What Is the Right Balance of Strength Training to Cardio?

Q: How much cardiovascular exercise versus strength training should I do each week?

If you want to live a long, healthy life, exercise is nonnegotiable. Research is clear that both cardiovascular exercise and strength training are important for fitness and disease prevention. But with limited time in your schedule, it can be tough to determine the most effective (and efficient) way to reap the benefits of breaking a sweat.

How often should you be getting your heart rate up, and how much time should you devote to working your muscles? We spoke to exercise experts to find out whether there’s an ideal balance and how to incorporate cardio and strength training into your routine.

Cardio and strength training help the body in different ways. Cardiovascular exercise — anything that increases heart rate — promotes heart and lung health and reduces the risk of high blood pressure, diabetes and cancer. Strength training boosts the metabolism by building lean muscle mass, preventing obesity and limiting bone loss.

When it comes to longevity and overall health, experts agree a combination of the two is most beneficial. “I wouldn’t say it’s cardio versus strength, because they are partners,” said NiCole R. Keith, a professor of kinesiology at Indiana University-Purdue University Indianapolis. “We need to be doing both.”

Recent research pinpoints how much of each exercise is most likely to increase longevity. A 2022 study published in the British Journal of Sports Medicine found that a combination of cardiovascular and strength training was associated with a lower risk of mortality than cardio alone. Even one hour a week of cardio alone led to a reduction in mortality risk, with three hours yielding the most benefit.

Similarly, the American College of Sports Medicine and the Centers for Disease Control and Prevention recommend that adults between the ages of 18 and 65 aim for 150 minutes of moderate-intensity cardiovascular exercise per week. According to Dr. Keith, that’s when you can talk, but you feel winded. Cut that number in half if you’re doing vigorous cardio, where you’re too out of breath to speak.

Experts recommend additional muscle strengthening exercise at least twice a week to further lower the risk of mortality. But strength training is about sets and reps rather than duration, according to Dr. Keith.

The C.D.C. and A.C.S.M. recommend strength training exercises that include each major muscle group (your upper body, lower body and core). Dr. Keith recommends lifting light weights for three sets of eight to 10 repetitions to maintain muscle health; if your goal is to build bigger muscles, lift heavier weights for three sets with fewer reps.

Don’t stress about achieving a perfect balance. “I honestly don’t obsess over the numbers,” said Dr. Christopher McMullen, a sports medicine physician at the University of Washington Medical Center. You’ll be more likely to stick with a routine if it works for your schedule and preferences.

The recommended 150 minutes of cardio per week can be broken down into five 30-minute sessions. And you should strengthen your core, upper and lower body two times per week. But that doesn’t mean you have to work out every day, or that you have to do your strength exercises separately.

The C.D.C. is clear that exercise is still beneficial when people break it up — say, doing a few shorter, more intense workouts. Strength and cardio exercise can also be done in the same workout session. “You can work on one muscle group each time you do cardio,” Dr. Keith said.

Some research suggests that a cardio workout before strength training enhances performance. “You may be priming your muscles to be more ready for a strengthening activity if you prompt them with an aerobic activity first,” Dr. McMullen said.

Aja Campbell, a certified strength and conditioning specialist in Queens, said she encouraged clients to start with their priority. If you primarily want to build strength, start with weights. If your goal is to improve cardio fitness, start with a jog.

No matter what order you pick, be mindful about intensity — going too hard can increase the risk of an injury that keeps you from exercising altogether. “Generally speaking, if I pair cardio and strength in a session, I pair something high intensity with a low-intensity activity,” Ms. Campbell said. “You want to be able to recover, while still getting the exercise benefits you need for the week.”

Rather than seeking a precise balance, choose a mix of activities. Many exercises include a combination of strength and cardio. You can elevate your heart rate in a weight lifting class, or you can work your leg muscles when you run at an incline. Just as importantly, Dr. McMullen recommends picking activities you actually enjoy. “People can maintain an exercise regimen when it’s something they like to do,” he said.

Ashley Abramson is a Milwaukee-based freelance journalist.