Friction Blisters and Sock Fiber Composition, a Single Blind Study (Part 2)

Also published in the Journal of the American Podiatric Medical Association, Volume 83.

Twenty-seven runners (eighteen males and nine females) completed 20 runs of 45 minutes each to compare two generically-constructed socks. One sock was constructed with acrylic fibers and the other with cotton. These non-padded socks were constructed without the dense padding found in the clinically-tested padded socks design. Average run duration was between 6 and 7 miles, an average of 6 days per week. In the study population the results were as follows:

• No significant difference in blister frequency was noted in the generic acrylic cushioned construction as compared with the generic cotton cushioned construction.
• No significant difference in size or severity of blisters was noted in the generic acrylic construction as compared with the generic cotton construction.

Conclusion: Part 1 of this research (Herring and Richie, 1990) demonstrated that there was significant blister reduction in the clinically-tested padded socks construction with acrylic fiber (versus the padded socks with cotton fiber). This might have been interpreted simply as the fact that acrylic is a more effective fiber than cotton in reducing blisters. In order to test this hypothesis, Herring and Richie conducted part 2. The result of this part 2 test was that ordinary socks with a generic cushion construction showed no significant difference in blistering between the acrylic and the cotton constructions. Therefore, the conclusion from the results of the combined studies is that the reduction in blister size and frequency was attributable to a combination of the acrylic yarn construction, together with the clinically-tested padded socks design.