As trainer to the multi-time World’s Strongest Man, Hafþór Júlíus Björnsson, Sebastian Oreb, who is also known as the “Australian Strength Coach” knows how to get epic results from his clients. So, when he decided to weigh-in on the long-running debate concerning which rep range is best for reaching hypertrophy, the astute Aussie gave a superlative take. Here’s what you need to consider.
The most reliable rep range for reaching the muscle building state known as hypertrophy is a subject that is often contested among trainers and fitness influencers. Some gymgoers stick avidly to the 8-to-12-rep range no matter what exercise they are doing, while others say that going heavier with less reps is more efficient, since the process is all about reaching failure and tearing those muscle fibers so that they build back bigger. The truth, says Oreb, is that our rep range should be guided by the exercise, and not the other way around.
“Traditionally, we’ve been told that the best rep range for muscle growth is 8 to 12 reps per set,” he explains in a recent Instagram post shared with his 350,000-plus followers. “Less reps are better for strength, and more reps are better for muscular endurance, but in 2017, Dr Brad Schoenfeld, one of the best academics in the field of hypertrophy, conducted a study that found anywhere between 5 and 30 reps had equal muscle-building potential as long as you push each set close to failure. This is hugely helpful information because it teaches us that taking movements to failure is more important for building muscle than the exact number of reps that we do.”
Why the 8-to-12-Rep Range Is a Must for Hypertrophy
“So, when we are in the mood for lifting heavier weight and testing our strength, it still has great muscle building effect (despite fewer reps),” says Oreb. “Conversely, when we’re not in the mood to go heavy, we can switch to a lighter load with more reps and still have a productive muscle-building session. But here’s what the study doesn’t tell us: For an exercise to be effective for muscle building, the specific muscle that we’re trying to build needs to be the limiting factor of the exercise. Or, in other words, the muscle that we want to grow must be the one that fatigues first, and the reason that we can’t do more reps.”
Oreb explains that if you take squats as an example, the extreme of 30 reps wouldn’t work here, because the effect it would have on the back, or even our cardio output, would take the focus away from the target muscles such as the quads before reaching the full 30 reps.
“On the flip side, how do you feel after doing isolation exercises like calf raises or dumbbell lateral raises for sets of 5 reps for failure? It just doesn’t make sense. We need to understand that different exercises come with difference complexities. Although this research is so valuable, it doesn’t debunk the idea that the optimal rep range for hypertrophy is 8 to 12 reps. Most exercises feel effective within this range and there’s a reason most top bodybuilders spend most of their time within the 8-to-12-rep range.
The takeaway message? “Choose an exercise and pair it with the appropriate rep range to ensure that the muscles that you’re targeting is the limiting factor of the movement,” explains Oreb. “Know that muscle building is possible anywhere between 5 to 30 reps, but use your judgement to determine the right loads and reps to take that target muscle to failure. If the 8-to-12-rep range feels like it ticks all of these boxes, it’s no coincidence.”
