A new study suggests that lifting lighter weights with higher repetitions can build muscle just as effectively as heavy weights with low reps, provided you train close to failure. The research, published in the Journal of Strength and Conditioning Research, compared high-rep, low-weight training to low-rep, high-weight training, with both groups working to failure. The results showed similar muscle size gains in both groups.
However, for strength gains, heavier weights with fewer reps proved more beneficial. A meta-analysis in Sports Medicine confirmed that while heavier loads are key for strength, working closer to failure is crucial for muscle growth. The study emphasised that proximity to failure—finishing sets within 0-5 reps of failure—is the most important factor for hypertrophy, regardless of weight chosen.
Another study in PeerJ found that both increasing repetitions and increasing load are effective strategies for increasing muscle mass. This means gym-goers can choose either approach based on their preferences or phase of training. For instance, bodybuilders in a cutting phase often use lighter weights with higher reps to reduce neurological fatigue, while those in a bulking phase may incorporate heavier lifts.
For optimal muscle growth, experts recommend aiming for 8-15 reps per set and finishing 0-5 reps short of failure. For strength, heavier loads with 3-8 reps per set and finishing 3-5 reps short of failure are advised, as training to failure can be overly demanding and hinder recovery.
