What is sedentary behavior?

Sedentary behavior and physical inactivity are often confused, even though they are two distinct concepts. The distinction matters, since you can be sedentary while exercising, and vice versa.

Two different concepts, too often mixed up

Sedentary behavior refers to time spent sitting or lying down with very low energy expenditure: working while seated, watching TV, driving. It's measured independent of physical activity level otherwise. Physical inactivity refers to not reaching recommended physical activity levels, meaning 150 to 300 minutes of moderate activity per week according to the WHO. Someone can do an hour of intense exercise every day while remaining seated the rest of the time. They are then both “active” and “sedentary,” two realities that coexist without canceling each other out.

To measure these concepts, scientists use a unit called the MET (metabolic equivalent of task). One MET corresponds to the energy spent at rest, sitting quietly. Sedentary behavior is defined as any activity in a sitting or reclining position, while awake, that doesn't exceed 1.5 METs. Sleep therefore isn't part of it. Between 1.5 and 3 METs, activity is considered light: standing, cooking, walking slowly. From 3 to 6 METs, activity is moderate: brisk walking, easy cycling, active gardening. Beyond 6 METs, it is vigorous: running, sustained swimming, soccer. Standing at a counter is therefore not exercise, but it's already no longer sedentary behavior.

The World Health Organization's (WHO) guidelines, updated in 2020, don't stop at endurance. For adults, they call for 150 to 300 minutes a week of moderate activity, or 75 to 150 minutes of vigorous activity, or a combination of both. Muscle-strengthening exercises at least two days a week are added on top. After age 65, balance exercises are also recommended to prevent falls. For the first time, the WHO also explicitly recommends limiting sedentary time and replacing it with activity of any intensity, even light.

Concerning numbers, worldwide

At the global level, the WHO estimates that about 31% of adults, or 1.8 billion people, didn't reach the recommended physical activity level in 2022. This proportion has risen by 5 points since 2010, and could reach 35% by 2030 if the trend continues. Women are more affected than men (34% versus 29%), and the proportion rises markedly after age 60. Among teenagers, the situation is even more pronounced: about 8 in 10 don't move enough, according to the latest available data.

In France, adults spend on average about 7 hours a day sitting, according to the French food, environmental, and occupational health safety agency (Anses). According to the 2024 Santé publique France Barometer, 28% of adults aged 18 to 79 report spending more than 7 hours a day sitting. This proportion exceeds 40% among 18-29 year-olds, managers, and people who regularly work from home. On the physical activity side, about two adults in three meet the WHO guidelines: 76% of men and 61% of women in 2021. Anses estimates that, overall, 95% of French adults are exposed to a health risk, whether from insufficient physical activity, excessive sitting time, or both.

These figures conceal a social paradox. The most highly educated people and managers more often meet physical activity recommendations, thanks to sports in their leisure time, but they are also the most sedentary, because their work is done sitting in front of a screen. Conversely, people with modest incomes often move a lot at work, but engage in less leisure-time activity. Women are less active than men at every age, a gap researchers partly link to family responsibilities that still weigh more heavily on them.

In the United States, only 22% to 24% of adults meet both the aerobic and muscle-strengthening activity recommendations, according to federal CDC data. About one adult in four engages in no leisure-time physical activity at all. Sitting time is also high there: a study published in JAMA in 2019 (Yang et al.) put it at more than 6 hours a day among adults, up from previous years.

A phenomenon that comes at a high cost, to health and to healthcare systems

A landmark study published in The Lancet in 2012 (Lee et al.) attributed about 5.3 million deaths a year worldwide to physical inactivity, or nearly one in ten premature deaths. That's a scale comparable to smoking, even though the topic is far less present in public debate. The WHO now estimates that 4 to 5 million deaths a year could be prevented if the world's population were more active.

Physical inactivity raises the risk of numerous diseases: cardiovascular disease, type 2 diabetes, several cancers including colon and breast cancer, depression, and dementia. The cost to healthcare systems is considerable. In its 2022 global report, the WHO estimates that nearly 500 million new cases of chronic disease could occur between 2020 and 2030 because of physical inactivity, at a cost of about $27 billion a year.

Why is the problem getting worse? Our lifestyles have changed faster than our biology. Work has become mostly sedentary. Travel happens by car or public transit, leisure time is increasingly screen-based, and many everyday physical tasks have been mechanized. The human body, meanwhile, evolved over hundreds of thousands of years to walk and carry loads for several hours a day. Sedentary behavior therefore isn't a failure of individual willpower: it is, first and foremost, the product of an environment that no longer demands anything of the body.

Why this tool assesses both dimensions

This screening tool is based on weekly moderate and vigorous physical activity time, consistent with international guidelines. It draws on two reference questionnaires, the IPAQ and the GPAQ. It's a first step toward getting an objective picture of your situation, whether you consider yourself “active” or not, on a factor often underestimated compared to others like smoking or diet.

The IPAQ (International Physical Activity Questionnaire) was developed in the late 1990s by an international consortium of researchers and validated in 12 countries. It is widely used in research in Europe, including France. The GPAQ (Global Physical Activity Questionnaire) was developed by the WHO for its worldwide surveillance surveys. It distinguishes activity at work, during travel, and during leisure time, which makes it suited to countries where physical activity mostly comes from manual labor. Both questionnaires also include a question on time spent sitting during a typical day.

These tools share a common limitation: they rely on self-reports. Studies comparing responses with accelerometer measurements show that many people overestimate their activity and underestimate their sitting time. To refine your answer, take the time to review a typical week, day by day, counting commutes, work, leisure, and everyday tasks. The result isn't a judgment. It simply shows where you stand relative to the benchmarks, so you can decide what you'd like to do.

To estimate your own sedentary behavior level, take the “What is my physical activity level?” test.