VO₂max.io

HIIT twice a week

HIIT twice a week: two 20-minute sessions

Two short sessions a week, about 20 minutes each. Session A uses longer intervals, session B shorter ones. Pick the session and press Start.

HIIT twice a week timer

Warm-up
0:00
Next up
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Work intervals

Beeps 3 seconds before each change. Keeps the screen awake where the browser allows it.

Heart problems? Check with a doctor before hard intervals or a maximal test if you have heart problems. Stop if you feel chest pain or dizziness.

The program

DaySessionTime
Day 1 (e.g. Tuesday)A: 4 min warm-up, 3 × (3 min hard, 2 min easy), 3 min cool-downabout 20 min
Day 2 (e.g. Friday)B: 4 min warm-up, 12 × (30 s hard, 30 s easy), 4 min cool-downabout 20 min

This program is our suggestion, not a study protocol. The idea of hard intervals twice a week comes from the Generation 100 study, where people aged 70–77 did interval sessions twice a week for five years. Leave at least one day between the sessions. Walking or easy cycling on other days helps too.

Want more? Add a Norwegian 4×4 or follow the 8-week plan.

More interval tools

Beep & Cooper test calculator

Your VO₂ max and rating for age and sex.

Interval timer

Set your own work, rest and rounds.

Norwegian 4×4

4 × 4 min hard, 3 min easy.

30/30 intervals

Run 30 s, walk 30 s.

Tabata 20/10

8 × 20 s all-out, 10 s rest.

HIIT exercises at home

No equipment, with timer.

FAQ

Is twice a week enough?

Twice a week is a good start for most people. Studies with more sessions usually show bigger gains.

Which activity?

Anything that makes you breathe hard: running, cycling, rowing, fast uphill walking.

Sources

  1. Stensvold D, Viken H, Steinshamn SL, et al. Effect of exercise training for five years on all cause mortality in older adults — the Generation 100 study: randomised controlled trial. BMJ 2020;371:m3485. doi:10.1136/bmj.m3485 (free: PMC7539760)

Last updated: October 24, 2026. Written with AI assistance.