Do high reps build more muscle than low reps? This is the first hot topic up for discussion in this upcoming series of roundtables where I bring together the brightest minds in nutrition and weight training science.

Besides the original four horsemen, that is yours truly, Lyle McDonald, Alan Aragon and Borge Fagerli, I have invited James Krieger to the table.

Lyle and Alan hardly need any introduction but what about these other cats?

James Krieger has a very impressive set of credentials and his input today will be very valuable due to his experience as a published scientist. He’s done a great deal of research and published several peer-reviewed articles on weight training. Most known among these is his extensive research on single vs multiple sets of resistance exercise for muscle hypertrophy.

Some of you might not be familiar with Borge but that’s just because I, Lyle and Alan prefer to keep him a secret and use him for fun and profit. Just kidding… Borge is the CEO of MyRevolution, a Norwegian supplement company and fitness community. He is also a respected fitness and bodybuilding coach with a tremendous amount of real world experience and many interesting ideas. If you’re looking for a new and effective way to approach weight training, check out his Myo-reps protocol.

Today we’ll discuss a study that has been causing quite a stir in the fitness and bodybuilding community since it was published two weeks ago.

Read the free full text version here: Low-Load High Volume Resistance Exercise Stimulates Muscle Protein Synthesis More Than High-Load Low Volume Resistance Exercise in Young Men

My reflections and summary of the study, and questions to the attendees, follows below.


Intro

A recent study showed that 4 sets of leg extensions to failure at 30% 1RM was superior to 4 sets to failure at 90% 1RM.

In practical terms, this seems to suggest that you’d get more muscle growth from squatting with 120 lbs for high reps than squatting with 360 lbs for low reps if your 1RM squat is 400 lbs.

This was not a perfect study by any means. For example, there was a tremendous gap in terms of work volume between the 30% and the 90% group (96 reps vs 20 reps). It would also have been more interesting to see a middle group in the 75-85% range (6-10 reps), rather than only comparing extremes.

Still, I think the results came as a surprise to many, including me. Various theories and explanations for the results has been voiced, such as the lower body being more responsive to higher reps, as well as problems with the study methodology itself (sample size being too small).

Nevertheless, at a first glance this study seems to suggest that the “pump ‘n’ tone”-routines we so often poke fun at are more effective than lower reps – at least when it comes to leg training.

Anecdotally, I’ve actually had my best results from leg training with 20-rep breathing squats. However, breathing squats are a different animal in the sense that you are not performing reps in a continuous motion. Rather it basically ends up being a rest-pause protocol with your 10-12RM weight. Not quite the same as working with your 30% 1RM weight. In recent years, I have shied away from high rep leg training since I require a long time to recover from it. The DOMS is infernal and going over 15 reps on lower body movements is an overall unpleasant experience.

Questions

  1. Given the issues with this study, do you think the author’s conclusion, that high rep leg training is more effective than low rep leg training, may be right?
  2. What are your own experiences regarding leg training? Do you think that legs should be trained in a different fashion than the upper body for optimal muscle growth? This study looked at leg extensions, which target the quads. How about glutes, calves and hamstrings?

James Krieger

Picture of James Krieger
  1. I don’t think the authors can make such a broad conclusion, given the study design. The only conclusion that can be drawn is that 4 sets of failure at 30% 1RM stimulates more protein synthesis than 4 sets of failure at 90% 1RM. This result doesn’t surprise me given the much greater volume of work in the 30% 1RM group.

I know Stu Phillips personally and worked with him on a protein advisory committee. He does very good work, but I’m surprised they did this study in the way they did. Kumar et al (2008) already have a study like this, and it was better in the sense that they kept the volume load equal between conditions. They also did leg extensions, and they found an increasing protein synthesis response as you went from 20% 1RM to 60% 1RM, with no further increase beyond that.

However, when you look at Kumar’s data, the young subjects showed a trend for increases up to 75% 1RM until a plateau was finally reached; I think the lack of significance in the 60-75% range was more an issue of statistical power. So that data would indicate that the middle range that is so popular likely is optimal for hypertrophy.

Another problem with this particular paper is they only looked at protein synthesis. However, hypertrophy is the result of protein synthesis exceeding protein degradation. Really you need to look at net protein accretion and not just the synthesis response in isolation. Without protein degradation data it’s really hard to say which one did better.

I think this paper does indicate that there is value to “light” days, and you can obviously stimulate protein synthesis even if you’re not using heavy weights. I think too many people are caught up in the notion that every work out must be heavy to get benefit out of it.

  1. In terms of legs, there certainly is a lot of anecdotal evidence that people tend to do better with slightly higher repetitions and volumes for the legs. However, I don’t know if anyone has truly put this to the test experimentally. Intuitively, it makes sense…since you’re walking around on your legs all day, it takes a bigger stimulus to the system to see an increase in protein synthesis. Like you, Martin, I’ve tended to do better with legs in the 10-12 rep range while better with upper body in the 6-10 range.

