Lancet Study: 1 in 4 Teens Worldwide Reported No Active Day in a Week, and the 15-Year Trend Is Flat

Roughly 240 million adolescents reported zero days of at least 60 minutes of moderate-to-vigorous exercise in the previous week, according to a study published Nov. 4 in The Lancet Global Health. That is 24.9% of 11-to-17-year-olds, based on 2025 estimates.

The finding that stands out is the flat line. The share of adolescents reporting fewer than seven active days a week has not changed since 2010.

What the study measured

The analysis, led by Tessa Strain, pooled 389 population-based surveys with 3.2 million participants from 140 countries. The authors say that covers 59% of the world's adolescents.

An "active day" is one with at least 60 minutes of moderate-to-vigorous activity. That includes sports, brisk walking, cycling to school or anything else that raises heart rate or breathing.

The numbers for 2025:

• Adolescents averaged just 2.7 active days per week.
• Only 14% were active all seven days.
• No country or region is on track to meet the target adopted by WHO member states in 2018: cut adolescent physical inactivity by 15% by 2030, measured against 2010.

The data come from self-reported surveys. NPR noted that researchers would prefer wearable trackers but they would be too costly at this scale, so most surveys ask a simple question: on how many of the past seven days were you active for an hour?

Girls and the income gap

Girls trailed boys in almost every country and every WHO region. About 28% of girls reported no active days, versus 22% of boys. Only 11% of girls were active every day, versus 17% of boys. Girls averaged 2.4 active days a week; boys averaged 3.

Wealth matters too. In high-income Western countries, Central and Eastern Europe, Central Asia, East Asia and the Pacific, adolescents averaged about four active days. Between 6.9% and 7.7% reported none.

In lower- and middle-income regions, including Latin America and the Caribbean, the Middle East and North Africa, South and Southeast Asia, Oceania and Sub-Saharan Africa, the average was about two days. Between 22.7% and 33.1% reported none.

Finland, Canada and Serbia posted the highest averages, 4.5 to 4.8 active days. Cambodia, Jordan and Madagascar posted the lowest, 1.7 to 1.9. In the UK, 17% of adolescents hit the daily threshold: 21% of boys and 13% of girls.

What WHO says should change

Fiona Bull, head of the WHO's physical activity unit and a study co-author, called the results "disappointing." "The trend over the last 15 years is flat," she said. "Business as usual will not change these trends."

WHO Director-General Tedros Adhanom Ghebreyesus put the prescription bluntly: "The answer is not to tell adolescents to try harder. It is to build schools, streets and communities where moving, playing and being active is safe, easy and normal."

The study's authors call for "targeted, context-specific approaches" aimed at the least active teens, plus population-wide action on the "social, cultural, and environmental barriers" that keep girls in particular on the sidelines.

Outside researchers point the same way on environment. Andrea Ramirez Varela, an epidemiologist at the University of Texas Health Science Center in Houston, told NPR that physical activity is "an issue of opportunity." She said many cities, including in Latin America, are not designed to be walkable. The study did not break out urban and rural adolescents. Ramirez Varela said some research suggests rural teens in lower-income countries move more, often out of necessity.

Why the stakes extend past adolescence

Solveig Cunningham, a global health researcher at Emory University, told NPR that habits set in the teen years tend to carry forward: "If your baseline is zero days of physical activity, that's going to be your baseline as you go into adulthood."

Indian physicians quoted by Times Now say inactivity in adolescence can contribute to insulin resistance, excess abdominal fat and unhealthy cholesterol and blood pressure. Dr. Ashok Kumar Jhingan of BLK-Max Super Speciality Hospital in Delhi said the metabolic changes can begin in the teen years even if serious complications show up later.

The same reporting carries a caveat: inactivity alone does not mean a teenager will develop type 2 diabetes. Genetics, diet and body composition also play a role.

The WHO says physical inactivity is a leading risk factor for noncommunicable diseases, which account for 75% of deaths globally.

What comes next

The 2030 deadline is a little over four years away. The report projects adolescent inactivity will stay largely unchanged through the decade without faster action.

The WHO has not published a cost for the schools, streets and communities Tedros describes. Nor has it named which governments have committed to building them. Bull's own statement leaves the central question open: after 15 years of flat numbers, what, specifically, replaces business as usual?