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How much exercise do we need? The U.S. National Library of Medicine is clear about it: at least 30 minutes of aerobic exercise every day—that’s 210 minutes a week— and strength-training exercise twice a week.
Aerobic exercise is continuous physical activity using large muscle groups for a sustained period (a minimum of 10 minutes). “Aerobic” means “requiring oxygen;” it increases your body’s oxygen demand and your heart rate.
The Centers for Disease Control and Prevention (CDC) has its own thoughts on how much exercise we need for substantial health benefits: at least 150 minutes a week of moderate-intensity exercise. The CDC doesn’t mention how much exercise is required in strength training, but if you’re short on time, according to its recommendations, you can step it up and reap the benefits. The rule of thumb is that one minute of vigorous-intensity activity is about the same as two minutes of moderate-intensity activity.
How Much Exercise? More Opinions…
The American Heart Association (AHA) agrees with the CDC on how much time we should exercise but adds that how much exercise we get in a day includes nearly everything we do. Research has shown that you can divide your time into two or three smaller segments of 10 to 15 minutes each. “Physical activity is anything that makes you move your body and burn calories,” according to the AHA.
An editorial by Alex Mroszczyk-McDonald, MD, on the American Association of Family Physicians website echoes that advice.
“I tell patients if I could choose only one medicine from all the medicine in the world, it would be walking for 30 minutes five days a week to get a full 150 minutes,” Dr. Mroszczyk-McDonald wrote. “The best part is that research has shown that it doesn’t even need to be all at once. Five minutes in the morning, 10 minutes at lunch, and 15 minutes after dinner, and the patient still gets the same benefit.”
RESISTANCE EXERCISE: HOW IT HELPS
If you think “exercise” means walking, jogging, or other activities that get the heart pumping, you’re overlooking something important. When it comes to exercise, resistance training rarely gets the attention it deserves. The fact is that resistance training is equally as important as aerobic exercise. If you’ve ever pushed against a wall, lifted a dumbbell, or done push-ups, you’ve done resistance exercise.
Resistance training, also referred to as strength training, is deliberate exercise that challenges your muscles with stronger-than-usual counterforce. Muscles become stronger by using progressively heavier weights or increasing resistance. Resistance training helps you maintain or build strength, tones muscles, and can increase muscle mass and strengthen bones.
How Much Exercise? Still More Opinions
When the editors of Shape magazine addressed the question, they referenced a study published in Circulation that says 30 minutes of exercise per day isn’t enough. Their suggestion? Two hours a day, which the study maintains is how much exercise you need for your heart health. (Interestingly, the AHA says 40 minutes of aerobic exercise is how much exercise you need to lower your risk of heart attack or stroke and lower blood pressure and cholesterol.)
So… What’s the Answer?
On the other extreme, getting too much exercise can cause problems. “It is possible to get too much of a good thing,” according to Health.com. “It’s called overtraining, and it can show up as everything from chronic soreness to mood disturbances.”
If you’re exercising and not progressing, or if you feel worse after exercising than before, then it’s time to consult a physician about how much exercise you’re doing.
Otherwise, the smartest way to determine how much you should exercise is to pinpoint your goal. If you’re simply trying to maintain a healthy weight and stay fit, the CDC’s recommendation of 150 minutes a week will get the job done. If your goal is to do a full marathon (that’s 26.2 miles), it won’t. If you have weight-loss goals in mind, increase the intensity of your cardio—strive for upwards of 250 minutes of moderate-intensity exercise each week.
What’s the Difference Between Moderate-Intensity and Vigorous-Intensity Exercise?
You can adjust how much exercise you do in a set amount of time by varying the intensity of that exercise. The CDC gives us examples of exercise intensity:
SOURCES & RESOURCES
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- Walking briskly (3 miles per hour or faster, but not race-walking)
- Water aerobics
- Bicycling slower than 10 miles per hour
- Tennis (doubles)
- Ballroom dancing
- General gardening
- Race walking, jogging, or running
- Swimming laps
- Tennis (singles)
- Aerobic dancing
- Bicycling 10 miles per hour or faster
- Jumping rope
- Heavy gardening (continuous digging or hoeing)
- Hiking uphill or with a heavy backpack
Are you more into just walking for exercise? Go for it. “Walking and running provide an ideal test of the health benefits of moderate-intensity walking and vigorous-intensity running because they involve the same muscle groups and the same activities performed at different intensities,” according to Paul T. Williams, PhD, the study’s principal author and a staff scientist at Lawrence Berkeley National Laboratory.
Your Health and How Much Exercise
When embarking on any new exercise program and deciding how much exercise you should get, you may want to consult your physician or an experienced trainer. If you have any known chronic diseases—cardiovascular disease, diabetes, neurological ailments—it’s an absolute necessity to involve your physician.
Once you get the green light, how much exercise you need starts with your current fitness level.
HOW TO MAKE SURE YOUR EXERCISE IS AEROBIC
It’s important to measure your exercise intensity to be sure you’re performing aerobic exercise. There are three ways to do that:
- Check your heart rate. Moderate intensity is considered 50 to 70 percent of your heart-rate maximum. Vigorous intensity is considered 70 to 85 percent of your heart-rate maximum. You can calculate your heart-rate maximum by subtracting your age from 220. For example, if you’re 60, your heart rate maximum is 160 (220 minus 60).
- Use the Rating of Perceived Exertion (RPE). The Borg RPE scale is a tool that measures your intensity on a scale of 1 to 10, 1 feeling like you are lying in bed and 10 feeling like you are sprinting from a bear. Moderate intensity is often considered a 4 to 6, and vigorous intensity is often considered 7 to 9.
- Take the “talk test.” “If you’re doing moderate-intensity activity, you can talk, but not sing, during the activity. If you’re doing vigorous-intensity activity, you will not be able to say more than a few words without pausing for a breath,” explains the Centers for Disease Control and Prevention.
This article was originally published in 2018. It is regularly updated.