Can Low-Intensity Exercise Have Similar Health and Fitness Benefits as High-Intensity Exercise?

January 2, 2022

by Cathe Friedrich

Let’s face it. Some days you don’t want to do a challenging workout. You’ve had a long day at work and your body tells you that a high-intensity workout isn’t in the cards. Don’t sweat it! There’s no law that says you must do an intense workout every time you put on your exercise shoes.

The image of people sweating it out doing intense cardio and challenging strength training would lead you to believe that low-intensity exercise has no health or fitness benefits. You might assume you have to push yourself hard every time to get into tip-top shape and lower your risk of cardiovascular disease.

There’s plenty of evidence that less intense workouts are beneficial for your health too, especially if you’re older. One analysis of 15 studies found that older adults who did lower-intensity exercise experienced improvements in strength, flexibility, balance, and cognitive function. Yet these are untrained individuals. If you’re an older adult in tip-top shape, doing ONLY lower intensity exercise may lead to reductions in fitness, strength, and stamina.

Moderate-Intensity Exercise Improves Aerobic Capacity

Research shows to boost aerobic capacity, the ability of your heart to transport oxygen, and a marker of cardiovascular fitness, you need to exercise at a maximum heart rate of around 60 to 70% of your maximal heart rate for 20 to 30 minutes at a time. This happens when you jog or cycle at a moderate intensity.

To determine your maximal heart rate, subtract your age from 220. If you’re 50 years old, your maximal heart would be 170. To determine your optimal heart rate range to improve cardiovascular function, multiply that number by 60% and 70%. You can also get cardiovascular benefits by doing more intense exercise for short periods, as is popular with high-intensity interval training (HIIT).

Aerobic capacity is an important marker of health and mortality risk. Research shows that each 1-MET boost in aerobic capacity is linked with an 8 to 17% drop in mortality from cardiovascular disease and all causes. Moderate to high-intensity exercise boosts aerobic capacity.

Low-Intensity Exercise is Beneficial for Your Heart

But what about lower intensity exercise, exercise at a level where you can still easily talk in complete sentences or even sing? Leisurely exercise won’t improve your aerobic fitness, like moderate or high-intensity exercise, but that doesn’t mean it isn’t healthy for your heart.

Low-intensity exercise has some benefits too. For one, it breaks the sitting cycle. Any type of movement is better than sitting for heart health. Numerous studies link sitting for more than 6 hours per day with a higher risk of death from heart-related causes. However, some studies even suggest that low-intensity exercise can improve markers of cardiovascular health.

For example, one study found that healthy, middle-aged adults who took 10,000 steps three times per week for 2 months experienced a drop in their LDL cholesterol, the form associated with a higher risk of cardiovascular disease.

The Effect of Low-Intensity Exercise on Insulin Sensitivity

Good insulin sensitivity is a marker of optimal metabolic health and blood sugar control. Unfortunately, the incidence of insulin resistance and prediabetes is skyrocketing, placing the population at higher risk of type 2 diabetes and cardiovascular disease. Plus, insulin sensitivity drops with age. Even if you have good insulin sensitivity when you’re young, it declines with age.

One study carried out by researchers in the Netherlands looked at the effect of different exercise intensities on insulin sensitivity. A group of people did intense exercise for an hour a day and then sat for the rest of the day. A second group did 4 hours per day of walking at a leisurely pace and spent 6 hours sitting and 2 hours standing. The final group did no exercise.

The findings? The subjects who did low-intensity exercise for 4 hours each day experienced the greatest improvement in insulin sensitivity, greater than the high-intensity exercise group.

Why did the low-intensity exercise group fare better? Although the high-intensity group did an intense workout, they sat longer after their high-powered sweat session. In contrast, the low-intensity exercisers moved more and sat less, even though the intensity of their movements was less.

So, if intense exercise fatigues you to the point where you sit the rest of the day while low-intensity exercise keeps you out of the chair, the latter could be better for your metabolic health.

Low-Intensity Exercise Lowers Stress Hormones

Stress is harmful to heart health in more than one way. It activates hormones, like cortisol, that reduce insulin sensitivity and raise your blood pressure, and that’s unhealthy for your heart.

Low-intensity exercise, like walking in nature or a gentle yoga workout, helps lower cortisol. That’s better for your waistline too, since cortisol causes your body to store more fat around your waist and deep in your abdominal cavity, so-called visceral fat, the unhealthiest type.

Doing moderate to high-intensity exercise can raise your cortisol level, especially if you don’t give your body a chance to recover between intense exercise sessions. Your body needs time to recuperate, and your cortisol level needs to come down.

Here’s an added perk. A study found that low-intensity exercise reduces fatigue by 65%. There’s a reason you feel more energized after moving your body!

The Bottom Line

The best approach for fitness and health would be to do moderate to high-intensity sessions but include low-intensity workouts between your harder sessions to help your body recover. The higher intensity sessions improve aerobic capacity and directly enhance the efficiency of your heart muscle, while low-intensity sessions lower stress hormones and help you recover from more intense sessions. There’s a place in your workout for both, and they both have health benefits.

References:

Tse AC, Wong TW, Lee PH. Effect of Low-intensity Exercise on Physical and Cognitive Health in Older Adults: a Systematic Review. Sports Med Open. 2015;1(1):37. doi: 10.1186/s40798-015-0034-8. Epub 2015 Oct 20. PMID: 26512340; PMCID: PMC4612316.
Med Sci Sports Exerc. 2008 Jul;40(7):1263-70.
“Low-intensity exercise reduces fatigue symptoms by 65 ….” 28 Feb. 2008, uga.edu/low-intensity-exercise-reduces-fatigue-symptoms-by-65-percent-study-finds/.
Biological Research for Nursing (2009) Volume: 11, Issue: 2, Pages: 129-143.
J Endocrinol Invest. 2008 Jul;31(7):587-91.
com. “Long, low-intensity exercise may have more health benefits relative to short, intense sessions”
“Low-intensity exercise | Memorial Sloan Kettering Cancer ….” 13 Jul. 2021, mskcc.org/cancer-care/integrative-medicine/therapies/low-intensity-exercise.
Franklin BA, McCullough PA. Cardiorespiratory fitness: an independent and additive marker of risk stratification and health outcomes. Mayo Clin Proc. 2009 Sep;84(9):776-9. doi: 10.1016/S0025-6196(11)60486-2. PMID: 19720774; PMCID: PMC2735426.