Tool / wearable
WHOOP
Last updated Sat May 30 2026 00:00:00 GMT+0000 (Coordinated Universal Time)
What it does
WHOOP is built around three daily numbers:
- Recovery score (0–100%): combines overnight HRV, RHR, sleep duration/quality.
- Strain score (0–21): cardiovascular load accumulated through the day, including both exercise and life stress.
- Sleep score: contribution to recovery from sleep.
Strengths
- Continuous wear (no screen, no UI distraction).
- Excellent recovery-based training-load model.
- Strong HRV-trend tracking compared with most wrist devices.
- Subscription model means free firmware/hardware upgrades.
- Decent journal feature for correlating recovery with behaviours.
Trade-offs
- Cost-over-time: subscription means you don’t own the device.
- No screen / smartwatch features.
- Heart-rate signal from wrist is less accurate than chest strap during high-intensity exercise.
- The "recovery score" is a black box; useful as trend but not scientifically validated as a definitive recovery indicator.
Best for
- Athletes managing training load.
- Adults tracking HRV trends over months.
- People wanting recovery-guided training decisions.