when we eat meat, we are eating muscle. So it is not surprising that before the advances in sport nutrition that have taken place in the last 50 or so years, many people assumed that consuming meat was essential for anyone who exercised regularly, since this was seen as the logical way to prepare and refuel the muscles used during exercise.

Our energy comes from carbohydrate, fat or protein - muscle consists mainly of protein, with little (if any) carbohydrate. Scientists have shown that even for those involved in heavy training, including resistance training aimed at increasing muscle size and bulk, the maximum amount of protein that is needed on a daily basis is no more than 2 grammes per kilogramme of body weight. So for someone who weighs 80 kilogrammes, this equates to 160 grammes of protein a day - or only 100 grammes a day for someone weighing a much lighter 50 kilos. There is no evidence that consuming more than this will increase muscle size or strength, and as with any food, eating too much protein will simply result in eating more calories than the body needs, and a gain in body fat and body weight.

Since the amount of protein that regular exercisers need is probably not as much as most people think, the need to eat large amounts of meat is not as important as many have believed in the past. Indeed, it is perfectly feasible for most regular exercisers to obtain the protein that they need without consuming meat at all.

Foods that are high in protein include nuts, seeds, cheese, eggs and yoghurt. Fish is a high protein alternative to meat, as are foods such a tofu and Quorn. These latter two are manufactured foods - tofu originates from the curdling of soya milk, whilst Quorn is a meat alternative which is derived from a fungus that has a similar protein structure to muscle fibres.

For athletes still desperate to get their meat fix, choosing lean cuts or white meat such as chicken and turkey provide the best choice since their lower fat content means that they contain fewer calories

If we assume that the daily protein intake for someone who exercises and weighs 75 kilogrammes does not need to exceed 150 grammes, here are some examples of how this can be obtained without having to eat meat. The values given show the approximate amount of protein that is in 100 grammes of each product:

Cashew nuts - 18
Plain yoghurt - 6
Milk - 3
Cheddar cheese - 25
Eggs - 13
Tuna  - 30
Cod - 18
Quorn - 14
Tofu - 8

For comparison, chicken breast contains 21 grammes of protein per 100 grammes, whilst 100 grammes of grilled steak contains approximately 25 grammes of protein.

Of course these foods can easily be combined to gain the desired intake, and anyone concerned that they may not be eating the quantity of protein that they need can chose from a wide range of protein supplements that can complement their daily diet.

One protein supplement that has become increasingly popular in recent years is Whey protein. This is derived from the milk that is left after cheese has been produced, and is high in branch chain amino acids, which are used in muscle synthesis, and low in cholesterol. As a result, Whey protein is seen as a high quality source of protein, particularly amongst those who undertake regular resistance exercise.

In summary, protein is essential for muscle repair and to support exercise. However excessive quantities of protein are not needed, and whilst meat is one protein source, other non-meat foods and products are a great way of ensuring that the body’s protein needs are met.

John Brewer is the Professor of Sport at the University of Bedfordshire, and previously held the position of Director of Sports Science for GlaxoSmithKline. A Post Graduate in Sport and Exercise from Loughborough University, his research focussed on the influence of carbohydrate diets on endurance running performance.