One question that has come across my clinical desk recently, that I was not able to answer…what is the norm for the 6 Minute Walk Test for a 15 year old girl?
Last month, as I work on updating my Fit4Work presentations, I was able to delve into the literature on this topic. At APPTAC, Carlo Vialu shared some information on the 2 Minute Walk test, but I just wasn't able to digest until I read a little deeper.
The 2 Minute Walk test has been developed as a part of the NIH toolbox. In a recent study, Bohannan et al (2014) reported that gait speed is likely to be stable whether you walk 2 minutes or whether you walk 6 minutes. Which is probably why the 2 Minute Walk test was selected for the NIH toolbox over the 6 Minute Walk Test.
In a recent systematic review, Cacau et al (2017) discuss the reference values for the 6 Minute Walk Test, citing large discrepancies between countries for reference values. The only US study for reference values includes 100 children from age 7-11. I was notable to locate any norms for teens...ok so there is the answer to my question...
Clinically, I have used the 6 Minute Walk test since I started using Fit4Work concepts in evaluation. In the cases where there was not cardiovascular fitness data, I felt that this would be a good measure of how much a student could walk. Actually, I want to know if my kids have the stamina to be on their feet walking for 1-2 hours...but 6 Minutes is a quick and easy test and it has proven to work great as an outcomes measure. I have collaborated with PE teachers on IEP goals speaking to the 6 Minute Walk Test and we have repeated it quarterly. It has been robust enough to show an increase in student's walking speed.
What to do moving forward? I am going to start using the 2 Minute Walk Test when I am interested in evaluating walking tolerance. If you choose to compare your student to the NIH norms, be sure to understand that you are comparing your student to a person without a disability, which many consider to be an unfair comparison given that there will be differences in body structure and function. However, these large scale population norms are quite robust and should be used with confidence.