I don't want the mass to slow down my hundred meter time! But I want it to help me in rugby. I want the strenght to help me in both ruby and athletics - I am turning 16 jan 2013 please Help!!! (Twitter @toodopeandy)I don't want the mass to slow down my hundred meter time! But I want it to help me in rugby. I want the strenght to help me in both ruby and athletics - I am turning 16 jan 2013 please Help!!! (Twitter @toodopeandy)

Join a swim club swimming is the best sport for building muscle strength and endurance.

I'm not an expert in working out, but I would say you want definition. So, at the gym do low weights but high repetitions.