Hypertrophy; you hear the term bandied about constantly on Instagram, and it's likely the reason you started lifting weights in the first place, but what does it actually mean? The scientific term for 'building muscle', hypertrophy simply describes the process of tissue stimulation and repair. It's the physiology of gains.
On paper, the principle is straightforward. Lift progressively heavier weights, eat a calorie surplus, get adequate rest, and your body will build larger, stronger muscles to cope with the ever-increasing loads. To truly optimise your time in the gym, however, it's worth needling in on the training protocols behind hypertrophy.
We asked three strength and conditioning experts to talk us through the mechanisms behind hypertrophy, explain how genetics affect your gains and share the most effective workout structure for maximum muscle build.
Heed their advice to transform from ropey to ripped in double-quick time.
What Is Hypertrophy?
Hypertrophy describes the growth of muscle cells through exercise, explains strength and conditioning coach Josh Taylor, founder of Coach JT. "When we train, we create little micro tears within the muscle cells we use," he says. "The recovery process essentially rebuilds these tears to make them grow back bigger and stronger."
Here's how the stimulation-and-repair process works:
- Your muscles are made up of fibres, bound together in bundles of tissue.
- When dormant satellite cells in the fibres are activated by trauma – such as, say, three sets of squats – your immune system triggers an inflammatory response to begin repairing the damage.
- At the same time, your body releases testosterone and growth factors, a hormonal hypertrophy tag team.
- Testosterone boosts protein synthesis – the creation of the protein molecules that repair the injured tissue – while growth factors instruct satellite cells to thicken the muscle fibres.
- The result is larger muscles that can handle heavier loads, i.e. the dream.
Isn't all lifting geared towards hypertrophy, then? Not exactly. If building strength is your main goal, you'll likely focus on heavy weights and low reps. If you're training for endurance, low weights and high reps will boost your performance. The optimum reps, sets, and weight for hypertrophy falls somewhere in the middle.
What Is Hypertrophy Training?
Hypertrophy training essentially describes working out in a way that maximises muscle growth. Naturally, that means resistance training – ideally a mix of compound moves, which work multiple muscle groups at the same time (like deadlifts), and isolation exercises, which target one specific muscle group (for example, lateral raises).
"Both compound and isolation exercises are desirable for a hypertrophic response," explains strength and conditioning coach Sam Pepys. "The multi-joint exercises initiate a powerful hormonal response post-resistance training. Isolation exercises provide a means of applying more targeted volume to a muscle, namely biceps or triceps."
A handful of factors set hypertrophy training apart from other iron-clad workouts. Nail them to build on your improvements and side-step a performance plateau:
Why Volume is Important to Build Muscle
The total amount of exercise performed over a given period of time, i.e. whether you spend 20 minutes or two hours lifting. "There is compelling evidence that indicates that higher training volumes are necessary to maximise anabolism," says Pepys. "Multi-set protocols favouring high volumes of resistance training optimise the hypertrophic response."
Why Frequency is Important to Build Muscle
The number of sessions performed in a given period of time – so, the number of times a muscle is worked per week. "Split routines allow for a greater volume of work per muscle week – two or three sessions – therefore enhancing muscular adaptations," says Pepys. You can divide up your workouts by body region, movement, body part or by lift.
Why Load is Important to Build Muscle
The intensity of the lift, which is "widely considered as the most important factor in the hypertrophy response," says Pepys. However, that doesn't mean you should lift heavy 24/7. "Training across a wide range – one to 20-plus reps – is recommended to maximise all avenues of muscular development, with specific focus through the six to 12-rep range," he adds.
Why Rest is Important to Build Muscle
The time taken between sets. "Despite the commonly-accepted belief that hypertrophy-orientated routines benefit from moderate rest – 60 to 90 seconds – holding at least two minutes between multi-joint is more favourable, and 60 to 90 for isolation," says Pepys.
Genetics and Hypertrophy
"It stings a bit, but the primary factor that determines how much muscle you can build is genetics," says Dr. Jacob Wilson, founder of The Muscle PHD. "Your genetics hold the key to virtually every adaptive (gains) potential you have and, unfortunately, the only way to fix this is to go back in time and pick new parents. Good luck with that!
"However, keep in mind that you can still maximise your own genetic potential through factors like training hard, eating well, sleeping well and managing stress.
"Ultimately, people get impatient in this day and age, but it's important to understand that it can take a LONG time to build significant muscle. Most of the physiques we see on physique or bodybuilding stages took 10 to 20 years of training to build. Embrace the marathon of training and you'll max out your potential."
