Some find truth in the contemplation of a flowering lotus blossom; some in the ability of the proletariat to overthrow the boss class; some in the bottom of Jack Daniels' finest. Three times Olympic rowing coach Terry O'Neill believes in the Anaerobic Threshold and the Wave Principle of Training. Makes for a dull guy at parties but boy is he the man for a question and answer column. If you've got something you'd like him to contemplate, send it to [email protected] Bruce Harris: Your opinion, oh learned one, on diets. I am an active man, 45, relatively fit (very relatively). I exercise 5-6 times per week for about an hour and mix it up running, cycling, rowing and throw in some weights so I can look at myself in the mirror. Even so, I carry about 7 kilograms over what I should weigh realistically (95kg instead of 88kg at 6ft tall).What do you think of these protein diets where you dump carbohydrates because they make you produce insulin which then blah, blah, blah. I tried it for four weeks. The first week I lost 2 kg then nothing after that. It's not easy cutting out starches as pasta and rice are my favourites. My training seemed to suffer at times as I felt very weak with little energy and my times, especially rowing, were poor. Is that psychosomatic or were my fuel stores depleted?Also THE best music to row to is Ian McNabb's 'Fire Inside My Soul' and ' Be Prepared To Dream' . Fifteen magical minutes of inspiring rock even the titles are the business.Terry O'Neill: The question of diets is really quite simple. All food has a calorific value and all exercise has a calorific value. The calories in food are chemical energy and exercise is mechanical energy. The body converts the chemical energy in food to mechanical energy in movement. If you consume more calories in the form of food than you use in the form of movement then you can put on weight as this surplus is stored about the body. Conversely if you use more calories in movement than you take in as food then the shortfall will be made up from stored fat and you will lose weight.There are seven different nutrients the body needs to remain healthy, vitamins, minerals, fat, protein, carbohydrates, fibre, and water. These are all contained in a normal diet and, more importantly, in a form the body can deal with. Any diet that excludes any of these should only be followed for a very short time as they present a risk to your health.Cutting out carbohydrates from your diet could easily have made you feel tired and sluggish and a look at your blood sugar level would confirm this.You are a big bloke with a big appetite and this is the first thing to address. You don't need to cut out but cut down. Eat smaller portions and eat as slowly as you can by putting less in your mouth and chewing every mouthful 12 times. Eat often, 5 times a day so you don't let the hunger pangs build up. Sensible eating and regular exercise are the best combination for a healthy life style but it gets harder as you get old and your percentage body fat increases naturally.