The process of lifting weights to gain muscle might be one of the most obvious (or at least well-known) cause-and-effect relationships, but putting on muscle is just one of the many scientifically-proven benefits of strength training. 

In fact, when she’s working with clients, Sarah Cash Crawford, doctor of physical therapy and the founder of Anchor Wellness and WAVE Physical Therapy, makes it a point to reinforce the idea that the goal isn’t just to get stronger. (Although that’s certainly a win in itself.) The mission is also to help your muscles, bones, and joints—as well as your brain, blood sugar, and organs—work better together to support your daily life, Crawford explains. 

“It’s really about building a strong foundation so you can move with confidence and ease at every stage of life,” Crawford says. “Research consistently shows that incorporating resistance training just two to three times per week can have profound long-term health benefits.” And you don’t need to lift heavy barbells or spend hours at the gym every day to accrue these gains, she adds. 

Ahead, we dive into the science and speak with fitness experts to reveal the biggest benefits of strength training. Warning: You’ll want to have your sneakers and water bottle ready after reading this, because the perks are powerful.

What Is Strength Training? 

Strength training, aka resistance training, is “any form of exercise that involves using external force—whether it’s your own bodyweight, dumbbells, a barbell, resistance bands, or machines—to teach your muscles to work harder than they’re used to,” says Peloton instructor Assal Arian. “You break down muscle fibers and your body rebuilds them stronger.”

Strength training doesn't need to look like hoisting huge dumbbells or fully loaded barbells from the floor to overhead. Simple bodyweight movements, such as squats and planks, done with good form, also “count” as strength training. The goal is to gradually challenge your muscles in a progressive way that will enhance muscle strength and overall function, adds Catherine Powell, doctor of physical therapy and owner of Powerful Physical Therapy. (In case you missed it, our guide to strength training has a deep dive into the types of strength training and how to get started.)

12 Science-Backed Benefits of Strength Training 

Whether you’re just getting started with strength training or have been busting out burpees and bench press reps for years, it’s common and totally normal to find your motivation flagging some days. The next time you’re tempted to skip leg day, turn to this list of a dozen legit benefits of strength training to get you going.

1. Strength Training Is Accessible for Everyone

“Couch to 5K” programs are popular to ease runners into the sport, and maybe “couch to 5 reps” should be next. You need not be young, fit, or familiar with every strength training move under the sun to start.

“The truth is, strength training can and should be adapted to all fitness levels and ages. It’s never too late to start, and the benefits are profound at every stage of life,” Crawford confirms. 

Strength training is for everyone, regardless of age or experience, Assal adds. In fact, it’s more important as we get older to combat muscle loss and stay functional. (More on this shortly.) And you need not lift heavy to see results, Assal says: “Progression can look like improving form, increasing reps, slowing the tempo, or reducing rest. It’s about the challenge, not necessarily heavier weight.”

Intimidated by the weight room? All of Peloton’s strength training classes are designed to be done in the comfort of your own home and include plenty of bodyweight or no-equipment options.

2. Strength Training Helps Combat Aging-Related Muscle Loss

Research suggests that, starting around age 30, you naturally lose about 3 to 8 percent of your body’s lean muscle mass. If you don’t strength train, you’ll likely lose lean muscle mass (and the strength that comes with it) and develop a higher percentage of body fat, says Heather Baker, physical therapist at Swedish Hospital—Endeavor Health.

As it compounds over the years, this body mass shift will show up on the scale, in the mirror, and in your quality of life. 

3. Strength Training Helps Build and Maintain Functional Strength

Functional strength is the strength your body needs for activities performed in daily life, sports, or specific tasks. By improving functional strength, resistance training “helps people maintain their independence throughout their lifetime,” Powell says. “It allows someone to get on and off the floor independently, squat down to look at groceries on the bottom shelf, carry those groceries in from the car, and lift children and grandchildren without fatigue.” 

Being able to keep up with these activities of daily living keeps you mobile, independent, and doing what you love for longer, Assal
explains.

4. Strength Training Keeps Your Metabolism Humming

“One serious benefit of strength training is that it turns your body into a more efficient engine,” Assal says. That’s because, as you add more muscle to your frame, you naturally increase your metabolism, burning more calories during exercise and at rest, Baker says.

Over time, this can make it easier to maintain or improve your body composition, if that’s a goal for you. “For most people, strength training leads to a leaner, more toned physique,” Assal says.O ne 2019 study published in Frontiers in Physiology, for example, found that resistance training twice each week was enough to help seniors maintain a healthy body composition, despite the tendency for our bodies to lose muscle mass as we age. 

5. Strength Training Supports Good Posture

Though it’s an often-overlooked benefit, strength training will also help improve your posture. The muscles in your core, back, neck, and shoulders play a pivotal role in helping you sit and stand and tall and proud. Building strength and muscular endurance in those muscle groups helps you maintain good posture for long periods (for example, when you’re sitting at your desk). 

This isn’t just an aesthetic thing. Bad posture can lead to muscle tension, pain, and cause wear and tear on your spine and joints. The good news: Strength training increases postural control, which can in turn reduce the risk for issues like low back pain.

