This study looked at two types of weight training for young men who already lift weights. It found a small hint that powerlifting-style training might help build more squat strength than bodybuilding-style training over 8 weeks, but the results aren't clear enough to be sure—bigger studies are needed.

Lifting heavy weights with longer breaks between sets makes young men stronger faster than lifting lighter weights with shorter breaks, based on an 8-week study.

Lifting heavier weights for fewer reps makes well-trained young men stronger faster than lifting lighter weights for more reps, especially in exercises like squats and bench presses.

Lifting heavier weights for fewer reps makes your legs much stronger than lifting lighter weights for more reps, but both types of training help your upper body a little bit too, and this might work differently for different muscles.

If you're a young guy who already lifts weights, doing heavy lifts with longer breaks might help you get stronger at bench press faster than doing lighter lifts with shorter breaks, even if you do the same total amount of work. But the difference might be small, and we need more research to be sure.

Lifting heavy weights with fewer reps and longer breaks might cause more joint injuries than lifting lighter weights with more reps and shorter breaks, especially in young men who are already fit.