Major sports brand Reebok have claimed that their new line of Easytone trainers can tone your hamstrings, calves and bum nearly 30% more than regular trainers just by walking in them. They claim the trainers can "train muscles your trainers never knew you had."

The glamorous brunette is the face of the new line of trainers said to improve tone and strength in the legs and bum via a unique unstable sole. She will also be their spokeswoman for their new Jukari Fit to Flex workout. Reebok created the workout with inspiration from the performances of Cirque du Soleil, it targets core muscles and the upper body by using a light elastic band that can be used in a variety of ways.

Leading the test was John Porcari PhD, who agrees that the trainers should work in theory as they create instability that the body attempts to counteract thus making the muscles work harder. The shoes are based on a curved sole which creates an unstable surface which forces the wearer's body to constantly struggle to find equilibrium.

The entire Reetone range was tested on two groups, the first aged 19 to 24 who were put through exercise trials and had muscle activation, heart rate and caloric expenditure measured.

You are able to wear the trainers, flip flops or sandals whenever you want and as long as you're standing, they are working your muscles. It's like sitting on an exercise ball all day rather than an office chair.

So if you're off doing the weekly shop or just walking around the workplace, your legs will be in constant workout. The company commissioned a study to determine how effective the trainers were and the results noted at least an 11% increase in muscle activity in the calves and gluteus during simple activities. However none of the subjects notices a difference in aching or physical exertion.

Consumers have so far gone mad for the Reebok easytone range and there is rumour of further, more casual models to be added to the popular easytone trainers