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Self-selected gait speed--over ground versus self-paced treadmill walking, a solution for a paradox.

Plotnik M, Azrad T, Bondi M, Bahat Y, Gimmon Y, Zeilig G, Inzelberg R, Siev-Ner I - J Neuroeng Rehabil (2015)

Bottom Line: We compared over ground walking vs.Gait speed was compared across conditions for four 10 m long segments (7.5 - 17.5, 30.5 - 40.5, 55.5 - 65.5 and 78.5-88.5 m).We propose that the gait research community joins forces to standardize the use of SP TMs, e.g., by unifying protocols or gathering normative data.

View Article: PubMed Central - PubMed

Affiliation: Center of Advanced Technologies in Rehabilitation, Sheba Medical Center, Tel Hashomer, Israel. meir.plotnik@sheba.health.gov.il.

ABSTRACT

Background: The study of gait at self-selected speed is important. Traditional gait laboratories being relatively limited in space provide insufficient path length, while treadmill (TM) walking compromises natural gait by imposing speed variables. Self-paced (SP) walking can be realized on TM using feedback-controlled belt speed. We compared over ground walking vs. SP TM in two self-selected gait speed experiments: without visual flow, and while subjects were immersed in a virtual reality (VR) environment inducing natural visual flow.

Methods: Young healthy subjects walked 96 meters at self-selected comfortable speed, first over ground and then on the SP TM without (n=15), and with VR visual flow (n=11). Gait speed was compared across conditions for four 10 m long segments (7.5 - 17.5, 30.5 - 40.5, 55.5 - 65.5 and 78.5-88.5 m).

Results: During over ground walking mean (± SD) gait speed was equal for both experimental groups (1.50 ± 0.13 m/s). Without visual flow, gait speed over SP TM was smaller in the first and second epochs as compared to over ground (first: 1.15 ±0.18 vs. second: 1.53 ± 0.13 m/s; p<0.05), and was comparable in the third and fourth (1.45 ± 0.19 vs. 1.49 ± 0.15 m/s; p>0.3). With visual flow, gait speed became comparable to that of over ground performance already in the first epoch (1.43 ± 0.22 m/s; p>0.17). Curve fitting analyses estimated that steady state velocity in SP TM walking is reached after shorter distanced passed with visual flow (24.6 ± 14.7 m) versus without (36.5 ± 18.7 m, not statistically significant; p=0.097). Steady state velocity was estimated to be higher in the presence of visual flow (1.61 ± 0.17 m/s) versus its absence (1.42 ± 1.19 m/s; p<0.05).

Conclusions: The SP TM walking is a reliable method for recording typical self-selected gait speed, provided that sufficient distance is first passed for reaching steady state. Seemingly, in the presence of VR visual flow, steady state of gait speed is reached faster. We propose that the gait research community joins forces to standardize the use of SP TMs, e.g., by unifying protocols or gathering normative data.

No MeSH data available.


Related in: MedlinePlus

Differential effect of visual virtual scenery on self- selected gait speed. For each subject, gait speed values during TM walking were normalized with respect to the GS value. Box plots for normalized TMS1 – TMS4 are plotted for EXPERIMENT A (gray boxes) and for EXPERIMENT B (light green boxes). The horizontal dashed line represents the GS (i.e., = 1).
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Fig4: Differential effect of visual virtual scenery on self- selected gait speed. For each subject, gait speed values during TM walking were normalized with respect to the GS value. Box plots for normalized TMS1 – TMS4 are plotted for EXPERIMENT A (gray boxes) and for EXPERIMENT B (light green boxes). The horizontal dashed line represents the GS (i.e., = 1).

Mentions: Multiple non parametric statistical comparisons (Mann Whitney U-test) were used to detect a differential effect (Figure 4). It can be seen that generally the relative values of TMS in each of the gait segments are greater in EXPERIMENT B as compared to EXPERIMENT A (p < 0.04; for TMS1, TMS2 and TMS4; p = 0.06 for TMS3; Bonferroni corrected, k = 4).Figure 4


Self-selected gait speed--over ground versus self-paced treadmill walking, a solution for a paradox.

