How POTS Check Works

The NASA Lean Test Protocol

POTS Check guides you through the NASA Lean Test, a clinically-recognized screening protocol that measures your heart rate response when transitioning from lying down to standing.

Baseline Phase (5 minutes)

Lie flat on your back and remain still while your Apple Watch measures your resting heart rate. This establishes your baseline for comparison.

Stand Transition (~20 seconds)

When prompted, stand up and lean against a wall with your feet about 6 inches away. The app uses motion sensors to verify your posture.

Standing Phase (10 minutes)

Remain standing against the wall while your heart rate is continuously monitored. You can log symptoms and optionally record blood pressure readings.

Recovery Phase (1 minute)

Sit or lie down while your heart rate is measured to see how quickly it returns to baseline. This phase is optional.

Learn More About the NASA Lean Test

What You'll Get

Heart Rate Analysis

See your baseline heart rate, maximum standing heart rate, and the change (ΔHR) with clear visualization.

Age-Based Interpretation

Results are analyzed using age-appropriate criteria: 40+ bpm for ages 13-19, 30+ bpm for adults 20+.

Symptom Timeline

Any symptoms you logged during the test are recorded with timestamps for comprehensive reporting.

Posture Quality Score

See how well you maintained proper positioning during the test, which affects result reliability.

PDF Report

Generate a professional report to share with your healthcare provider, including all test data.

Test History

With a Secure Account, track trends across multiple tests to identify patterns over time.

Understanding Your Results

Before You Test

For the most accurate results, follow these preparation guidelines.

Timing

Avoid caffeine, alcohol, and heavy meals 4 hours before
Avoid nicotine/vaping 2 hours before
Avoid exercise 2 hours before
Test at the same time of day for consistency

Environment

Find a quiet, comfortable space
Have a wall nearby for support during standing
Ensure stable room temperature
Have a place to lie down comfortably

Equipment

Apple Watch (30%+ battery, worn snugly)
iPhone with POTS Check installed
Optional: Blood pressure cuff
Comfortable, non-restrictive clothing

Two Ways to Use POTS Check

Choose the option that's right for you. Both are completely free.

Guest Mode

Perfect for trying it out

No account required
Single test at a time
Data stored in memory only
PDF export available
Data cleared when you end session

Secure Account

For ongoing monitoring

Unlimited test history
Data encrypted on device
Trend charts and analysis
Health Profile import
Professional PDF reports

Safety First

⚠

Stop the Test Immediately If You Experience:

Severe dizziness or feeling like you might faint
Chest pain or pressure
Severe shortness of breath
Vision changes or near-blackout
Irregular heartbeat that feels abnormal
Severe headache or nausea

Always test in a safe environment where you can sit or lie down immediately if needed. If symptoms persist after stopping, seek medical attention.