The stronger the better, right? But does that hold even if your main, or even only, training goal is gaining muscle mass? That question is also the topic of the day for this article. To help us answer that question, we have a brand new study to dissect. An interesting one, to boot, with trained participants and a well-devised methodology.
Sounds interesting? Well then, let’s get into it without any further chitchat. The study in question is called Is stronger better? Influence of a strength phase followed by a hypertrophy phase on muscular adaptations in resistance-trained men, published in advance on November 26, 2020, in the Research in Sports Medicine journal.1
Light Weight, Heavy Weight – Similar Results?
Several recent studies show that you build muscle just as well doing few or many repetitions, as long as you take your sets to muscular failure. Of course, this means that training with very different loads builds muscle to the same extent. Thirty reps to failure require you to use a much lighter weight than six reps to failure. If you go heavy enough to fail between 1 to 4 reps, however, you gain more strength than muscle mass.
At the same time, research shows that if you match sets x reps x load, you get stronger and gain more muscle training heavy than light. Progressive overload is one of the most fundamental training principles, not only to get stronger but to gain muscle effectively as well.
Mechanical tension in the muscle you’re training is important if you want to stimulate growth. The greater stress you put on a muscle fiber, the greater the signals for hypertrophy you send to it.
Since using a heavier weight puts more stress on your muscle fibers, it’s only logical to assume that you gain more than strength by getting stronger, even if your main goal is hypertrophy. You can use heavier weights in your hypertrophy-specific training, stress your muscle fibers more, and boom! You have a greater potential for muscle growth.
The New Study
With that reasoning in mind, researchers from Brazil and the US conducted a study to test the theory. They randomized trained men into two groups, one of which only engaged in hypertrophy-specific training for eight weeks. The other group started their eight-week-long training period with three weeks of heavy strength training, after which they switched to the same program as the hypertrophy group for five weeks.
Afterward, the researchers measured which of the groups gained more strength and muscle mass.
A simple but elegant concept. Let’s take a closer look at it.
Meet the Participants
The researchers recruited 38 trained men between 21 and 27 years of age. On average, they had spent 4–5 in the gym and were capable of squatting at least 1.5 times their body weight in kilograms. Decently strong and physically fit subjects, in other words. All of them were healthy without any illnesses or medical conditions.
During the study, 12 of the men withdrew due to personal reasons unrelated to the study. In the end, 26 participants completed the entire training program and all the procedures surrounding the study.
The Design of the Study
The study kicked off with three weeks of preparatory training. During that time, all participants completed the same exercise regimen: two lower body workouts per week, consisting of the squat and the leg press. They performed 4 sets per workout and 8–12 reps per set. They worked out unsupervised during the preparatory period, which was intended for the researchers to standardize the training volume.
After three weeks of squatting and leg pressing, the researchers measured the participants’ thigh muscle thickness using ultrasound. They also assessed their 1RM in the squat and the leg press. The ultrasound measurements took place at least 72 hours after the last workout of the preparation period. This practice allows any swelling from the training to go away, so as not to mess with the results of the ultrasound.
The participants tested their 1RM in the squat and the leg press three times during the study. Once after the preparatory period but before the actual study, three weeks into the study, and once after the last training session. Following a warm-up consisting of 1 set of 8 reps using approximately 50% of 1RM and 1 set of 3 reps using approximately 70% of 1RM, the testing protocol allowed the subjects five tries to reach their real 1RM. The researchers calculated the warm-up weights based on the recorded loads the participants used during the preparation period.
After the testing and measuring, the subjects were randomized into one of two groups. The first group spent the following eight weeks of training for hypertrophy. The other group started off their eight weeks with three weeks of really heavy training focused on gaining as much strength as possible. After that, they switched to the same hypertrophy-specific training as the first group.
The Training Programs
The training programs the participants followed for eight weeks were simple and straightforward. We’re talking two lower body exercises, the squat and the leg press, in that order, twice a week. The same exercises as during the preparatory training, in other words.
The hypertrophy group performed 4 sets per exercise, 8–12 reps per set, for the whole 8 weeks. In between sets, they rested a single minute.
