What Qualifies as Low-Intensity Cardio?
Low-intensity or light cardio refers to any physical activity that raises your heart rate without skyrocketing it. A good rule of thumb: You should be able to talk or sing while exercising, Meagan Wafsy, MD, of Massachusetts General Hospital told the American Heart Association.
For comparison, during moderate-intensity exercise, you'll be able to speak but not sing, and when working at a high-intensity, you won't be able to speak in full sentences. Keep in mind, though, that low-intensity doesn't always equal low-impact cardio, which refers to activities that don't put stress on your joints. A workout certainly can be both, but it doesn't have to be.
Potential low-intensity (and low-impact) cardio options include walking, yoga, tai chi, riding a bike and swimming, provided that you don't go too fast or too hard. While you're not pushing yourself to your limit, the trade-off is that you're doing it for a longer period of time.
Does Low-Intensity Cardio Burn More Fat?
Cardio machines have long indicated when a person was in the "fat-burning zone," which supposedly correlated with low-intensity exercise. However, low-intensity cardio doesn't necessarily lead to higher fat-burning potential, according to the National Academy of Sports Medicine.
Although your body uses a higher percentage of fat as fuel when you're exercising at a low intensity, you burn more calories overall when exercising at a higher intensity. And more calories burned means more overall fat loss.
5 Benefits of Low-Intensity Cardio
1. Improved Insulin Sensitivity
Just one session of low-intensity exercise (50 percent VO2 max) can improve a person's insulin sensitivity in people with diabetes, concluded a study published in September 2013 of Diabetes Care. Insulin sensitivity refers to how effectively the cells in your muscles are able to use insulin to use glucose for energy, according to the American Diabetes Association.
2. Better Balance for Older Adults
Low-intensity exercise can help improve balance and increase leg strength in adults age 65 to 85, according to a review published in October 2015 in Sports Medicine. Additionally, more than half of the studies reviewed supported the conclusion that low-intensity exercise decreases the risk and frequency of falls in older adults, which is a major cause of injuries, including bone fractures.
3. Decreased Waist Circumference
If you hate high-intensity exercise but want to lose inches, here's good news: Low-intensity exercise decreases waist circumference just as effectively as high-intensity exercise, concluded a study published in March 2015 in the Annals of Internal Medicine.
Researchers assigned participants to four groups, one of which was 30 minutes of low-intensity exercise. All of the groups, except the control group that didn't do anything differently, lost an average of four centimeters from their waist.
4. More Enjoyment While Exercising
High-intensity exercise gained popularity because it takes less time to complete. However, the best type of exercise is the one that you're going to stick to — and that just might be lower-intensity options, according to research published in December 2015 in the Journal of Sports and Science in Medicine.
In the study, the researchers found that people who participated in lower-intensity, steady-state cardio enjoyed the time they spent exercising more than those who did a Tabata workout (a type of high-intensity interval training or HIIT).
And that means you're less likely to quit your workout regimen. A December 2015 review published in Sports Medicine - Open supports the idea that low-intensity exercise results in better exercise adherence — meaning you're more likely to stick with it.
5. Opportunity to Rest and Recover
Even if you do love to hit up HIIT class, you can't go hard all the time. Consistently pushing yourself to your limits every single time you hit the gym is a recipe for overtraining, which can result in injury and a weakened immune system, according to a September 2012 review article from Sports Medicine.
That's why it's a good idea to incorporate at least one low-intensity active recovery workout into your weekly routine. These sessions can help reduce inflammation and stiffness, increase blood flow, improve mobility and flexibility and clear built-up lactic acid. And if you're lifting weights or training for a race, your rest and easy days are when your muscle repair and get stronger.
How Much Low-Intensity Cardio Should You Do?
Ideally, you're doing at least 150 minutes of moderate-intensity aerobic activity each week (or 75 minutes of high-intensity cardio), according to the Physical Activity Guidelines for Americans.
Where low-intensity exercise fits in that is up to you. Maybe it's one 60-minute hike each week on your active recovery day. Or perhaps you want to take a 30-minute walk during your lunch break every day. You could even aim to hit 10,000 steps a day and incorporate your low-intensity cardio throughout your day.