Borge Fagerli

  1. There are a few caveats with this study. The first and most obvious one is that it was a short-term study only looking at markers for protein synthesis, to conclude anything at all you would need a longer-term study showing actual muscle accretion. There are studies showing how endurance training can lead to rebound MPS (muscle protein synthesis or myofibrillar protein synthesis), but you don’t really see any crazy hypertrophy in these protocols over time, do you?

Another one is the mode of exercise. Leg extensions are quite a different animal than e.g. squats or leg presses and I would like to see someone surviving 4 true sets to muscular failure with squats at 30% of 1RM.

With leg extensions, you can keep constant tension on the muscle, and thus reach a hypoxic state from the occlusion effect. We know that the occlusion effect leads to higher fiber recruitment and more metabolic/oxidative stress. So you really have to look at ‘effective’ reps in this protocol.

The first reps of the first set are essentially just work needed to reach this state of higher recruitment, the latter sets will reach higher recruitment levels earlier. This is exactly what my Myo-reps protocol is based on, and you would probably need do a lot less total reps to achieve the same effect, if the rest periods between sets were 10-20 seconds instead of 3 minutes. The 30%FAIL condition probably ended up around 50-70 ‘effective’ reps, whereas all 20 reps in the 90% group were ‘effective’ from a recruitment point of view.

All in all, the study shows that there is value in metabolic type training, but with the lack of actual long-term measurements of hypertrophy, I wouldn’t disregard the heavy stuff we all know works for getting big and strong. And remember the Goto et al study where the combination group of heavy + light had even better results than the heavy or light group. So do both.

  1. Yes and no. You still need heavy progressive loading with sufficient volume and frequency to get a muscle to grow. The problem with legs is that it’s painful to push yourself closer to failure, and most people (yes, me too) will usually chicken out just when it begins to hurt, way before hitting true failure. And be rewarded with chicken legs for the effort.

For safety reasons, I wouldn’t want people to get stuck with their knees behind their ears in the bottom position of a leg press or at the bottom of a squat with their spines sticking out of their back, either.

So while you can argue that legs probably need more work since you walk around on them all day, it’s also a matter of doing more reps and sets to compensate for the inability to get enough ‘effective’ or ‘quality’ reps in any given set.

Alan Aragon

Picture of Alan Aragon
  1. I’ll echo Borge’s mentioning that this was an acute study whose long-term effects are strictly speculative. Additionally, I’m baffled about the load intensities the authors chose to compare (30% vs. 90% of 1RM), especially for the purpose of investigating what might ultimately be better for hypertrophy (as opposed to performance measures like strength or endurance).

A detailed literature review by Wernbom et al suggested that 60-85% of 1RM tends to be the most effective at causing hypertrophy [1]. Specifically for the quads, they found the highest rates of hypertrophy occurred at intensities over 60% of 1RM. Importantly, this review examined the results of research lasting well beyond the acute phase, where measuring changes in muscular cross-sectional area are possible.

This conflict of data makes the present study’s short-term outcomes highly questionable. In principle, this reminds me of an acute study by Deldicue et al, who found that fasted training increased molecular markers of anabolism to a greater extent than training in a fed state [2]. While this data is interesting, we just can’t firmly conclude anything concrete from it. It’s still speculative whether or not these were merely compensatory responses to a suboptimal protocol.

  1. This varies with the individual, but I’ve found that it’s best to go with a combination of what’s been seen to work in the field as well as the research, taking sets to fatigue at roughly 6-12 reps (although Wernbom et al suggest 8-10 is best for the quads, which is appx 60-85% 1RM). As long as an uptrend in strength (increases in reps and/or load) is maintained over time in this range, hypertrophy will occur.

Bodybuilders have traditionally stuck to higher rep ranges for quads, regularly going into the teens. However, I think the increases in mass are far more attributable to progressive overload with sufficient total volume rather than the rep range per se.

For building hamstring and glute mass, I haven’t personally experimented with reps outside of conventional ranges. For calves, I hate to sound fatalistic, but think that it’s a matter of having picked the right parents. This is not to say that calves are impossible to bring up if they happen to suck; it’s just that in my observations, people predisposed to crappy calves tend to struggle equally regardless of the load intensity imposed.

  1. Wernbom M, et al. The influence of frequency, intensity, volume and mode of strength training on whole muscle cross-sectional area in humans. Sports Med. 2007;37(3):225-64.
  2. Deldicue L, et al. Increased p70(s6k) phosphorylation during intake of a protein-carbohydrate drink following resistance exercise in the fasted state. Eur J Appl Physiol. 2009 Nov 18.

Lyle McDonald

Picture of Lyle McDonald
  1. Well, after Blade and Alan’s comments, I don’t really have much to add to the topic. I too would have liked to have seen an intermediate intensity group (either matched or not matched for volume, possibly both). Certainly other work (e.g. the Wernbom review that Alan referenced) suggests that intermediate intensities are probably better than either extreme.

