http://fitness.mercola.com/sites/fitness/archive/2011/05/13/getting-fit-doesnt-mean-killing-yourself.aspx
Useful article here. It describes how to differentiate between an easy, moderate, and hard workout, and gives ideas about how many times a week you should be doing each.
Useful article here. It describes how to differentiate between an easy, moderate, and hard workout, and gives ideas about how many times a week you should be doing each.