What Is the Difference Between Strength and Hypertrophy?
Measured by testing your one rep max (1RM), strength refers to the amount of force your muscles can exert, while hypertrophy is about the size of the muscle tissue. While the two aren't mutually exclusive – generally, a larger muscle is also a stronger muscle – hypertrophy isn't the only factor that contributes to a Herculean bench press.
"Training for strength and hypertrophy has a lot of overlap, especially in newer gym goers," explains Wilson. "However, the more advanced you get, the more specific you need to train for your goals. If you generally train the six to 12 rep range, you're probably building strength and muscle at the same time."
Long-time lifters who want to boost size and strength should add training days in the 2-5 rep range, "lifting at least 80% of your 1RM on compound movements like squats or bench press," Wilson continues. "These rep ranges are generally more effective for building strength and are also more specific to how we test strength with the 1RM assessment."
Aside from making you stronger, training for hypertrophy has numerous benefits. "If you put the pieces together correctly in your training programme, you should build some solid lean muscle," says Wilson. "This added muscle has tons of benefits for overall quality of life, function, and even joint and bone protection as we age."
What's the Hardest Muscle to Build?
While the muscles in the calves, forearms, triceps and obliques are known for being notoriously difficult to grow, your personal capacity to pack on mass is mostly genetic. "Some folks simply have an easier time developing certain muscles over others," says Wilson. "For instance, my traps have always grown without me ever having to do a single shrug, but I can't get my biceps to grow much even when I train biceps three or four times per week."
With that said, it matters whether the muscle in question is made up primarily of 'fast-twitch' or 'slow-twitch' fibres. Fast-twitch muscle fibres provide powerful forces for short durations, so they support activities like sprinting and weightlifting. Slow-twitch muscle fibres aren't very strong, but they're built for endurance (think, running a marathon). Surrounded by plenty of blood vessels, they have a potent supply of oxygen, making them resistant to fatigue.
"It would be reasonable to assume that muscles with a higher percentage of fast-twitch muscle fibres are easier to build," says Wilson. "Generally, fast-twitch muscle fibres grow more in response to resistance training. For most folks, this means that muscles like the pectorals, biceps, triceps and even lats should be a little easier to grow, whereas the glutes, calves and traps might be tougher, since they have a higher percentage of slow-twitch fibres."
How to Maximise Hypertrophy
Effective hypertrophy requires a delicate balance between training, nutrition and recovery. To recap, shifting tin damages your muscle fibres, forcing your body to repair them thicker. To work this magic, it requires extra calories. Rest is the final – but no less essential – piece of the puzzle, because your body needs time to repair the damage you've unleashed.
Take stock of this hypertrophy trifecta and you'll foster lean mass without burning yourself out (or sending surplus calories to your midriff). Here's how it's done:
How to Train for Hypertrophy
Rule #1: keep challenging your muscles with progressive overload. "Each session, increase the stimulus placed on the muscle the previous week or session," says Taylor. "For example, if last week you squatted 100kg for 10 reps, and this week 11, that is a greater stimulus. The 'perfect rep range' isn't really a thing, nor is the perfect training programme. Consistently progressing week on week will damn sure lead to hypertrophy over time."
Structure your training by targeting each muscle group twice per week, says Wilson. "Hit each muscle group with two exercises each time you train it, so that it gets four good exercises every week," he says. "Perform three or four sets of every exercise in the six to 12-rep range, but don't be afraid to throw the occasional set of 20 to 30 reps in, as well as the occasional set of three to five reps, to ensure you're getting stronger in multiple rep ranges."
How to Eat for Hypertrophy
Your body needs fuel, and plenty of it. "Recent research paints the energy cost of building muscle at around 400 to 500 calories a day," says Wilson. "So if you have an idea of your maintenance calories, add about 500 to support muscle growth. Make sure you're eating about a gram of protein per pound of bodyweight (2.2g/kg) to support muscle repair."
And don't forget to hydrate. "Aim for 1mL of water for every calorie burned throughout the day," he continues. "If you have a smart watch, track your total calorie expenditure throughout the day for a rough estimate for how much water you should drink. For my workout days, I burn around 3,500 calories – therefore, I drink 3.5 liters of fluid for the day."
How to Recover for Hypertrophy
Ditch the 'no days off' mentality. Rest is crucial for hypertrophy. "If you're not recovering, you're not growing," says Taylor. After training, "protein synthesis seems to remain elevated for 48 to 72 hours," he says. "This means that if we have trained a muscle group, providing it has recovered, we can train it again two to three days later." When it comes to muscle-building supps, protein powder has nothing on a decent night's kip.
