Too Hot to Run? How Warmer Days Shape Teenagers’ Movement

Does the thermometer influence how our youth move? A study in Spain and the Netherlands analyzes the link between heat and physical activity in adolescents.

Reading time: 2 minutes.

As the world gets warmer, our environment may be changing the way young people move. A mild, sunny day can make walking to school, cycling to a friend’s house, or spending time outdoors feel more appealing. But when temperatures keep rising, does warmer weather still encourage teenagers to be active, or does it eventually become a barrier?

Physical activity during adolescence is essential for physical health, mental well-being, and the development of habits that can last into adulthood

This question matters. Physical activity during adolescence is essential for physical health, mental well-being, and the development of habits that can last into adulthood. Yet many young people do not reach the recommended activity levels set by the World Health Organization. At the same time, climate change is making warmer days and heat extremes more common. Understanding how temperature affects daily movement is therefore not just a lifestyle question, but also a public health and climate adaptation one. In our study of teenagers in the Netherlands and Spain, we found that warmer days were linked to more light and moderate physical activity, such as walking and cycling, but not to more vigorous activity, such as running or intense sports.

Beyond Questionnaires: Tracking Movement with Wearable Tech

We looked at how everyday temperature exposure was related to the time adolescents spent being physically active at different intensity levels: light (like yoga and walking), moderate (like cycling), and vigorous (like playing soccer). We used data from two European cohorts: The Generation R Study in the Netherlands and the INMA Project in Spain.

Warmth may invite adolescents to move more, to walk, cycle, stroll, play casually, or be outdoors, but it does not seem to push them towards higher-intensity activity such as running, fast sports, or strenuous exercise

Instead of relying on questionnaires, we used wrist-worn motion sensors, which is wearable technology that records movement throughout the day. We also linked each teenagers’ activity data to temperature levels at their home address. Importantly, we did not only look at the temperature on the day of the activity, but we considered the temperatures of the previous days, because yesterday’s weather may still influence how much someone feels like moving today.

Warmth Encourages Light Activity…

The main finding was clear: adolescents spent more time in light and moderate physical activity on warmer days. In the Dutch cohort, a 5 ºC increase in temperature was linked to around 11 extra minutes of light activity and 5 minutes of moderate activity per day. In the Spanish cohort, the increases were even larger: around 16 minutes of light and 14 minutes of moderate activity. These may sound like small numbers, but when it comes to daily movement, small increases matter and can contribute to meaningfully healthier routines.

…But it Doesn’t Boost Vigorous Activity

But here comes the interesting part: warmer days did not lead to more vigorous activity. This is the paradox at the heart of the study. Warmth may invite adolescents to move more, to walk, cycle, stroll, play casually, or be outdoors, but it does not seem to push them towards higher-intensity activity such as running, fast sports, or strenuous exercise.

Several possible explanations

There are several possible explanations. Light and moderate activities are easier to fit into daily life and are often linked to being outside: walking to school, cycling, meeting friends, or spending time in parks and streets. These activities may feel more attractive when the weather is pleasant. Vigorous activity, on the other hand, may be more structured, such as organized sports or training sessions, which could be less dependent on the weather.

We had limited data from very hot summer days, which means we may not have captured the conditions under which heat becomes a stronger barrier. This is an important point for future research

Another possibility is more biological: as temperatures rise, higher-intensity exercise becomes less comfortable and may place more strain on the body. At some point, heat may stop being a motivator and start becoming a warning signal.

Our study did not find a clear temperature threshold where activity started to decline. One likely reason is that the temperatures observed in our data were moderate. We had limited data from very hot summer days, which means we may not have captured the conditions under which heat becomes a stronger barrier. This is an important point for future research, especially as climate change increases the frequency and intensity of heat events.

Building Climate-Adapted Environments for Healthy Teens

So, what does this mean in practice?

1. Temperature should be considered when designing strategies to promote physical activity among young people. A campaign encouraging teenagers to move more may work different in spring than during a heatwave.
2. Schools, sport clubs, and city councils need to think seriously about climate-adapted activity environments. Shade, trees, drinking water, cooler playgrounds, safe cycling routes, and access to indoor or shaded sports spaces should not be luxuries. They are part of the essential infrastructure needed to help adolescents stay active safely.

Warmer days may encourage teenagers to engage in more light and moderate physical activity, but if we want young people to remain active, healthy, and protected as the climate changes, we need to plan for the heat. Supporting active lifestyles in a warming world means creating environments where all adolescents can move comfortably and safely.