Ruth is a leading sports dietician and a member of the British Dietetic Association and Health Professional Council. She is also an advisor to Sportscotland's Institute of Sport, specialising in helping athletes of all levels prepare nutritionally

to salads and cheese boards and a perky accompaniment to meat. Pears also make great healthy puddings, whether you poach them or add a dash of cheeky chocolate. Cooking times vary depending on the variety and ripeness of the fruit, but pears generally make

an about-turn, eschewing starches and relying instead on vegetables, fruits and lean meats as fuel.Consider what follows as a challenge to the ideas about nutrition you've been exposed to for years. Follow the advice and you'll stay lean and strong

to swallow.The science: Contains a mix of fast- and sustained-release carbohydrates (80:20). The added antioxidant vitamins and amino acids are useful for the diet in general, but you don’t particularly need top-ups during normal exercise.Science in Sport Go

you burn daily. (An average male burns around 2,500kcal a day, a runner covering five miles a day more like 3,000kcal.) In general we need two to three litres of liquid a day – half from food and half from fluids. This is a minimum: if you live