Athletes who regularly undertake tough workouts, like several sets of tennis or long distance runs, may need to supplement their magnesium intake by eating plenty of leafy green vegetables, whole grain, lean meat and low-fat milk, advises the Reebok Aerobic Information Bureau.

According to a study conducted at Brigham Young University, heavy cardiovascular workouts deplete the body's level of magnesium, which is necessary for muscle and nerve functions. Too little magnesium can lead to convulsions and spasms.- TO HELP MAINTAIN your weight, the Reebok Aerobic Information Bureau advises that you need to burn approximately 1,500 calories a week in exercise (depending on body height, size and structure). Here are some suggestions for fat burning routines:

-Run for one hour at 6 mph three times a week.

-Walk for one hour five times a week.

-Or skip rope for 30 minutes 6 times a week.