The best rep range for muscle growth is the key component of bodybuilding training. You might think you know, but this is continuously investigated. We check out the accepted wisdom and how it holds up to the latest research. Too many, too few, or just right—what’s the ideal number of reps per set to maximize growth?
TRADITIONAL BEST REP RANGE: MEDIUM
Historically, the medium rep range of 8–12 has been considered optimal for muscle growth. This range balances mechanical tension (from a moderately heavy weight) and metabolic stress (from moderately high reps), providing what most believe is the sweet spot for hypertrophy. Training within this range typically involves moderate weights (60%–80% of one-repetition maximum) and rest periods of 60–90 seconds.
Benefits of the 8–12 Rep Range
Efficient muscle stimulation: Combines strength and endurance elements.
Time-effective: Allows for multiple sets within a reasonable timeframe.
Joint-friendly: Moderate weights reduce stress on joints compared to heavier loads.
NEW BEST REP RANGE
Recent research suggests that muscle growth can occur maximally across a broader rep range, extending the medium range from 8-12 to a broader range of 3-30 reps per set, provided all such sets are performed close to failure.
Exercise scientist Dr. Brad Schoenfeld, PhD, recently expanded on a meta-review of all the recent research on this topic. He wrote:
For hypertrophy, the overwhelming body of evidence indicates that whole muscle hypertrophy is similar regardless of load with repetition zones ranging from 3 to at least 30, providing training is carried out with a high degree of effort. Evidence remains unclear if there may be fiber type-specific advantages to different loading zones (i.e., possibly a greater type 1 response in light load and greater type 2 response in heavy load); if such a difference does exist, the effects would be modest.
Key Insights on the Broader Rep Range
High-rep training: Using lighter weights for 13–20 reps can still induce hypertrophy if sets are performed to near failure.
Low-rep training: Heavier weights with 4–6 reps can also promote muscle growth, especially when combined with higher-rep sets.
Variety matters: Incorporating different rep ranges can target various muscle fibers and prevent growth plateaus.
THE ROLE OF TRAINING TO FAILURE
Training to failure involves performing reps until no further repetitions are possible with proper form. You know this because, despite your maximum effort, you’re unable to complete the last rep. While this method can maximize muscle fiber recruitment, it’s not necessary for growth. Exercise science shows that maximum effort is the key. You need to come close to failure on working sets, but you don’t need to fail to eke out that last rep to maximize growth. Consider pushing some sets to failure but stopping just short on others to balance intensity and recovery.
How does this relate to optimum reps-per-set? If you only do, say, three reps with a very heavy weight it will be much harder to eke out a fourth rep than if you did, say, 15 reps. This is why sometimes training heavy works against training hard. On the other hand, if you do, say 35 reps, it’s difficult to push yourself to the limit or near the limit. You’re recovering intra-set so you’re able with relative ease to get rep 36 and rep 37 and on and on.
Too few makes it too hard to approach failure; too many makes it too easy. That’s why there’s still a rep sweet spot. It’s just wider than 8-12. You’re probably find that 6-20 is best for most sets if your goal is maximizing size. Still, sometimes you’ll want to test your strength and go lower and sometimes you’ll want to do a final blow-out set and go higher, and not only is that okay but the variety will probably work to your advantage.
PRACTICAL RECOMMENDATIONS FOR MUSCLE GROWTH
Incorporate a Broad Rep Range: Utilize 6–20 reps per set, adjusting based on the exercise and individual response.
Use Maximum Effort: Push sets to failure or near failure.
Focus on Progressive Overload: Increase weight, reps, or sets over time to continually challenge muscles.
Balance Intensity and Volume: Combine heavier, low-rep sets with lighter, high-rep sets to target different muscle fibers.
Prioritize Recovery: Ensure adequate rest between workouts, proper nutrition, and sufficient sleep to support muscle repair and growth.
Listen to Your Body: Adjust training variables based on individual progress, fatigue levels, and overall well-being.
BEST REP RANGE FOR MUSCLE GROWTH: CONCLUSION
While the medium 8–12 rep range has long been associated with muscle growth, evidence supports a broader spectrum of effective rep ranges. Keep most sets in the 6-20 range, though even this can be expanded on occasion.
