If you swim several times a week and can't lose weight, a study from Florida University might have the explanation for you. It occurs that the problem isn't in swimming itself. Swimming is aerobics that contributes (burns) about 300 kcal in half an hour. But the problem is in the water temperature.

Volunteers in this research swam for 45min. Half of them in water temperature of 20C and the other half in 33C. After swimming, trays with food were laid in front of the volunteers. It appears that people who swam at the cooler water ate more.

Dr. White explains: "The cold water is cooling us, and as a result the appetite grows to warm our body." As a result those who want to use swimming to lose weight should swim in warmer water, thus not affecting the appetite.