Dudes in the iron game love to debate the merits of lifting low volume and heavy weights vs. high volume and lighter weights. Though clearly there are benefits to both—low volume saves time, high increases endurance (and builds every bit as much muscle tissue)—a new study from the University of Nebraska-Lincoln found that lifting heavy is key to quicker strength gains.

Three times a week for six weeks, 26 male subjects did legs extensions to exhaustion with either 80% or 30% of their max. At the end, heavy lifters could hoist about 10lbs more for their max and generated about 2.35% more force compared with the low loaders’ .15% improvement. So rock both for the smartest gains.