There is no better system .. use both a bit of volume and throw in intensity techniques now and again to shake it up. You can stimulate muscle with less sets and Heavy duty training but your body will suffer in the long run with this causing a Heavy duty Burn out...and sore joints. Alternate both and see what works for YOUR body, not anyone elses on here...only YOU will know and feel it. some swear by HIT training and others go for high volume but like we say.."there is more than one way to climb a mountain"