> There's absolutely no way you can stress the nervous system and build muscle and bone density as efficiently as with lifting weights. I'm not sure about that

> There's absolutely no way you can stress the nervous system and build muscle and bone density as efficiently as with lifting weights. I'm not sure about that - have you looked at the strength required for some of the exercises people do on gymnastics rings? Things like ring planches, maltese, victorian cross (once thought to be impossible) etc.