HIIT alternates short, all-out bursts with rest or low-intensity periods. A typical session lasts 20-30 minutes but produces metabolic effects that outlast a 60-minute steady-state session.

The key mechanism is EPOC — excess post-exercise oxygen consumption. After a HIIT session, your body continues burning calories at an elevated rate for up to 24 hours as it repairs tissue and replenishes energy stores.

HIIT also improves insulin sensitivity, boosts VO2 max and preserves lean muscle mass better than steady-state cardio alone. For time-poor members, it is the highest-leverage training modality available.

Our recommendation: 2-3 HIIT sessions per week, with at least 48 hours between them. Pair with strength training and one low-intensity session for a complete programme.