Is It the Duration or the Intensity of Exercise That Protects Health?

A new study has revealed that not only “how much we move” but also the intensity of movement may be decisive for health. In a large-scale study using UK Biobank data, researchers evaluated the relationship between physical activity intensity and chronic disease risk. The study analyzed the health outcomes of more than 96,000 people with physical activity data and approximately 376,000 individuals who reported their own exercise levels.

The results showed that, regardless of the total amount of exercise, individuals who did a higher proportion of vigorous physical activity had a markedly lower risk of eight major chronic diseases, including cardiovascular disease, atrial fibrillation, type 2 diabetes, chronic kidney disease, dementia and chronic respiratory diseases. In particular, even vigorous exercise making up only a small part of total activity was shown to provide notable protective effects. The researchers emphasized that some health benefits became apparent even at a vigorous activity level of around 5%.

The study also revealed that, for dementia and inflammatory diseases, exercise intensity may be a stronger protective factor than total exercise duration. In contrast, for metabolic diseases, both intensity and the total amount of movement mattered together.

Conclusion: Short but vigorous physical activity may provide stronger health benefits than long, low-intensity exercise; therefore, intensity, not just duration, is becoming a goal in exercise.

Source: "Volume vs Intensity of Physical Activity." European Heart Journal. Published: April 2, 2026.