Plotnik M, Azrad T, Bondi M, Bahat Y, Gimmon Y, Zeilig G, Inzelberg R, Siev-Ner I - J Neuroeng Rehabil (2015)

Differential effect of visual virtual scenery on self- selected gait speed. For each subject, gait speed values during TM walking were normalized with respect to the GS value. Box plots for normalized TMS1 – TMS4 are plotted for EXPERIMENT A (gray boxes) and for EXPERIMENT B (light green boxes). The horizontal dashed line represents the GS (i.e., = 1).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4374285&req=5

Fig4: Differential effect of visual virtual scenery on self- selected gait speed. For each subject, gait speed values during TM walking were normalized with respect to the GS value. Box plots for normalized TMS1 – TMS4 are plotted for EXPERIMENT A (gray boxes) and for EXPERIMENT B (light green boxes). The horizontal dashed line represents the GS (i.e., = 1).
Mentions: Multiple non parametric statistical comparisons (Mann Whitney U-test) were used to detect a differential effect (Figure 4). It can be seen that generally the relative values of TMS in each of the gait segments are greater in EXPERIMENT B as compared to EXPERIMENT A (p < 0.04; for TMS1, TMS2 and TMS4; p = 0.06 for TMS3; Bonferroni corrected, k = 4).Figure 4

Bottom Line: We compared over ground walking vs.Gait speed was compared across conditions for four 10 m long segments (7.5 - 17.5, 30.5 - 40.5, 55.5 - 65.5 and 78.5-88.5 m).We propose that the gait research community joins forces to standardize the use of SP TMs, e.g., by unifying protocols or gathering normative data.

View Article: PubMed Central - PubMed

Affiliation: Center of Advanced Technologies in Rehabilitation, Sheba Medical Center, Tel Hashomer, Israel. meir.plotnik@sheba.health.gov.il.

ABSTRACT

Background: The study of gait at self-selected speed is important. Traditional gait laboratories being relatively limited in space provide insufficient path length, while treadmill (TM) walking compromises natural gait by imposing speed variables. Self-paced (SP) walking can be realized on TM using feedback-controlled belt speed. We compared over ground walking vs. SP TM in two self-selected gait speed experiments: without visual flow, and while subjects were immersed in a virtual reality (VR) environment inducing natural visual flow.

Methods: Young healthy subjects walked 96 meters at self-selected comfortable speed, first over ground and then on the SP TM without (n=15), and with VR visual flow (n=11). Gait speed was compared across conditions for four 10 m long segments (7.5 - 17.5, 30.5 - 40.5, 55.5 - 65.5 and 78.5-88.5 m).

Results: During over ground walking mean (± SD) gait speed was equal for both experimental groups (1.50 ± 0.13 m/s). Without visual flow, gait speed over SP TM was smaller in the first and second epochs as compared to over ground (first: 1.15 ±0.18 vs. second: 1.53 ± 0.13 m/s; p<0.05), and was comparable in the third and fourth (1.45 ± 0.19 vs. 1.49 ± 0.15 m/s; p>0.3). With visual flow, gait speed became comparable to that of over ground performance already in the first epoch (1.43 ± 0.22 m/s; p>0.17). Curve fitting analyses estimated that steady state velocity in SP TM walking is reached after shorter distanced passed with visual flow (24.6 ± 14.7 m) versus without (36.5 ± 18.7 m, not statistically significant; p=0.097). Steady state velocity was estimated to be higher in the presence of visual flow (1.61 ± 0.17 m/s) versus its absence (1.42 ± 1.19 m/s; p<0.05).

Conclusions: The SP TM walking is a reliable method for recording typical self-selected gait speed, provided that sufficient distance is first passed for reaching steady state. Seemingly, in the presence of VR visual flow, steady state of gait speed is reached faster. We propose that the gait research community joins forces to standardize the use of SP TMs, e.g., by unifying protocols or gathering normative data.

No MeSH data available.


Related in: MedlinePlus