The Best Rep Range for Big Musclesby Kourtney Thomas
There’s a lot of bro-science (or anecdotal trial-and-error) in the realm of hypertrophy training. And no matter what any of us gym rats want to admit, we have all participated in it at some point or another. Because, while a lot of the time bro-science is largely unsubstantiated by actual science, there are instances in which the anecdotal experience of years of bodybuilding does, indeed, match up with that of the findings of scientific studies.
Score one for the bros! But I’ll get to that in a minute.
When it comes to the best repetition range for specific fitness goals involving weight training, the long-standing repetition continuum contained in most traditional and trusted textbooks was the go-to resource, for both fitness professionals and lifters. Most of these sources share a similar version of this scale that looks something like: 1 to 5 reps for pure strength and/or power, 6 to 12 reps for hypertrophy, and anything above that for muscular endurance. It has always been implied that, having a specific goal in mind, crossing between those rep ranges for your training would be pretty much flat-out worthless — as in, you could never get strong if you only train in the 8- to 10-rep range, or you could never get big if you only train sets of 3 or sets of 15.
Particularly pertaining to the best repetition ranges for hypertrophy, there wasn’t much scientific research to support these claims for quite some time; it was limited, at best. We could go back to the late 1800s and a sample exercise routine of Eugen Sandow, considered the father of modern bodybuilding, and see that he trained in the 6- to 12-repetition range. (And also, often in a loincloth. Google it.)
We can head into the 1940s, taking a look at Steve Reeves’ routine, which was largely in the 8- to 12-rep range — he was considered the greatest bodybuilder of the pre-steroid era. Moving into the 1960s, Larry Scott, the very first Mr. Olympia, trained firmly in the hypertrophy range at 8 to 10 reps.
Stepping into the realm of more current and familiar faces, Arnold Schwarzenegger, Dorian Yates, and Ronnie Coleman all trained well within the hypertrophy range, too.
Some of the most popular female bodybuilders of the 1980s erred more to the high side of the range, but certainly didn’t neglect moderate-rep training. More recent female Ms. Olympia winners, Iris Kyle and Lenda Murray, were in the same camp, doing much of their quality work in the 8-to-12-rep range.
Certainly we know there’s something to this hypertrophy range. But do we really know? Thanks in large part to Brad Schoenfeld, we have a far better idea. In the late 1990s and early 2000s, Schoenfeld began exploring the wide-open domain of how best to lift for gains, backed by science. The results of his studies, and his analyses of many others, were pioneering, and the information we have learned from his work has shaped hypertrophy programming in the modern age.
Schoenfeld’s 2010 paper, “The Mechanisms of Muscle Hypertrophy and Their Application to Resistance Training,” published in the Journal of Strength and Conditioning Research, was groundbreaking. This paper reviewed the literature and drew conclusions about the three most important mechanisms for muscle hypertrophy. Also included were the training variables that affect these mechanisms, with intensity (ie: load) being one of them.
Schoenfeld’s findings regarding intensity (i.e., how heavy the weight is) determined that it has a significant impact on hypertrophy, and is arguably the most important variable for stimulating growth. That certainly makes the question of “the perfect rep range for hypertrophy” a valid one to discuss. As expected though, the results were in line with the hunches, and a repetition range of 6 to 12 reps per set was determined to be optimal for maximum muscle gains.
All those women and men mentioned above? Validated.
Well, in part, anyway. But not all were left convinced, including the researchers. And the door had been opened, so Schoenfeld, now widely regarded as one of the leading authorities on hypertrophy, continued delving into the topic in his research. He has published over 100 peer-reviewed research articles, as well as several textbooks, and since 2010, has come up with some further interesting findings about the hypertrophy loading zone.
