This calculator is for general information and education. It is not medical advice and does not replace the judgment of a doctor, nurse or pharmacist who knows the full clinical picture.
A simple test of everyday fitness
The six-minute walk test measures how far you can walk on a flat, hard surface in six minutes. It reflects the combined work of the heart, lungs, muscles and circulation during an activity close to daily life. Doctors use it for chronic lung disease, heart failure and pulmonary hypertension, to judge fitness before surgery, and to measure progress in rehabilitation.
How the test is done
The American Thoracic Society published standard guidelines in 2002, updated with the European Respiratory Society in 2014:
- A flat indoor corridor of 30 m (100 ft), marked every 3 m, with cones at each end.
- The patient walks back and forth as far as possible, at their own pace, and may slow down or rest.
- Standard phrases of encouragement are given each minute.
- Heart rate, oxygen saturation and breathlessness are recorded before and after.
Predicted distance
For healthy adults aged 40 to 80, Enright and Sherrill proposed in 1998:
Men: 7.57 × height (cm) − 5.02 × age − 1.76 × weight (kg) − 309 m
Women: 2.11 × height (cm) − 2.29 × weight (kg) − 5.78 × age + 667 m
The lower limit of normal is about 153 m below the prediction for men and 139 m for women.
Example
A man aged 60, 5 ft 9 in (175 cm) tall and 180 lb (81.6 kg), walks 1,500 ft (457 m):
- Predicted: 7.57 × 175.3 − 5.02 × 60 − 1.76 × 81.6 − 309 ≈ 573 m (1,880 ft)
- Percentage of predicted: 457 ÷ 573 ≈ 80%
- Lower limit of normal: about 420 m, so his result is within the normal range.
Interpreting changes
- A change of about 25 to 33 m is the smallest difference patients notice in chronic lung disease.
- In COPD, a distance under 350 m is linked with a higher risk of hospitalization and death and is used in the BODE index.
- A drop in oxygen saturation of 4 points or more during the test is clinically important.
Limits
Prediction equations come from specific populations and vary up to 100 m between studies. Practice matters: a second test on the same day is often 20 to 30 m longer. Height, leg length, motivation, pain and arthritis all affect the result, so use the trend in the same person over time rather than a single comparison.