Not getting enough exercise is a global problem.

Around the world, at least 1.4 billion adults are putting themselves at risk for chronic disease because of their low levels of physical activity, according to a new World Health Organisation report published in the Lancet Global Health journal.

The WHO's recommended physical activity guidelines are fairly close to those set by the Centers for Disease Control: healthy adults should get at least two and half hours of moderate-intensity activity – or 75 minutes of vigorous-intensity activity – per week, plus at least two muscle-strengthening days.

The new report found that around the world, 32 percent of women and 23 percent of men don't get enough exercise, even when accounting for time spent walking or biking to work and physical activity on the job.

(The CDC's measurements of physical activity levels in the US don't count commuting or activity at work, since those aren't shown to have the same improvements on health as exercise during leisure time.)

Wealthy countries are particularly exercise deficient, according to the WHO: close to 40 percent of US adults and 36 percent of UK adults are too sedentary.

A 'grave concern'

These rates of exercise haven't improved since 2001, the WHO report found. They even got worse in wealthy countries like the US and Germany, Latin American nations like Brazil and Argentina, and in various parts of the Caribbean.

"Unlike other major global health risks, levels of insufficient physical activity are not falling worldwide, on average, and over a quarter of all adults are not reaching the recommended levels of physical activity for good health," lead study author Dr. Regina Guthold said in a statement.

This growing inactivity is of "grave concern," the American Heart Association said in a statement. That's because a lack of exercise increases one's risk of heart disease, stroke, high blood pressure, cholesterol, and body weight.

Around the world, there's a lot of variation in physical activity levels. Only 6 percent of residents of Uganda and Mozambique were too sedentary, the report found, making those countries the most active in the world.

In Kuwait, Saudi Arabia, American Samoa, and Iraq, more than 50 percent of adults don't get enough exercise. In general, women are far less active than men, except in east and southeast Asia.

How to meet fitness guidelines

Not getting enough exercise increases risk for cardiovascular disease, type 2 diabetes, dementia, and various cancers.

To meet the minimum fitness guidelines from the CDC and WHO, you should put in an average of about 30 minutes per day. Five days of moderate-intensity aerobic exercise – like a 30-minute brisk walk or a casual bike ride – is enough to meet the aerobic guidelines.

Then two days should also include resistance training that involves weights or body-weight exercises, since those activities are the best ways to strengthen bones and muscles.

If that sounds like a lot, you can get your weekly dose of exercise faster by doing vigorous exercise like running or swimming – anything that gets your heart pumping. It takes just 75 minutes of that type of physical activity each week to meet the guidelines.

If you live a sedentary life, you may want to get more exercise than the minimum guidelines call for.

Sitting all day basically causes gradual damage to your heart, and most studies suggest that the basic fitness guidelines aren't enough to offset the harms of sitting.

To do that, you essentially need to do double the recommended minimum and get between 60 and 75 minutes of moderate-intensity exercise per day.

That may sound like a lot. But working out is one of the most effective ways to transform your physical and mental health.

When you look at the benefits of exercise, which include significantly reducing the risk of various diseases, keeping your mind sharp as you age, and fighting depression and anxiety, it's worth the time.

This article was originally published by Business Insider.

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