It’s ingrained in your brain that endurance exercise, movements like running and cycling that get your heart rate up for sustained periods, is best for cardiovascular health. That’s what the American Heart Association and most experts say. It’s true that endurance exercise has benefits for the health of your heart. For one, this type of training can increase your aerobic capacity, the ability to deliver oxygen to your muscles. That’s important since studies correlate higher aerobic capacity with a lower risk of cardiovascular disease.
Endurance exercise also lowers blood pressure and has a favorable effect on lipids, particularly triglycerides and HDL-cholesterol, the “good” form of cholesterol associated with a lower risk of cardiovascular disease. Workouts that keep your heart rate up for sustained periods also improve insulin sensitivity and help lower body weight. Plus, exercise, in moderation, has an anti-inflammatory effect. We now know that inflammation plays a role in cardiovascular disease. Inflammation may be the initial event that triggers the build-up of plaque inside your blood vessels, including those that deliver blood to the heart. By keeping inflammation in check, we can lower the risk of a number of chronic health problems including heart disease.
The Impact of Strength Training on the Heart
Keep doing exercise that boosts your heart rate for sustained periods, but don’t underestimate the importance of strength training for the health of your heart. A study published in JAMA Cardiology shows that strength training has unexpected heart health benefits.
How might strength training benefit the health of your heart? Along the outside of your heart lies a layer of fat called pericardial adipose tissue. As you probably know, adipose tissue is another name for fat. This layer of fat serves as a source of energy to the heart muscle and also protects it against the damaging effects of free fatty acids. However, research suggests that too much fat around the heart may be harmful. In fact, it’s linked with cardiovascular disease and a reduction in heart function.
What does this have to do with weight training? The JAMA Cardiology study found that subjects who weight trained had lower quantities of pericardial adipose tissue around their heart while aerobic or endurance exercise had little impact. However, both weight training and aerobic exercise reduced the amount of epicardial fat, another type of fat you find in the area of the heart. It, too, is associated with a higher risk of cardiovascular disease. In the study, weight training was better for trimming pericardial fat, but the combination of aerobic and strength training trimmed the most total fat from around the heart.
How might strength training reduce fat around the heart? Scientists aren’t sure how and why. One theory is that strength training boosts fat burning and that includes fat around the heart. Therefore, regular strength training may decrease the amount of fat available to deposit around the heart.
More Evidence that Strength Training is Heart Healthy
If that were the only way strength training improves heart health, it would be enough, but there’s more! A large study called the NHANES study looked at the exercise and lifestyle habits of more than 4,000 adults. This study found that both forms of exercise, endurance and strength training, were associated with a lower risk of cardiovascular disease, but strength training was more strongly correlated with a reduction in cardiovascular risk than endurance exercise. That might be surprising since we think of weight training as being the exercise we do to build strength and endurance exercise to protect the health of your heart. They may both be protective! In fact, it seems that any kind of physical activity has benefits for heart health.
What are ways, independent of that amount of fat around the heart, that weight training reduces cardiovascular risks? After all, lifting weights with long rest periods between sets doesn’t boost aerobic capacity like endurance exercise does and it won’t make the heart a more efficient pump. One way it may be beneficial is by its impact on insulin sensitivity. Insulin resistance is a major risk factor of cardiovascular disease and studies link strength training with improvements in how cells handle insulin. In turn, this can lower blood glucose and reduce the risk of type 2 diabetes.
You might think that the improvements in insulin sensitivity that come with strength training are due to weight loss, as obesity is linked with insulin resistance, however, studies show that weight training improves insulin sensitivity even in people who don’t lose weight.
Regular strength training also helps keep visceral fat in check. Visceral fat is an unhealthy form of deep belly fat that has risky metabolic effects. It’s distinct from the pinchable fat that builds up in other areas, such as around the thighs and hips. Studies show that visceral fat produces inflammatory chemicals that drive insulin resistance and damage the inner walls of arteries that carry blood to the heart. No wonder deep tummy fat is linked with cardiovascular disease and other health problems as well!
The Bottom Line
Aerobic and endurance exercise is still a heart-healthy form of exercise and it’s the best way to improve your aerobic capacity and endurance. You can also get heart health benefits by picking up the pace and doing high-intensity interval training. In fact, some research suggests that high-intensity training is more beneficial for heart health than moderate-intensity exercise and it’s more time expedient.
But don’t assume that strength training has no benefits for the old ticker and for your blood vessels. Your best bet is to do a combination of aerobic exercise and strength training. Plus, strength training offers other benefits you won’t get from aerobic exercise. Namely, it builds strength! Doing both forms of exercise ensures you get maximal health and fitness benefits and it keeps it interesting too. Make time for both in your fitness routine and reap the rewards!
· J Phys Ther Sci. 2015 Nov; 27(11): 3503–3509.
· Journal of Cardiology 65 (2015) 2–4
· Medscape Family Medicine. “Strength Training May Best Aerobics for Cardioprotection”
· Medscape Family Medicine. “Endurance, Resistance Exercise Shrinks Cardiac Fat in the Obese” July 8, 2019.