A:  High rep training isn’t a concept from Mars these days – it’s actually more than norm with the average with upper level bodybuilders.  Guys like Cormier, Wheeler and Ray who had a big heyday in the 90s would often do 5 or 6 sets of 30 reps using 315 on the squat bar or 50 reps on a moderately loaded leg press.  Cormier has gotten his physique looking stellar in the past few years in just that way. Mass is something you can get from high reps, despite the old myths. And believe it or not, mass can be easily had by doing leg extensions. You can get mass, in fact, anywhere if you are intense enough and really work and feel your legs.  Extreme amount of time under tension is why cyclists and skaters have powerful legs. It isn’t just the sprinter. Exposing the legs to this kind of workout will double the amount of mitochondria developed in no time, and facilitate capillary growth and hypertrophy in ways that lower intensity workouts cannot. Both quads and deltoids benefit from this type of workout.