In 2014, Schoenfeld’s study “Effects of different volume-equated resistance training loading strategies on muscular adaptations in well-trained men” was published in the Journal of Strength and Conditioning Research. Essentially, this study compared bodybuilding-style training and powerlifting-style training, based on how these kinds of lifters actually perform their training, holding volume-load equal. The findings boiled down to the fact that similar hypertrophic gains could be achieved with each style of training, and a combination of both heavy and moderate load training is a great approach. However, it was noted that, from a practicality standpoint, it is applicable, and more efficient, to work within the hypertrophy range to allow for performance at the same volume-load without overtaxing the body’s systems. Basically, that means that for most everyday lifters, doing quality work in the hypertrophy range will provide you with the same gains as a low-rep range, and the least amount of burnout or risk for overtraining.
Also observed in this study was that this applied to global hypertrophy of the whole muscle, and different rep ranges targeted different muscle fiber types to a higher degree. Thus, combining moderate-rep training with some lower-rep training (to increase strength that eventually allows use of heavier loads during moderate-rep training) with some higher-rep training (to increase muscular endurance for those times when you want to perform added reps at a moderate load) would provide the best overall result.
In December 2016 was another Schoenfeld study comparing similar training protocols — 2- to 4-repetition heavy-loading range and an 8- to 12-repetition moderate-loading range — but this time, with sets being equal between the two. The evidence suggested that, as one might expect, the heavier load training did produce greater strength gains, but again, moderate load, moderate-rep training produced greater hypertrophic gains than the low-rep training. Interestingly, that supports the traditional repetition continuum, but also reveals that higher volume becomes more important for maximizing muscle gains.
Certainly, Brad Schoenfeld is not the only researcher out there taking an interest in the best rep range for hypertrophy; in his book Science and Development of Muscle Hypertrophy, he delves into the research studies of many other authors and summarizes those findings. The “References” section includes a staggering 861 separate studies! Not all of them are specific to rep ranges, of course, but the data from multiple sources relevant to the topic included in this book supports much of what I’ve already mentioned above.
Stronger By Science, a website run by Greg Nuckols, also does a great job of rounding up, reviewing, and interpreting the best research out there. In an article published early 2016 and updated September 16, Nuckols investigated this same topic through a multitude of studies from different sources. In several of the studies available, comparing training in different loading zones resulted in very similar gains — many of the differences between the loading ranges were not statistically significant. And based on these available studies, he interestingly concluded that the hypertrophy range essentially doesn’t exist. While there is merit to working within the 6- to 12-rep range simply because it is the range that allows most people to work the hardest, the most frequently, with the best recovery, it’s not necessarily the end-all when it comes to muscle gains and could involve some individual variability.
Teasing out the finer points from all the scientific evidence we currently have on the topic, it can be inferred that, undoubtedly, everything works when it comes to hypertrophy. There is most definitely value in training across a wide range of repetitions, and in order to truly encourage the best overall picture of strength, size, and fitness, you should incorporate training in all rep ranges across the continuum, not neglecting low- or high-rep training for only moderate-rep training. But if your main focus is on maximum muscle gains, it is to your advantage in many ways to spend the majority of your time training in the hypertrophy range.
I lean a little more toward experience and broscience (hey, if it works, it works!), but I do keep an ear to the ground for new findings. So on the topic of ideal rep ranges for hypertrophy? My favorite answer flows from both the vast body of knowledge from experienced bodybuilder types and the science: Moderate reps (6 to 12) and loading provide maximal gains for most.
Do you secretly want arms as big as your life? Or, if that’s an overstatement, ready to really look like you lift weights? And have people go, “Oh my god your arms look so strong!” (If you’re not into that, go ahead and skip this free downloadable.)
If more muscular arms are something you’d like to embrace, input your email address here to get your FREE copy of Kourtney Thomas’s “Arm Pump”: a detailed, easily implementable tip list and three-workout arm plan that you can do in any combination to pop your shoulders and round your biceps. Each exercise in the plan is demonstrated and explained clearly through photos and thorough written instruction.