It has become a familiar scene to gymgoers and gym owners: Many elliptical machines sit empty while the heavy dumbbells are in high demand.
Over the past several years, strength training has surged in popularity, according to fitness industry experts, due to a combination of pandemic-induced habit changes and growing awareness of the health benefits of muscle strengthening.
Bente Smart, director of education for Crunch Fitness, said the global gym chain has shuffled its spaces to better cater to its members’ interests.
“We’ve definitely been renovating and increasing our functional spaces,” Smart said, “so including things like more turf area for battle ropes, medicine balls, TRX, suspension trainers and less cardio equipment to adapt to the growing need for resistance training.”
On ClassPass, where members choose from a range of fitness classes, strength training was the most popular type of workout last year, with a 94% increase in reservations in those classes from the year prior. More than 60% of ClassPass users now include strength training in their routines, the company said.
Experts offered various hypotheses as to why people have shifted their exercise regimens. Brad Roy, editor in chief of the American College of Sports Medicine Health and Fitness Journal, said home workouts that people took up during the pandemic may have played a role, since functional and resistance band exercises are easy to do outside the gym. Many people also relied on online fitness videos during the pandemic, which might have made strength training more accessible.
Lauren McAlister, a ClassPass wellness specialist, suggested that misinformation around weight training has in the past led women to believe they will develop a bodybuilder-like physique.
But recently, she said, “we’re kind of coming into our own more and more and saying, ‘No, I want to be strong. I want to be capable. I want to be able to experience all the benefits of a strength training program.'”
"And I think social media has been a really cool way to see women doing that and giving other women permission to say, ‘Oh, I’m going to try that.’”
McAlister, who co-owns a fitness studio, said its classes have shifted to focus more on weight-bearing movements in response to customer requests. Strength training may appeal to some people as a way to slow down at the gym following the challenges of the pandemic, she said.
“We’ve all been really stressed for a long time,” McAlister said, “so taking things at a little bit of a slower pace and really focusing on form and focusing on sort of the fundamental movement patterns — that’s why I think people are leaning towards that.”
According to an annual survey in the American College of Sports Medicine’s journal, strength training with free weights ranked as the second-most popular fitness trend in 2023, after wearable fitness technology. Bodyweight training came in third, while two highly ranked forms from 2021 and 2022 — online training and home exercise gyms — fell to numbers 21 and 13, respectively.
Strength training is characterized by a contracting of the muscles, as opposed to aerobic or cardiovascular training that aims to raise the heart rate. Weightlifting, resistance band work and pilates and yoga are all forms of it.
A large body of research shows that strength training can bring particular health benefits.
“In terms of muscle-strengthening activities or weightlifting, there are so many different positive health outcomes,” said Duck-Chul Lee, a professor of kinesiology at Iowa State University. That list includes diabetes prevention, bone health and improved functional ability in older adults, he said.
A study of over 400,000 people published last year found that those who regularly practiced strength training along with aerobic exercise had a lower risk of death than those who did just aerobic training. And an analysis of 16 previous studies suggested that regular strength training was associated with a 10% to 17% lower risk of cardiovascular disease, diabetes, lung cancer and death overall.
Dr. Jacob Erickson, a sports medicine physician at the Mayo Clinic, said resistance training is a smart option for people working toward weight loss because it raises their metabolic rate, prompting the body to continue burning calories for up to three days afterward.
“Walking, jogging, the treadmill will make it easier to do day-to-day things like walking upstairs, taking your dog for a walk, chasing after kids, whereas resistance training will actually strengthen the muscles,” Erickson said. “As we age, in general, our lower body strength and muscle mass will kind of go away faster, so it becomes increasingly important to strength train.”