High-intensity interval training is trendy right now – and for good reason. HIIT workouts are a time-expedient way to get into tip-top shape and enjoy the many health benefits that exercise offers. When you have limited time to work out, high-intensity interval training is the most time-expedient way to get results. Studies show HIIT workouts as short as 10 minutes can deliver health and fitness benefits, comparable or even greater than longer periods of moderate-intensity exercise. With so much emphasis on pushing your body to the point of breathlessness during HIIT sessions, you might wonder whether the more laid-back approach, low-intensity exercise offers any health benefits at all.
Are There Health Benefits to Low-Intensity Exercise?
Have you ever been injured or recently ill and had to lighten up on your workouts? Well, there’s good news. You can get benefits even if you dial back the intensity of your training. First, don’t confuse low-impact with low-intensity. With low-impact workouts where both feet don’t leave the ground at the same time, you can still exercise a high intensity.
Low-intensity workouts are ones where you intentionally don’t elevate your heart rate. They correspond to MET (metabolic equivalents) in the range of 2 to 3, the equivalent of taking a leisurely walk, slow pedaling on a bike, or light gardening. During low-intensity exercise, you can easily carry on a conversation. These are exercises that won’t leave you breathless or sweating and ones that many people find enjoyable – but do they offer health benefits?
If you subscribe to the idea of “no pain, no gain,” you might think low-intensity exercise is more for relaxation than for health or fitness benefits. However, studies suggest that even light activity that doesn’t cause you to break a sweat has health benefits as well, especially with respect to metabolic health.
What a Study Showed
Research carried out by researchers from Masstricth University in the Netherlands compared the impact of three different exercise regimens on insulin sensitivity and blood lipids. One group exercised intensely for an hour each day but sat for an additional 13 hours. A second group sat for 6 hours daily, walked leisurely for 4, and stood for 2 hours. A third group did no exercise all day. When they measured insulin sensitivity for the three groups, the group that did 4 hours of low-intensity exercise showed greater improvements in insulin sensitivity than did the participants that exercised vigorously for an hour. They also showed greater improvements over the group that did no exercise. Also, lipid levels improved more in the group that was active at a low level throughout the day relative to the group that did the high-intensity workout followed by sitting.
In many ways, the results of this study aren’t surprising. When you do a high-intensity workout for an hour your insulin sensitivity improves in response to that workout, but if you spend the rest of the day sitting, insulin sensitivity will drop because you’re not moving around. In contrast, the group that walked for 4 hours throughout the day and stood more will continue to show improvements in insulin sensitivity since they’re spending a greater portion of their day not being sedentary. These findings go along with studies that show how damaging prolonged sitting can be to insulin sensitivity and metabolic health.
Low-Intensity Exercise: Good for Metabolic Health but What about Heart Health?
It’s important to note that this study didn’t look at the cardiovascular benefits of low-intensity exercise versus high-intensity exercise. A high-intensity workout boosts your heart rate more, improves aerobic capacity, and makes your cardiovascular system more efficient relative to walking at a leisurely pace. That’s important since aerobic capacity is linked with mortality. A study showed that among middle-aged men, low aerobic capacity is second only to smoking as a risk factor for early death. Low-intensity exercise throughout the day will have limited impact on your aerobic capacity since it doesn’t elevate your heart rate enough. That’s where high-intensity exercise excels. As the researchers in the study point out, low-intensity exercise has metabolic benefits as long as you burn an equivalent number of calories to what you would burn during a higher intensity session. So, you’ll need to exercise longer to get benefits.
This study also shows the importance of moving throughout the day. In the study, the group that received the most benefits walked at a low intensity for 4 hours daily and stood for 2 hours. In contrast. the high-intensity group exercised for an hour and then sat. Research shows that sitting for long periods of time is bad for your health. In fact, a study published in the American Journal of Preventive Medicine found that sitting for long periods of time contributes to 430,000 deaths worldwide. That’s an astounding number! The biggest strength of low-intensity exercise is it doesn’t poop you out and you can do it longer and continue to do it throughout the day.
Keep Your Training in Balance
The reality is you should do both types of training. High-intensity workouts have enormous cardiovascular benefits while low-intensity training has fewer cardiovascular benefits but can improve insulin sensitivity. For example, studies show that taking a 10-minute walk after a meal helps with blood sugar control in diabetics. That’s because movement improves insulin sensitivity.
Plus, there’s a lot to be said for the stress relief aspects of low-intensity exercise. Low-intensity exercise doesn’t have to be walking. It includes structured activities like yoga and tai chi or doing light outdoor activities like gardening. So, when you’re exhausted from too many high-intensity workouts and your body needs a break, don’t be afraid to dial back the intensity for a day and let your body recover. Just as importantly, keep your body moving throughout the day by walking around, stretching, and fidgeting when you sit. All forms of movement have health benefits – so take advantage of your body’s ability to move as often as you can.
ScienceDaily.com. “Long,low-intensity exercise may have more health benefits relative to short, intense sessions”
ScienceDaily.com. “Low physical capacity second only to smoking as highest death risk”
Medical News Today. “Prolonged sitting: ‘Exercise does not offset health risks,’ says AHA”