As well, with an acute study like this, it’s hard to say what the long-term results would be in terms of growth. I agree that it is at least interesting given the bias most have towards heavier work for hypertrophy.

  1. Empirically, many do seem to think that legs (or at least quads) respond better to higher reps. I have to think that part of this may be biomechanical especially in terms of squats. For some people, heavy low-rep squats turn into a pseudo good morning meaning that it’s mainly low back stress and/or more stress thrown onto the glutes and hamstrings. For those people, higher reps allow a more upright torso meaning the opposite: less low back stress and more thrown onto the quads.

In keeping with that, Olympic lifters (for whom high reps in squats are 5) usually have pretty decent sized legs; of course most of them are also built to squat (and squat high bar).

Beyond that, like Alan, I can’t say I’ve ever paid much attention to training glutes or hamstrings differentially to quads, typically using some mix of lower rep work (5-8, sometimes lower) for heavy compounds and following it up with additional higher rep work (10-12 or more) on more isolation work.

I do agree that 20 rep squats can be amazing but as you point out, it’s more of a heavy rest-pause approach than what was being described in the paper in question.


Summary

  1. 4 sets to failure at 30% 1RM increases protein synthesis more than 4 sets to failure at 90% 1RM. This is not surprising given the much greater training volume in the 30% 1RM group. The 30% 1RM group almost did five times as many reps as the 90% 1RM.

However, as everyone was quick to point out, only looking at protein synthesis does not tell the full story. A better marker for muscle growth would be protein balance/accretion (protein synthesis – protein breakdown), but in this study protein breakdown was not measured.

  1. Other studies clearly show that a higher load is more effective in terms of increasing protein synthesis. James mentioned a study* which looked at intensities ranging from 20%-90% 1RM (i.e. 27 reps to 5 reps), suggesting the 75% 1RM load provided maximum MPS with no further increase beyond that.

* Read the free full text version here: “Age-related differences in the dose–response relationship of muscle protein synthesis to resistance exercise in young and old men”

  1. It’s very important to think long term and not get focused on the short term. It’s also important to consider the “downstream effects” of every training session.

For example, consider squats using German Volume Training (10 x 10 at 60% 1RM, 1x/week) vs Starting Strength (3 x 5 at 82-84% 1RM, 2-3x/week).

Lots of people have had success with the latter, very few with the former.

Even if a GVT squatting session increases protein synthesis more than a SS squatting session, there is no way you can do a GVT squatting session more than once a week. The absurd volume (100 reps is actually very close to the study we just discussed where subjects did 96 total reps) would also lead to whole body fatigue, predispose towards overtraining, hellish DOMS and negatively affect other lower body movements such as deadlifts.

Due to the crippling effect of GVT, properly cycled SS with 2-3x/week squatting wins out in the long-term; greater frequency and less negative downstream effects make up for a lower short term protein synthesis.

  1. As a closing point, while this was an interesting study, the majority of the evidence still points to intermediate rep ranges being optimal for muscle growth.
  2. As for our personal experiences, no one outright claimed greater results with either low reps or high reps exclusively. If anything, there was a tendency to favor intermediate rep ranges or using low(er) and high(er) reps in combination.

Highlights and take away lessons

  • James: “I think this paper does indicate that there is value to “light” days, and you can obviously stimulate protein synthesis even if you’re not using heavy weights. I think too many people are caught up in the notion that every work out must be heavy to get benefit out of it.

Good point which goes in line with my own experiments with high frequency training.

  • Borge: “The problem with legs is that it’s painful to push yourself closer to failure, and most people (yes, me too) will usually chicken out just when it begins to hurt, way before hitting true failure”.

Very true. I can count the people I’ve seen squatting close to their limit in the 10 rep+ range on…two fingers.

  • Alan: “In principle, this reminds me of an acute study by Deldicue et al, who found that fasted training increased molecular markers of anabolism to a greater extent than training in a fed state [2]. While this data is interesting, we just can’t firmly conclude anything concrete from it.”

Alan points out that acute response does not predict long-term results. I’ve actually written an article about the study Alan mentions. Read: “Fasted Training Boosts Muscle Growth?”

  • Lyle: “For some people, heavy low-rep squats turn into a pseudo good morning meaning that it’s mainly low back stress and/or more stress thrown onto the glutes and hamstrings. For those people, higher reps allow a more upright torso meaning the opposite: less low back stress and more thrown onto the quads.”

Great point by Lyle. Some people just aren’t made for squatting and are better off using the leg press as their main leg movement. Check out Lyle’s article on this topic: “Squat vs Leg Press for Big Legs”.


Hope you enjoyed and learned something new from this roundtable. There will be more in the future.

Check out some other roundtables I’ve participated in:

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