Juggernox and Andronox I have so many great memories growing up and hitting the gym. I have been in the gym off and on since I was 15 years old. We will discuss muscle building at any age and give some general advice for quick results. It should be known that when I say at any age I do not mean young children. I think that the earliest you should be building muscle through weight lifting should be 15 or 16. You must let your body grow before putting too much pressure on it or there can be adverse effects.http://gomusclebuilding.com/juggernox-and-andronox/