If you ask me they are a fad and it's only a matter of time that someone realises they knack your joints up by over stretching tendons (tennis elbow anyone?)
Like most things sensible weights and reps will do exactly what you are looking for
Strengthen core = squats
Keep body fat down = run or cross train
Originally Posted by oROSSo
give the 4kg to your daughter or something!
They say an average sized man should start around 16kg
I've got a 16, 20, 24, 32 and 40.
Mainly used as conditioning but very versatile