How Microtears Help You to Build Muscle Mass

It seems counterintuitive to purposely injure yourself during a workout, but that, in essence, is what you must do to build muscle mass.

That doesn’t mean you should reach for the heaviest barbell at the gym and attempt 100 repetitions daily,  orthopedic surgeon Michael Karns, MD says. Instead, it’s important to understand how these tiny injuries to muscle fibers, called microtears, help athletes build mass.

“Microtears are what happen after a muscle gets physically worked,” Dr. Karns says.

“Once these occur, the body sends good nutrition and good blood to the area to heal. This, in turn, is how you grow musculature.

Over time, if done correctly, the microtears you sustain from exercise will eventually accumulate to form muscle mass.

"You have to break muscle down to build it back up stronger,” he says.

Muscle-Building Tips

The process of repairing and adapting to microtears to increase muscle mass is called hypertrophy.

Dr. Karns outlines eight ways to maximize hypertrophy and minimize the chances of developing chronic fatigue, burnout or overstress:

Seek guidance. If you’re new to strength training, ask a strength coach, athletic trainer or gym teacher to model safe techniques and monitor your form. Going it alone may cause you to develop bad habits, which can lead to injuries that set back your efforts.

Remember weightlifting isn’t a standalone activity. Skipping the warm-up or cooldown may sideline you. Begin your workout with a few minutes of cardio to increase your heart rate and get blood flowing to the muscles. After strength training, perform static stretches to prevent cramping.

Go heavy. Achieving hypertrophy means lifting heavier weights and performing fewer repetitions.

“Lifting heavy weight results in the microtears critical to building muscle mass,” Dr. Karns says.

But know your limits. Pushing yourself to lift the heaviest weight you can manage while still maintaining proper technique is the goal. Forcing yourself to do biceps curls with weights so heavy that your back is arching is counterproductive and downright dangerous.

Take a break. Rest is necessary to repair muscle fibers and build muscle mass. Ensuring adequate rest between workouts is critical to your body’s muscle repair process.

“If you’ve overloaded a muscle group with weights, you have to give it time between workouts so the body rebuilds the muscle bigger,” Dr. Karns says. “Otherwise, you stumble into a period of overfatigue and chronic pain.”

Fill your plate and water bottle. Exercise alone will not increase muscle mass. Maintain a balanced diet that includes lean protein. Drink plenty of water before, during and after your workout.

Get your Zzzs. Lack of sleep can lead to improper technique, lack of motivation or an inability to lift your usual weight load.

Keep a journal. “An athlete can track his sleep, food and hydration via a journal,” Dr. Karns says. “Have the athlete write down how much they are drinking a day as well as what food they are putting into their body. You can take it even further and note pre-practice or game meals, post-practice or game meals, etc.”

Michael Karns, MD is an orthopedic surgeon at University Hospitals Sports Medicine Institute. You can request an appointment with Dr. Karns or any University Hospitals doctor online.