Reese Witherspoon's svelte figure is down to a revolutionary exercise class called YogaHop.The 'Walk The Line' star, who has been showing off her slim physique in a series of tight dresses, is following a new spiritual workout programme invented by her personal trainer Matthew Reyes.Matthew said: "Most people think yoga is all granola and hippies, so I love to explain how YogaHop is not like that. Imagine all the benefits of Hatha Yoga, then add chart music that will have you bouncing into the poses."Reese, 32, has also taken her boyfriend Jake Gyllenhaal along to a couple of the 90-minute classes, which she tries to attend two to three times a week.Matthew added to Hot Stars magazine: "Reese needs to stay looking great and be physically strong. There is quite a bit going on in her life so time is precious. She sees YogaHop as a one-stop-shop for all her body, mind and emotional needs."Reese is a fantastic student and has been an inspiration for many to embrace my yoga style as a means for fitness without needing a gym."