Can GPS be used to detect deleterious progression in training volume among runners? (2013)

Abstract

There is a need to ascertain if an association exists between excessive progression in weekly volume and development of running-related injuries (RRI). The purpose of this study was to investigate if GPS can be used to detect deleterious progression in weekly training volume among 60 novice runners included in a 10-week prospective study. All participants used GPS to quantify training volume while running. In case of injury, participants attended a clinical examination. The 13 runners who sustained injuries during follow-up had a significantly higher weekly progression in total training volume in the week before the injury origin (86% [95% confidence interval: 12.9-159.9], p = 0.026) compared with other weeks. Although not significant, participants with injuries had an increase in weekly training volume of 31.6% compared with a 22.1% increase among the healthy participants. The error of the GPS measurements in open landscape, forest, and urban area of volume was ≤6.2%. To conclude, no clinically relevant measurement errors of the GPS devices were found for training volume. Based on this, GPS has a potential to detect errors in training volume, which may be associated with development of RRI. Based on the results from the current study, increases in weekly training progression may become deleterious at a weekly increase above 30%, which is more than the 10% rule currently used as a guideline for correct progression in weekly volume by runners and coaches. Still, no clear evidence for safe progression of weekly volume exists. But it seems likely that some individuals may tolerate weekly progressions around 20-25%, at least for a short period of time.

My comments

This study didn’t find statistical significance in volume as related to injury but the trend was towards more injuries as people increased their training volume above 30% per week. The traditional wisdom is to tell runners not to increase volume more than 10% per week. However, the traditional wisdom has no research behind it whatsoever. So I’ll take a non-significant trend over an absence of data more often than not.

In addition, they referenced the Bruist et al study, which found no difference in injury rates between runners who increased their training volume 10% per week vs 24% per week. So taken together it seems, at least for novice runners, the 10% increase in volume is is too conservative and likely holds back peoples’ fitness levels; greater than 30% is too aggressive, so 20-25% seems reasonable to me.