How Much Exercise Do We Need?

by Sydnee Mostak

We all know about the importance of exercise. It’s drilled into us by social media, TV, and magazines. What you might not know is, how much (or how little) do you actually need? And why is it SO important? Let’s take a moment to uncover some of that .

According to the Physical Activity Guidelines for Americans, adults should acaccumulate at least 150-300 minutes of moderate-intensity or 75-150 minutes of vigorous-intensity activity per week, plus at least 2 days of strength training weekly. That shakes out to a minimum of just 30 minutes per day of moderate-intensity activity, 5 days per week. Cool. What does that mean?

Moderate-intensity activity is something that gets your heart rate above normal, but you can still have a conversation through your breathing. A brisk walk is easy and accessible to many, so it’s a preferred example. Dancing, playing tennis, and bike riding could also fall into this category. Vigorous-intensity is what many people think of when they think of exercise. Jogging, jumping rope, high-intensity interval workouts, even swimming. These things get you a little more breathless, and it would be hard to have a good conversation amid these activities.

During your 2 strength training workouts, it’s recommended that you work all your major muscle groups with at least 1 set of 8-12 repetitions. Major muscle groups include legs, hips, abs, arms, chest, back, and shoulders. 2-3 sets is better for muscle growth and maintenance. You don’t have to limit yourself to 2 days.

Many people do strength training more frequently, allowing them to break the workouts into smaller units, working fewer muscle groups per session. It comes down to your goals (do you want to build muscle, get strong, or just maintain current function?) and your available time. Regardless, at the very least, you want to be doing some sort of strength training twice per week.

One of the other recommendations is to move more throughout the day. As Americans, we sit an awful lot! Between work, commutes, and the end-of-day screen time or reading time we use to unwind, there are lots of opportunities for stillness.

A recent study looked at 18 review articles related to prolonged sitting, or sedentary time, and the various effects it can have. It was found, through very mixed evidence, that more sedentary time might be associated with poorer quality of life, decreased cognitive function (hello, brain fog), and increased risk of depression and heart disease. Breaking this sedentary time up, or getting up and doing something for a few minutes when you’re bound to a chair for awhile, might not count as exercise, but it can reduce your risk of these complications.

Although one study supports adding what they call “exercise snacks” to the day. These are very brief, intense bouts of exercise. Like climbing stairs or sprinting for 3 minutes. They serve the dual purpose of breaking up sitting time AND improving fitness. Win-win.

What’s the point of exercise, though? Is this just for weight loss? NOPE. This is for your health! Regular exercise, specifically exercise at this recommended amount, significantly reduces your risk of heart disease, high blood pressure, diabetes, some cancers, osteoporosis, and even cognitive decline. It also increases your functional lifespan, extending your ability to perform activities of daily living (think, carrying and putting away groceries) and reducing your risk of falls and frailty as you age, while improving your ability to recover from those things, should they occur.

Generally, the closer you get to the upper recommended amount of physical activity, the greater the health benefit. So, to answer the questions posed in the beginning, while any physical activity is better than none, more is better, without going overboard. If you want to exercise for 10 minutes a day, you’ll be doing better than if you do nothing at all; but you’ll get the most benefit from accumulating an hour a day. Do what fits in your life, even if that’s a few 10-15 minute sessions throughout the day instead of trying to find a whole hour to set aside. 

However you fit it in your day, and whateer intensity you choose, regular exercise is imperative for good health for all ages. This includes cardio and strength training. Sit less and engage in exercise that makes you feel good to decrease your risk of chronic disease and maximize your functional lifespan.