"One massive component people often skimp out on when trying to maximise hypertrophy is sleep," says Wilson, who advocates for a minimum of seven hours per night "Remember, you're only in the gym for one or two hours a day," he says. "What you do the other 22 to 23 hours is what really makes the difference. Multiple studies have shown that sleep can aid in muscle growth and recovery, improve athletic performance and enhance fat loss. Sleep is that secret supplement that people keep asking about."
The Ultimate Full Body Hypertrophy Workout
Reckon you're ready? Grow your entire body in one punishing swoop with the hypertrophy workout below, created exclusively by Taylor for Men's Health. After warming up, follow the exercises in order, noting the sets, reps and rest specific to each move.
Back Squat
4 sets, 6 reps. 90 second rest between sets
Stand with your feet more than shoulder-width apart and hold a barbell across your upper back with an overhand grip – avoid resting it on your neck. Hug the bar into your traps to engage your upper back muscles. Slowly sit back into a squat with head up, back straight and backside out. Lower until your hips are aligned with your knees, with your legs at 90 degrees – a deeper squat will be more beneficial, but get the strength and flexibility first. Drive your heels into the floor to push yourself explosively back up. Keep form until you're stood up straight.
Barbell Romanian Deadlift
3 sets, 8 reps. 90 second rest between sets
Hold your barbell in front of your thighs. Draw your shoulders back and keep your spine straight. Slowly lower the barbell to the ground by pushing your hips back. Keep your chest open and wide. When the weight is below your knees, thrust your hips forward and return to the starting position.
Flat Dumbbell Bench Press
4 sets, 6 reps. 90 second rest between sets
Lie back on a flat bench holding two dumbbells over your chest with a shoulder-width overhand grip. Your palms should be facing towards your feet. Press the weights above your chest explosively by extending your elbows until your arms are straight. Lower the dumbbells slowly back to the starting position, until they skim the middle of your chest.
Neutral Grip Pull-up
3 sets, AMRAP. 90 second rest between sets
Grab the handles of the pull-up station with your palms facing away from you and your arms fully extended. Your hands should be around shoulder-width apart. Squeeze your shoulder blades together, exhale and drive your elbows towards your hips to bring your chin above the bar. Lower under control back to the start position.
Bulgarian Split Squat
3 sets, 10 reps. 60 second rest between sets
Have one leg resting on the bench behind you, laces down. Your front foot should be three footsteps out from the bench. Squat with your standing leg until the knee of your rear leg almost touches the floor. (If it doesn't, lower the bench). Push up explosively through your front foot to return to the start position.
Dumbbell Lateral Raise
3 sets, 12-15 reps. 60 second rest between sets
Pick up two dumbbells and hold them by your sides with your palms facing your body. Keeping your upper body still – that means no swinging – lift the dumbbells out to your side with a slight bend at your elbows. Lift until your arms are parallel to the floor, then slowly lower to the start position.
Chest-Supported Dumbbell Row
3 sets, 15 reps. 60 second rest between sets
Lie face down on the bench with your feet other side to keep you stable. Hang the dumbbells beneath you using a neutral grip. Keep your head up and bring your shoulder blades together as you row the weights towards your chest. Lower to the starting position under control.
Lying EZ Bar Skullcrusher
3 sets, 10-12 reps. 60 second rest between sets
Grasp the inner grips of the EZ bar using the overhand position and extend your arms straight up. Keeping your elbows fixed and tucked in, slowly lower the bar until it is about an inch from your forehead. Slowly extend your arms back to the starting position without locking your elbows.
Incline Dumbbell Curl
3 sets, 10-12 reps. 60 second rest between sets
Sit down on a bench set to a 45-degree angle holding two dumbbells at your sides with an underhand grip. Curl the weights up to shoulder height, squeeze your bicep then return under control to the start position.
Seated Calf Raise
3 sets, 15-20 reps. 45 second rest between sets
Sit down at the leg press machine and rest your feet so just your toes are resting at the bottom of the platform. Push back as far as you can while keeping your feet against the platform. Return under control to the start position and repeat.
Hanging Leg Raise
3 sets, 10-15 reps. 45 second rest between sets
Grab a pull-up bar and lower yourself into a dead hang. Let your legs straighten and pull your pelvis back slightly. Tense your core and raise your legs until your thighs are perpendicular to your torso. Hold then lower slowly back to the starting position.
