I am working these days because I want to get in relatively decent shape for my health. One thing that has been helpful is 7 minute workout. It doesn't seem like much but you really work up a sweat in 7 minutes. I try to do two sets. The second set I use the equipment at my gym and do jump rope.
My fiancé told me that workouts only start to burn fat after 40 minutes. Has anyone else heard this?