by Christian Thibaudeau
The Truth About Bodybuilding Reps
As long as you're training to near failure, all rep ranges are the same for muscle growth. Popular idea, but is it true? Answers here.
Rep Ranges: Don’t Keep It Simple?
To become a popular strength coach or “fitness personality,” it helps to say things people like to hear.
When I started out as both a coach and author, I craved new methods and revolutionary approaches. Innovators that broke the mold were the most popular sources of info. We’d get excited about learning the new method. We wanted to know more about why and how it worked. This led to the development of even more novel methods.
And yeah, it also led to complex programs and created some confusion about how to put all of that info together into an effective plan. But that was part of the fun. Heck, it was the most fun part!
Today, the pendulum has swung the other way. People want simple – easy to apply and easy to understand. They want REASSURING. There’s nothing wrong with that… until simple becomes “too simple.” A lot of pieces are dropped for the sake of simplicity.
The problem? This often leads to beige (a French expression that loosely translates to bland or tasteless) programs that might be simple but are very unmotivating. And, in some cases, “too simple” actually leads to faulty information.
One such example? The current trend of saying this:
“Every rep range will trigger the same amount of hypertrophy provided that you do your set with the same level of effort (proximity to failure).”
In other words, if you do 6, 12, 20, or 30 reps per set and stop one rep short of failure, you’ll get the exact same amount of muscle growth. But is that right?
Here are some quick thoughts:
Now let’s dive into the details.
How It Started
To the best of my knowledge, the idea that all rep ranges are the same comes from a study I wrote about myself in a previous article.
Basically, a group doing 3 sets to failure (leg extension) at 30% of their 1RM had the same hypertrophy gains as a group doing 3 sets to failure at 80% (but half the strength). While interesting, don’t forget this study was conducted on beginners using a single exercise. Not really applicable to our reality.
Then came the theory of “effective reps” by Chris Beardsley. (Note that I do subscribe, in large part, to this theory.) An effective rep is a repetition in a set that combines the two key factors to stimulate growth:
- A high recruitment of the growth-prone fast-twitch fibers.
- A high level of effort to complete the rep. This means that even though you’re trying to push the weight as hard as you can, it moves slowly.
You need both for a rep to be effective at stimulating growth:
- If you move a weight explosively, you’ll recruit a lot of fast-twitch fibers, but the muscle contracts too fast to have maximum tension. So, it won’t produce much growth.
- If you go slow on purpose with a light weight, you get a lot of tension on the recruited fibers but not enough fast-twitch recruitment to be effective.
In a normal set, regardless of the number of total reps you do, only the last 5 reps (if you go 1 rep short of failure) will combine both conditions and be effective for growth. Hence the belief that the number of reps you do doesn’t matter – if you push your set hard.
But Is That True?
In theory, it is. And it’s intellectually elegant and makes training super simple. If muscle growth is all you care about, you can use any rep range and load, and they’ll work equally, provided you use the same effort level.
The modern lifter loves simplicity, but reality isn’t so black and white.
For one thing, various rep range or rep-execution styles have effects other than muscle growth – effects that might be as equally desirable as growth.
For example, if you perform 6 reps (heavy weight) 1 rep short of failure, and I do 20 reps (light weight) 1 rep short of failure, we might get a similar hypertrophy response. But you’ll gain more strength than me because lower reps with heavy weights improve neurological factors more than lighter weights for high reps.
But I will gain more resistance and maybe favor increased glycogen storage (provided that sufficient carbs are ingested) by upregulating GLUT-4 more than lower/heavier reps.
Other things:
- Lower reps with heavier weights will improve neurological factors more than higher reps, leading to more strength gains.
- Higher reps can increase muscle resistance and lactate tolerance.
- Lower reps/heavier weights can have a bigger impact on myogenic tone than higher reps (making muscles look harder even at rest).
- Higher reps can possibly upregulate intramuscular glycogen storage, making a muscle appear fuller (if you’re eating enough carbs).
- Doing the initial reps of a set (the easy ones) as explosively as possible also improves neurological factors and your capacity to produce power. This could benefit an athlete wanting more muscle mass but also more explosiveness. For example, if you do 10 reps, only the last 5-6 will be hard. If you do the first 4-5 explosively on purpose, they might not build much muscle, but they will increase power output.
- Doing the initial reps of a set slowly on purpose can help develop movement control and improve intramuscular tension and the mind-muscle connection. This can be useful for beginners or for a muscle you have a problem developing.
- If you hold the bottom position of an exercise, where the target muscle is being stretched under load, for 1-2 seconds, you can get extra growth via the stretch-induced hypertrophy pathway. And you increase muscle tension at the start of the lifting portion by reducing the stretch reflex.
- If you voluntarily use a strong rebound in the bottom of a rep, you train your peripheral nervous system to better use the stretch reflex. This is very useful for athletes requiring speed, power, and agility.
- If you perform very slow eccentrics/negatives, you increase motor cortex activation, speeding up motor learning (useful for beginners). It can also help build up your tendons and reduce the risk of injuries.
- Performing very high reps (40 or more) can, over time, increase the number of capillaries going to the muscle. This speeds up recovery and helps with endurance. (See The 100-Rep Method for Big Legs.)
- Heavier loads (lower reps) will have a stronger potentiation effect on the nervous system. Doing that type of work early in the workout helps increase performance on all subsequent exercises.
- Lighter weights with a slower speed of movement done at the beginning of a workout can help you “feel” the main muscle better when you switch to a big basic lift afterward.
So no, every repetition number/range is not equal. That’s oversimplistic and short-sighted, but it’s a good marketing strategy.
And Then There’s This Study
If all rep ranges are equal for hypertrophy (provided that the same effort level is used), then it would mean that combining more than one rep range in a workout, or a week, wouldn’t provide any added gains compared to only performing one type of rep range.
The following study (1) compared 8 weeks of training (three times per week for the lower body using squats and leg extensions) for three different protocols:
- Group 1: Heavy (low reps progressing from 82% to 94% using 3-5 reps/set
- Group 2: Light (high reps using 28-34% to muscle failure for 2-3 sets)
- Group 3: Combination of both
The group combining both rep ranges had more muscle growth than both groups utilizing only one range.
Although this is only one study, it’s still an interesting finding. It shows that there might be benefits from combining various rep ranges, even strictly for growth.
My Recommendations
- I’ve always had my best results by combining at least two rep ranges in a workout. Some of my most effective workouts (The Layer System and HSS-100) use four ranges in a workout for the same muscle.
- If you’re interested in more than just size, use various rep ranges to train qualities useful in your activity. For example, an explosive athlete will do his hypertrophy work differently (different rep ranges and execution) than an endurance athlete.
- If you want to increase strength as much as size, start with big lifts with lower reps, even in an hypertrophy phase (4-6 reps, for example) and increase the reps gradually from exercise to exercise.
- If you’re training using feeling and pump as your target, start with one exercise for higher or intermediate reps (targeting the main muscle you want to develop) at the beginning of the workout.
- If going low reps/heavy weight on an exercise prevents you from properly feeling the muscle you want to stimulate, include higher rep work with maximum tension and mind-muscle connection for that muscle. In fact, if you don’t feel the target muscle doing the work, go lighter using higher reps on that movement, too.