fractures, but in the long term difficulty conceiving and the early onset of osteoporosis are also possibilties.In the 1970s experts thought amenorrhoea was linked to weight loss or low body fat but that view has since changed. Now an energy imbalance

marathon or other endurance race. Carbohydrates are, after all, the top choice for fuel and the best energy source. "Runners should be taking in about 55 to 65 per cent of their calories in the form of carbohydrates,"says RW Nutrition Editor Anita Bean

for runners to work towards."Bandu believes that many runners overlook the mile - and the training it demands - at their cost. "Training for the mile challenges all the energy systems," she says. "If you can learn to run faster over a shorter distance

to four miles to take the edge off your pent-up energy so you’ll sleep better that night. Mental Preparations “Confidence should be the focus of the final week,” says Hays. “But you may still experience anxiety. If so, remind yourself that you

training load and tuck into plenty of carbohydrates. This will allow you to draw on fully-stocked glycogen levels for energy during the run.Aim to finish eating by 7pm - this will give your body time to process everything you've eaten.Slow-burning complex

antiquated thought now that we need to eliminate fat to lose weight," says Jonny Bowden, author of The 150 Most Effective Ways to Boost Energy Naturally (Fair Winds Press, £14.99). In fact, eating moderate amounts of fat can help you lose weight. The key

to match your training energy output. However, as your training volume increases and then tapers, so should your food intake. Planning your pre-race diet needn't be a nutritional nightmare: here are 25 handy do's and don'ts to help get you started

there is a balance of vegetables, salad or fruit and carbohydrate and protein.The problem: You pack in proteinIf you are consuming a high amount of protein, you might be cutting down carbohydrate-rich foods to stay within your energy requirements

that a meal of carbs plus protein (C+P) after exercise boosted the resynthesis of muscle glycogen (your body’s best energy source) more than carbs alone (C). This was an important finding because glycogen resynthesis is the gold standard for measuring

, but the day before, jog two to four miles to release some of your pent-up energy.For sub-marathon races, tapering for between three and seven days can be beneficial. During this time, cut your usual run distances in half, and if you do any speedwork, make