In-line skating provides a great low impact workout which some studies have suggested provides the same level of aerobic activity as running or even riding a stationary bike. The calorie burn will depend on your size, the effort you put in, and the route you take, but it is estimated that half an hour skating could burn in excess of 200 calories.

Inline skating develops muscles in the entire upper leg, rear end and hip, as well as the lower back. Muscles in the upper arms and shoulders are also developed when arms are swung backwards and forwards while skating and you can increase your calorie burn just by swinging more vigorously.

Image: Flickr/eneas