The combined strength- and hypertrophy group followed the same program, except for the first 3 weeks, when they used heavier weights that only allowed 1–3 reps per set. After that back-breakingly heavy start, they switched to the same training program as the hypertrophy group for the remaining 5 weeks.
Over to the most interesting part, the results!
In total, the men in the hypertrophy group lifted more than the combined group, both in the squat and the leg press, over the eight weeks of the study. They squatted a total of 46,809 kilograms and leg pressed a total of 146,659 kilograms, on average. In comparison, the total amount of weight lifted by the group combining strength- and hypertrophy training amounted to 36,589 and 109,330 kilograms, on average, in the squat and the leg press.
At baseline, after the preparation but before the actual study, there were no differences in 1RM-strength or muscle thickness between the groups.
After eight weeks of lifting, however, the researchers discovered that both training protocols were not equal.
The group combining strength- and hypertrophy training had pulled ahead. They gained more muscle mass and increased their 1RM more in both exercises.
The subjects who had focused solely on hypertrophy, using lighter weights and more reps during the entire eight weeks, also increased their muscle thickness, but not as much.
Perhaps the most interesting thing happened on the way to the final results, though. After the first three weeks of training, the group training solely for hypertrophy had gained the most. Their muscle thickness had, at this time, increased by 2.6%, on average. The other group, focusing on gaining strength at that point, had barely gained anything. However, once that group switched over to hypertrophy-oriented training, they started gaining much faster, overtaking the hypertrophy group and ending up with 40% greater gains!
There we go! A fairly simple but well-designed study. Both groups increased their strength and muscle thickness after 8 weeks of training. The participants who aimed for max strength gains before switching to hypertrophy-oriented training gained more than those who just focused on hypertrophy, even though they trained for hypertrophy for a shorter period.
Interestingly enough, the victorious group completed the study with a lower total training load. We know for a fact that training volume is an important factor when it comes to hypertrophy. Still, the participants who lifted heavier and increased their strength more also gained more muscle mass, even with a lower training volume.
If you use a heavier load in repetition intervals intended for hypertrophy (say, 6 to 30 reps), you place greater mechanical stress on your muscles and activate them more. This applies mostly to type 2 muscle fibers, the ones with the greatest growth potential.
If you get stronger, you can use heavier weights in your hypertrophy-oriented training. This practice creates greater tension in your muscles and stresses them more, stimulating more muscle growth. In other words, gaining strength helps you gain muscle as well.
Should You Separate or Combine Training for Strength and Hypertrophy?
These results raise an interesting question. Do you need to separate your strength-focused training from your hypertrophy-focused training as they did in the study?
I’m not so sure about that.
No controlled studies confirm or deny this, but experience tells me that combining exercises using heavy sets and few reps for strength and higher reps using lighter weights for hypertrophy in the same workout works just fine.
For example, you could place heavy, low-rep squats, deadlifts, and bench presses at the start of your training sessions, switching to more hypertrophy-specific training as your workouts progress. Strength and muscle mass go hand in hand, and I see no reason why you’d have to separate your training into specific blocks. Unless you want to, of course.
Will you gain as much muscle mass by training for both strength and hypertrophy at the same time as by splitting the protocols like in this study? Unclear. But it does work.
Also, this study only looked at the effects of lower body training on strength and muscle thickness of the participants’ thighs. However, I don’t know why the same principles wouldn’t hold for the upper body as well.
What About the Diet?
The researchers did not control what the participants ate in any way. That might be a limitation. At the same time, another recent study demonstrates that self-reported diet and eating habits do not differ significantly between low-responders and high-responders to strength training.2
The kind of training you enjoy the most and can keep up over time probably also gives you the best gains. As usual. However, don’t ignore your strength even if getting stronger isn’t a goal of yours in and of itself. Even if that goal is spelled “hypertrophy”, getting stronger improves your chances of gaining muscle mass as well.
- Res Sports Med. 2020 Nov 26;1-11. Is stronger better? Influence of a strength phase followed by a hypertrophy phase on muscular adaptations in resistance-trained men.
- Front Physiol. 2018; 9: 834. Physiological Differences Between Low Versus High Skeletal Muscle Hypertrophic Responders to Resistance Exercise Training: Current Perspectives and Future Research Directions.