HIIT (High-intensity interval training)

HIIT alternates short bouts of near-maximal effort with periods of low-intensity recovery, typically over 10–30 minutes total. The high-intensity intervals stress cardiac output and mitochondrial function, driving rapid gains in VO2max, insulin sensitivity, and stroke volume. Compared with steady-state cardio, HIIT delivers similar or greater cardiorespiratory adaptations in less time, making it a time-efficient longevity intervention when balanced with lower-intensity aerobic work.