Daily Variation in Step Length of Trained Male Runners

Abstract

The purpose of this study was to quantify daily intra-individual variability in mean step length, a basic descriptor for the running pattern. Following 60 minutes of treadmill accommodation, nine trained male subjects (X age = 34.2 yrs +/- 7.2, X VO2max = 57.0 +/- 4.8 ml.kg-1.min-1) performed daily (Mon-Fri) 6-minute treadmill runs at three submaximal speeds (2.68, 3.13 and 3.58 m.s-1) over a 4-week period. To minimize extraneous influences, subjects refrained from road racing and completed the 20 running sessions (5 d.wk-1.4 weeks for each speed) at the same time of day and in the same footwear. Treadmill velocity was calibrated for each 6-minute running bout and step length was determined during the last 2 minutes of each run. Results indicated that mean step length and coefficient of variation values were 0.984 m and 2.50% at 2.68 m.s-1, 1.124 m and 2.22% at 3.13 m.s-1, and 1.254 m and 2.26% at 3.58 m.s-1. Reliability analyses indicated that the percentage of variation accounted for in step length across all speeds was high and improved very little as test number increased (range = 96% for two days vs 99% for five days). Taken together, these findings suggest that when testing conditions are controlled, within-subject variability in step length measures obtained at multiple submaximal running speeds is small in trained subjects and that criterion step length values can be obtained by averaging duplicate measurements.

Ambulatory running speed estimation using an inertial sensor

“…reported that stride length can vary up to 2.50% at approximately the same speed range used in this study [14]. It is also speculated that this value would increase in untrained runners, such as those that participated in this study.…”

“…The stride-tostride variability of the estimated speed is within the range of natural variation in human stride length and timing during running. Several studies [15,16,14] have investigated these variations in trained athletes running on treadmills. Craib et al…”

Lower Extremity Biomechanics and Self-Reported Foot-Strike Patterns Among Runners in Traditional and Minimalist Shoes

“…[23][24][25] Data collection consisted of five 3-second trials during the final minute of running. 26,27 To reduce measurement bias, participants were blinded to exactly when data were being collected.…”

A Comparison of Negative Joint Work and Vertical Ground Reaction Force Loading Rates in Chi Runners and Rearfoot-Striking Runners

“…During the first 4 minutes of running, the subjects were allowed to accommodate themselves to the treadmill, 14,19,24 and during the final minute of running data were collected in 5 three-second periods. 2,7 To reduce measurement bias, subjects were blinded to the data-collection times.…”