Beyond that, being strong enough to maintain the natural curvature of your spine can “improve breathing and energy levels,” according to Assal, and may help counteract the aches (think: “tech neck”) that often come along with overtime on devices.

6. Strength Training Improves Bone Health

Any exercise that puts stress on bones, such as lifting weights or performing a set of bodyweight lunges, “encourages bone cell activity which counteracts the natural loss of bone with age and even helps to build bone. This leads to stronger, denser bones,” Baker says. 

Stronger bones means a lower risk for developing osteoporosis, a condition in which a decline in bone mass and bone mineral density is so substantial, it may increase the risk for fractures.

“This is especially important for women as estrogen levels decline,” Crawford says, since that hormone plays a critical role in maintaining bone health throughout the lifespan.

7. Strength Training Aids In Hormonal Balance

Hormones, powerful chemical messengers created in our endocrine glands, play a role in everything from metabolism and reproduction to sleep and stress levels. Hormones naturally shift throughout the day and our lifetime; however, even minor changes from your own “normal” can make a major difference in how you feel, according to the Cleveland Clinic.

“Strength training can help regulate hormones, support healthy menstrual cycles, and improve sleep by balancing cortisol and increasing growth hormone and testosterone in a natural, healthy way,” Assal explains. “Cardio and strength are both important for well-being, but strength training offers metabolic, hormonal, and long-term health benefits that cardio alone simply can’t match.”

8. Strength Training Promotes Better Sleep

Even outside of the hormonal impact, a strength training practice is linked to better sleep. One small 2022 study conducted at Iowa State University found that folks who perform three one-hour resistance training sessions per week tend to fall asleep faster and snooze more soundly than their peers who did cardio or a combo of cardio and strength for the same amount of time. A 2018 meta-analysis of 13 studies published the journal Sleep Medicine Reviews echoes this sentiment: Resistance training is particularly powerful at promoting sleep quality.

And those sleep benefits have cascading effects. “High-quality sleep makes day-to-day life feel easier and more manageable,” Crawford says.

The scientific jury is still debating why this occurs, but they believe resistance training taxes our muscles in such a way that sends a loud message to the brain that it should sleep well to allow for deep repair required for muscle protein synthesis (the process of building new proteins to repair and grow muscle tissue). 

9. Strength Training Can Reduce the Risk of Injuries

Big muscles like glutes and quads tend to get a lot of time in the spotlight, but smaller, deeper stabilizing muscles matter too. “Strengthening the muscles that surround joints improves stability and lowers injury risk,” Assal says.

Besides bolstering our joints, strength training improves body awareness and movement patterns, Crawford adds. As you become more in tune with your muscles and how your body moves, you naturally start to move more efficiently and with better alignment, even outside the gym. 

“Resistance training has been shown to improve balance and coordination, helping to reduce the risk of falls as we age,” Crawford says.

10. Strength Training Helps Regulate Blood Sugar.

It’s normal for blood sugar to spike after eating, but persistently high levels (aka hyperglycemia) can be dangerous, damaging blood vessels and increasing your risk for more serious health issues. 

Exercise, in general, can aid in managing blood sugar, and strength training plays a specifically helpful role: it makes your muscles more sensitive to insulin and primes them to absorb sugar from the bloodstream directly. As such, research shows that strength training before eating can increase the body’s ability to effectively use the sugar you consume and reduce how quickly glucose enters your bloodstream, according to UCLA Health. Translation: You can steer clear of that uncomfortable blood sugar spike and crash, and are at lower risk for prediabetes and type 2 diabetes.

11. Strength Training May Help You Live Longer

We’ve already covered the benefits of strength training in relation to body mass, bone health, and quality of life, and science proves that there is a direct correlation with length of life, too.

One 2022 research review published in the British Journal of Sports Medicine found that strength training is associated with a 10 to 17 percent reduced risk of premature death from all causes, including, but not limited to, three of the top seven leading causes of death in America: cancer, heart disease, and diabetes. How much strength training is enough to potentially lead to longevity benefits? Just 30 minutes twice each week should do it, according to Harvard health experts.

12. Strength Training Enhances Mood, Confidence, and Mental Health

If all of these facts don’t make you want to strength train, perhaps this last one will. “It’s also well documented that strength training has tremendous effects directly on mental health,” Baker says. “It helps to improve focus, reduces depressive symptoms, and increases feelings of anxiety—in both individuals with and without formal mental health diagnoses.” 

Exercise of all kinds has been shown to turn down the volume of stress hormones like adrenaline and cortisol while triggering that much-discussed “endorphin high.” Resistance training deserves extra flowers, Crawford believes, because “setting and achieving strength goals, no matter how small, reinforces confidence and a sense of capability.” The discipline required to stick with a strength training plan and reach for the next weight up (and the next) “teaches us patience, focus, and resilience, which often transfers into other areas of life,” Assal says.

The Takeaway

Strength training is a vital part of any fitness routine for muscle maintenance and so much more. 

“Resistance training burns fat, increases lean muscle mass, aids in weight management, promotes bone health, decreases the risk of many chronic diseases, and enhances mood and mental health,” Baker summarizes.

Ready to pump up your routine? Peloton’s library of thousands of strength classes are just a click away on the Peloton App.