You probably already know the many benefits of strength training, chief among them having increased strength because your muscles will get bigger and stronger. You may not know that there's a term for that: hypertrophy, which is the process of breaking down and building muscles back up. It may sound alarming, but our muscles adapt to stimuli (e.g., hard workouts) and repair themselves, leading to positive results for your body. We asked experts how hypertrophy works, why it's important, and how we can structure our workouts to achieve it effectively.
Meet the Expert
What is Hypertrophy?
Hypertrophy, or muscular hypertrophy related to strength training, is the enlargement of muscle size. Explains Katie Kollath, ACE CPT and co-founder of Barpath Fitness, “when protein synthesis exceeds muscle protein breakdown, muscle hypertrophy will occur.” Or in other words, when different muscles are stimulated or overloaded due to resistance training movements, muscle fibers are damaged, but they repair themselves bigger and stronger. It doesn’t happen overnight; “generally, you’ll see effects within eight weeks of starting a [workout] program,” says Lauren Saint-Louis, a Tier X Trainer at Equinox, “and more noticeable changes after three-to-four months.”
What Are the Benefits of Hypertrophy?
The benefits of hypertrophy include bigger muscles, which leads to increased strength. But beyond that, Saint-Louis says hypertrophy can also lead to better joint structure and support, less tightness and weakness, and a more toned and sculpted physique.
Kollath agrees that the benefits are aplenty. “The more muscle you have, the better your body composition will be,” she says. “So having muscle on your body actually helps to burn body fat.” Some studies show increased muscle mass is associated with lower all-cause mortality in older adults.
While it’s beneficial for everyone to have some muscle mass on their body, both Kollath and Saint-Louis agree that bigger isn’t always better. For example, you don’t need to make bulking up your main and only objective. Ultimately it depends on personal preferences, goals, and what supports your body the best.
How Do You Achieve Hypertrophy?
To really build muscle, you need to incorporate resistance or strength training into your workout routine. “Hypertrophy is achieved most effectively through strength training with added resistance, usually in the form of free weights,” says Saint-Louis. Another option is through calisthenics, which is training that only requires your own body weight (think squats, push-ups, and crunches). Calisthenics “requires the ability to lift and push your body easily and requires significantly more volume of sets/reps to achieve similar results. For example, four sets of 8-15 reps will elicit a hypertrophy response, and you should train major muscle groups every three days to take advantage of the growth cycle,” she says.
For cardio lovers, that doesn’t mean you have to stop your favorite workouts. Saint-Louis says you can maintain your general cardiovascular conditioning at a low-intensity steady-state one or two times a week between harder or HIIT workouts. “Rest days inherently get built into your program as if each body part is trained two-to-three days apart, then they will recover in time before their next session.“
Kollath agrees that it’s equally important to let them recover when you're working your muscles hard. When you do resistance training, you’re actually breaking down muscle proteins during the workout. She explains that you need enough recovery built into your schedule to let those proteins build back up and get even stronger. She suggests taking recovery days between workouts, but that doesn’t give you a free pass to sit around and watch TV all day. “Make sure you're maybe doing some lighter movements or stretches throughout the day and definitely try to walk/move as much as possible,” she suggests. Sleep is also important to help recover from hard workouts. Kollath suggests trying to get seven to nine hours of sleep per night and ensuring quality sleep like REM or deep sleep.
In addition to how you’re moving your body, another factor to consider is what you’re putting into it. Hydration and nutrition are essential. “In order to get your muscles to grow, you also have to be eating a caloric surplus. This means taking in more calories than you’re burning throughout the day.” However, not all calories are equal, so she recommends choosing high-quality food sources (whole foods vs. processed ones). “Focus on getting adequate protein as well—this will help stimulate protein synthesis so your muscles can utilize those proteins to build muscle,” says Kollath. Adds Saint-Louis, “Carbs and protein are your best friends when it comes to building muscle mass. If you're eating clean proteins and carbs, there's little risk for becoming too big, and your body will use it appropriately.”
Is There Anyone Who Shouldn’t Aim for Hypertrophy?
Everyone should incorporate hypertrophy in some way and can benefit from it, say Kollath and Saint-Louis. If you’re an endurance athlete, you may not want too much muscle mass to inhibit your sport, says Saint-Louis.
What Are the Best Types of Workouts to Achieve Hypertrophy?
“Compound movements are a must for hypertrophy,” says Kollath. These are exercises that simultaneously work multiple muscle groups and include squats, deadlifts, pressing, pulling, lunging, and carrying. You can progress these movements using only bodyweight if programmed properly, or you can do them with external loads (e.g., barbell squats, bench presses, etc.)
For the general population, Kollath says doing a full-body workout—incorporating several compound movements to hit all your major muscle groups—two-to-three times a week is usually more than enough (if intensity and progressive overload in the programming are applied properly), especially if your goal is to move more and feel great. If you’re more advanced, Kollath says you can also do resistance training more often and split up body parts.
Saint-Louis has a similar recommendation: Use compound movements to make up the base of your program, and layer in assistance exercises that target more specific muscle groups, and use things like dumbbells, cables, and machines. ”A general blueprint is to start your workout with compound larger movements and larger muscles and progress to smaller, specific exercises or muscles throughout the workout.“
Srikanthan P, Karlamangla AS. Muscle Mass Index As a Predictor of Longevity in Older Adults. Am J Med. 2014;127(6):547-553. doi:10.1016/j.amjmed.2014.02.007
Vitale KC, Owens R, Hopkins SR, Malhotra A. Sleep Hygiene for Optimizing Recovery in Athletes: Review and Recommendations. Int J Sports Med. 2019;40(8):535-543. doi:10.1055/a-0905-3103