I've been reading a lot about the 30 day shred, which I have just learned is a workout DVD. I like the idea of 20 min workouts but from reading reviews online it is a v.tough workout. I have around 4 stone to lose and have not excercised in years properly. My question is does anyone in their experience know if it is suitable for someone like me with so much weight to lose and unfit or would it just kill me off.