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Updated: Jul 29, 2026

Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI
Published on: April 18, 2011
Brief High-Velocity Motor Skill Training Increases Step Frequency and Improves Length/Frequency Coordination in Slow
Nicholas H Evans1, Edelle C Field-Fote2
1Shepherd Center, Crawford Research Institute, Atlanta, GA.
Objective:
To quantify spatiotemporal coordination during overground walking among persons with motor-incomplete spinal cord injury (PwMISCI) by calculating the step length (SL)/step frequency (SF) ratio (ie, the Walk Ratio [WR]) and to examine the effects of motor skill training (MST) on the relationship between changes in these parameters and walking speed (WS).
Design:
Between-day exploratory analysis.
Setting:
Research laboratory in a rehabilitation hospital PARTICIPANTS: PwMISCI (N=26).
Interventions:
3-day high-velocity MST.
Main Outcome Measures:
Overground WS, SL, SF, and WR measured during the 10-Meter Walk Test.
Results:
Among the full sample, MST was associated with increases in WS, SL, SF, and a decrease in the WR. Relative change in WS and SF was higher among slow (ΔWS=↑46%, ΔSF=↑28%) vs fast (ΔWS=↑16%, ΔSF=↑8%) walkers. Change in the WR differed between groups (slow: ΔWR=↓10%; fast: ΔWR=0%). Twenty-six percent of the variability observed in ΔWR among slow walkers could be explained by ΔSF, while ΔSL did not contribute to ΔWR. Among fast walkers, ΔSL accounted for more than twice the observed ΔWR (43%) compared to ΔSF (15%).
Conclusions:
On the whole, WR values among PwMISCI are higher than previous reports in other neurologic populations; however, values among fast walkers were comparable to noninjured adults. Slow walkers demonstrated greater variability in the WR, with higher values associated with slower WS. Following MST, increases in WS coincided with a decrease in the WR among slow walkers, mediated primarily through an effect on SF. This finding may point to a specific mechanism by which MST facilitates improvements in WS among PwMISCI with greater mobility deficits.
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