# HIIT (High-intensity interval training)

HIIT (high-intensity interval training) alternates short bursts of near-maximal effort with periods of easy recovery. A session usually runs 10 to 30 minutes total. The hard intervals stress your heart's output and your mitochondria. That drives fast gains in VO2max, insulin sensitivity, and stroke volume (how much blood your heart pumps per beat). Compared with steady-state cardio, HIIT delivers similar or greater fitness gains in less time. That makes it a time-efficient longevity tool, as long as you balance it with some lower-intensity aerobic work.

## Sources

- Gibala MJ, Little JP, Macdonald MJ, Hawley JA. (2012). Physiological adaptations to low-volume, high-intensity interval training in health and disease. Journal of Physiology. https://doi.org/10.1113/jphysiol.2011.224725

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_Canonical: https://longevity-switzerland.com/en/glossary/hiit · Part of Longevity Cities · Updated 2026-06-22_