Build More Muscle Without Weights

Ready. Set. Build some muscle! Research shows sprint interval training can build lean muscle mass and improve metabolic health in menopausal women.

By Selene Yeager

***This article was originally published on June 23, 2021. It has been updated by the author.*** 

By now you know the mantra for making muscle as a menopausal woman: Lift heavy sh*t.

Well, we've got some good news. Another of our training favorites, high-intensity interval training (HIIT), specifically sprint interval training (SIT), not only helps improve your power and cardiovascular fitness, but also can help menopausal women increase lean muscle mass, according to a study in Medicine & Science in Sports & Exercise.

In the study, researchers had 39 healthy, but untrained women and men, ages 50 to 68, perform 15-minute maximal power cycling bouts (a.k.a. sprint interval training) three times per week for eight weeks. The workouts consisted of a warm-up and then short, full-throttle sprints followed by a period of rest.

The first week, the participants performed 15 4-second sprints, followed by 56 seconds of rest. During weeks two through four, they shortened the rest period to 41 seconds, completing 20 sprints total. Finally, during weeks five through eight, they reduced the rest period down to 26 seconds and completed 30 bouts. (If you’re doing the math, the actual hard exercise time is only 60 to 120 seconds total for these workouts.)

By study’s end, the sprint trainers got aerobically fitter, improving their VO2 peak (the highest amount of oxygen they could use) by 9.8 percent and the power they could produce at that peak by 8.2 percent. They also increased their total lean body mass by 1.5 percent and their thigh muscle mass by 3.7 percent. (These volunteers were untrained, so results may vary, but if you’re not hitting those super high intensities in training, you’re sure to reap benefits, too. I recently re-introduced SIT back into my training after a several weeks off and was surprised how quickly I noticed the muscle benefits.)

This isn’t the first study to show the muscle-making powers of sprint interval training (SIT). In a 2019 study also published in Medicine & Science in Sports & Exercise, researchers had a group of postmenopausal women ages 47 to 59 perform 20 minute bouts of SIT—alternating 8 seconds of sprinting on a stationary bike with 12 seconds of easy pedaling—three times a week for eight weeks. By study’s end, the women lost fat, regained muscle mass, and also improved their aerobic fitness by 12 percent.

SIT for Menopausal Muscle & Metabolic Health

Other research shows this type of SIT training is superior to more moderate endurance training for reducing potentially harmful visceral (deep abdominal) body fat. 

SIT works its metabolic magic on a few fronts. For one, it jump starts fast-twitch muscle fiber recruitment. Those are the powerful, snappy fibers that generally sit by the sidelines during endurance activity. They’re also the first to go with age.

These types of max-effort intervals also coax your body to burn more fat for energy when you’re not exercising, which is important as you reach the menopause transition and your body naturally burns less fat at rest and stores more of it, says Dr. Stacy Sims, author of Next Level.

That type of high-intensity work demands carbohydrates and pulls a lot of glucose from your bloodstream, she explains. Your body responds by replenishing your muscle and liver glycogen stores with carbohydrate and using more of your fat while you’re at rest, because it knows you’re going to need those muscle stores to perform those intense exercise bouts again.

SIT training also strengthens and increases the amount of your energy-producing mitochondria; improves insulin sensitivity, and lowers fasting blood sugar levels, all of which is good for overall cardiovascular and metabolic health

“Pre-menopause, estradiol used to help with this blood sugar control; now you need high-intensity training to get the job done well,” she says.

Tabata intervals are a simple place to start. Named for Japanese scientist Dr. Izumi Tabata, who developed these workouts, Tabata efforts are super short and simple to do on nearly any piece of exercise equipment.

Do it: After a good warm up, push as hard as possible for 20 seconds. Go super easy for 10 seconds. Repeat six to eight times. Recover for 4 to 5 minutes with super easy activity. Repeat another set. Work up to 3 sets.