Whoop

Whoop is unusual among fitness wearables: it has no screen, shows no time, and focuses entirely on three metrics — recovery, strain, and sleep. This singular focus has made it the wearable of choice for serious athletes, military operators, and health-obsessed professionals.

## Core Metrics

**Recovery (0-100%):** Measured each morning based on previous night's sleep, heart rate variability (HRV), resting heart rate, and respiratory rate. A green score (67-100%) means your body is recovered and ready for hard training. Red (0-33%) means rest or light activity only.

**Strain (0-21):** Cardiovascular load measured throughout the day in real time. A strain of 15+ is a hard day; under 10 is recovery-level. Whoop recommends a target strain each day based on your recovery score.

**Sleep:** Whoop tracks time in REM, light, and deep sleep stages, plus sleep debt. It recommends a target sleep duration based on your strain and recovery goals, and detects sleep quality issues like caffeine interference and room temperature effects.

## AI Health Coaching

Whoop's AI analyzes behavioral patterns to surface insights: which behaviors correlate with your best recovery (consistent sleep timing, limited alcohol, cold exposure, meditation), which worsen it, and what your body's trends look like across months.

## Journal Feature

Daily behavioral data — alcohol consumption, stress, caffeine, naps, meditation, supplements — gets correlated with recovery scores over time. After 30+ data points, the AI surfaces your personal recovery correlations.

## Whoop Coach (AI Chat)

Recent versions include an AI assistant trained on Whoop's health data that answers questions about your trends, explains anomalies, and provides personalized recovery advice.

## Subscription Model

Whoop operates on a membership model: $239/year includes the hardware. No upfront device cost — the hardware is provided with membership. Higher tiers include advanced analytics and coach access.