The Basis of Hypertrophy
The Question
Every individual looking to jumpstart their fitness career seeking the goal of gaining muscle, or hypertrophy, searches high and low for the optimal number of sets and repetitions to perform.
I remember my high school gym coach instructed us guys to lift heavy weight (80% of our one-rep-max) for extremely low reps (3-5 repetitions) with minimal rest time (30 seconds - 1 minute). I frequently hear "broscience" tossed around in the gym about how you should train in the repetition range of 6-12 with only 30 seconds of rest. I will do my best to logically and concisely give my audience the proper scientific information in order to properly deduce what that range is.
Sets
Generally speaking, the more sets you perform for a given exercise, the more advantageous in terms of hypertrophy. What does this mean? The entire mechanism of gaining muscle revolves around increasing the volume of your training bout. This means optimizing the number of sets, reps, and the weight you use. Therefore, as you perform more sets of the same exercise, more reps, and/or increase the load, your muscles will be progressively utilized and fatigued, nearing the apex of fatigue, or muscle failure (to a point).
It is known that there are elevated increases in protein presence and similar anabolic pathways following multiple sets of an exercise versus merely just one. Which makes obvious sense, performing one set will not be ample to provide the necessary resistance on your muscles while three sets pushes the target fibers to fatigue and promotes the needed stress for growth. In accordance, Dr. Brad Schoenfeld states that "muscle protein synthesis in a 3-set condition remained significantly elevated at 29 hours post-workout compared to a 1-set condition which returned to baseline" (Schoenfeld 52). This simply means two things: protein synthesis is elevated when you do more sets and this synthesis remains heightened even many hours after your workout. The next question is, how many sets qualify as overkill, or is there a plateau seen after "x" amount of sets?
The brief answer is yes, there is a plateau. One should aim to perform between 4-6 sets per exercise. Merely utilizing the set range between 1-3 will be inhibiting as you are neglecting the anabolic benefits that occur past 3 sets, while continually pushing your body past 6 sets risks overtraining and unnecessary stress. Consistent training in this high set range with increasingly heavy weight can also warrant injuries.
Reps
The aim for repetitions is to reside in the range whereby your muscles are experiencing optimal tension for an ideal amount of time.
When training in a low rep range (1-5 reps), generally with relatively heavier weight and more rest, the time of exercise is shorter than compared to a medium (8-12 reps) or light rep range (15+ reps). Hence, despite the extreme intensity from the heavy load, the duration of the actual exercise is fairly short and the time of tension is drastically decreased, decreasing the metabolic stress. Using a lighter rep range, the weight you use will naturally be compromised. Think about it logically, if you can only bench 225 for 1-5 reps, you cannot assume to walk into the gym and pump out 15+ reps of it without prior practice. So, inherently, when you aim to lift in this range you will be sacrificing some of the weight and although there is more time of tension, the fibers that you would recruit with the heavier weight are not being utilized.
What is the ideal rep range you ask? 8-12 reps is what you should aim for. This range is the best of both worlds - the time of tension maximizes the stress your muscle fibers undergo with a weight that is not significantly compromised and ample muscle fibers are being recruited to promote the metabolic cascade you need to build muscle.
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Standardization
Please take into account that genetics and your baseline musculature do play a role in hypertrophy and all training for that matter. What may work for one individual may not work for another. Also, your muscles are not completely uniform, meaning the fibers that contribute are in fact different and are activated using a range of stimuli. It is important to attempt various training routines in search of what works best for you while conducting independent research of your own.
Thank you immensely for the read. If you wish to constructively critique or compliment the post please do so. All feedback is welcome.
Finally, I genuinely enjoy blogging about fitness and the mechanisms of exercise, if any of you wish to chat or create a sub-community centered around fitness please comment below or email me at alexi.papakyriacou15@gmail.com.
Alexi Papakyriacou
Bibliography
Schoenfeld, Brad. “Chapter 3.” Science and Development of Muscle Hypertrophy, Human Kinetics, 2016, pp. 51–93.