6-Minute Walk Test
What is it?
This is a simple walking test that will provide your physician with an indication of your exercise capacity and general health status. It is measured by the distance you are able to walk in six minutes.
What to expect?
This test requires only simple test equipment and can be performed wherever there is sufficient space. Two markers should be set on the floor 100 feet apart in an obstacle-free corridor. You will be asked to walk back and forth between the two markers for a total of six minutes. You will be walking by yourself. You will make the turn at each end of the walking course by circling around the far side of the marker rather than turning abruptly.
If you are oxygen-dependent then you should expect to have supplemental oxygen during the test, but you will be expected to carry or pull your oxygen without assistance. If you require a mobility aid such as a crutch or a walker you should expect to be able to use it during the test.
If you require both a mobility aid and supplemental oxygen you may receive assistance from the staff performing the test or it may be decided that the test should not be performed. It has been shown that anybody walking with you tends to influence how quickly or how slowly you walk and for this reason any assistance with performing this test is avoided whenever possible.
There are several additional measurements that can be made as part of the test, but these are optional and not required:
- you may have your blood pressure taken before and after the six-minute walk test;
- you may have an oximeter attached to your finger or an earlobe during the walk in order to monitor your oxygen saturation level and heart rate;
- you may be asked how short of breath you are and how tired you are before and after the six-minute walk.
Before the start of the test you may be asked to sit quietly in a chair near one end of the walking course for up to ten minutes in order to be sure you are well-rested. At the start of the test you will be asked to stand next to one of the markers at one end of the walking course. The staff person performing your test will tell you when to start walking.
During the test you should walk as rapidly as you feel you are able to without running or jogging. Your goal is to walk as far as you can. You should not talk during the test. If you get too tired or too short of breath you can stop and recover but the clock does not stop when you do and you should start walking again as soon as you feel you are able to.
Every minute during the test the staff person performing your test will tell you how much time you have left. This person will be keeping track of how far you have walked. Near the end of the walking period you should be given a 15-second warning and then told to stop when the 6 minute walking period is over.
What is a normal measurement?
The distance you were able to walk in 6 minutes is compared to normal values for someone that is your height, weight, age and gender. These normal values will come from one of several different population studies and most frequently this comparison will be the percent of the predicted value. Normal ranges for this test have not been firmly established but it is likely that a walking distance between 75% and 85% of predicted or greater will be considered normal.
A low 6-minute walk distance is not specific to any one condition and cannot be used to diagnose a condition. This test is most useful in assessing an individual's overall health status and motivation level. Changes in an individual's 6-minute walk distance over time can be used to monitor the outcomes of drug treatments, exercise rehabilitation, surgery and other therapies.
What is typical with ILD?
Because an interstitial lung disease can reduce the ability of your lungs to get oxygen into your bloodstream it can limit your exercise capacity. Although there is a general correlation between the severity of ILD and the distance an individual is able to walk, this distance can be affected by other health and mobility problems that are unrelated to ILD.
What affects test quality?
Distractions and obstacles, particularly other pedestrians, can reduce the 6-minute walk distance.