17-07-2025
Does Rep Count Really Matter? Science Finally Takes a Side (and the Answer Might Surprise You)
The rep debate has been raging in gyms for decades. Should you lift heavy for fewer reps? Go lighter for higher reps? Can you even handle more reps and more weight? Researchers and gym bros alike have argued every angle, but new research suggests it doesn't really matter as much as we thought.
What actually matters is how hard you're pushing yourself. In other words, there's no one-size-fits-all approach. The key is training with enough effort, regardless of the rep range.
In the recent study published in the Journal of Science and Medicine in Sport, researchers split a group of forty-seven healthy young men randomly into three groups: a 10-repetition max group, a 20-repetition max group, and a control group that didn't train.
Each training group performed two training sessions per week for six weeks using only the muscles in their lower body. Arguably, the most important aspect of the study was that each set was completed to concentric failure, meaning they couldn't do any more reps with proper discovered that muscle mass increased in both training groups, with no real difference between those who did 10 reps to failure and those who did 20.
"These findings demonstrate that twice-weekly resistance training to failure, irrespective of whether 10 or 20 repetitions are used, simultaneously enhances mitochondrial oxidative capacity, muscle hypertrophy, and strength, underscoring the versatility of resistance training for performance optimization and interventions targeting improved metabolic health," the researchers said.
The bottom line? Rep ranges matter less than you think, at least in this case. If your goal is to build muscle, the key is pushing your body and following a program that lets you progress over time. That could mean adding reps, increasing weight, or shortening your rest between sets. It's all about applying progressive overload.
Both high- and low-rep training have their benefits. Heavier loads can help you hit the intensity sweet spot with less overall volume, while lighter weights often feel more approachable and allow some people to push harder. The best approach is the one you can stick with, so find what works for you and commit to it.
Does Rep Count Really Matter? Science Finally Takes a Side (and the Answer Might Surprise You) first appeared on Men's Journal on Jul 16, 2025