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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

Self- selected gait speed as function of the distance covered while walking on SP TM. Gait speed was averaged over each meter walked for each subject, and group grand average is plotted (gray dots). The SD (±) of this average is represented by the shaded light gray area on both sides of the curve. The black short overlapping curves highlight gait speed values during the 10 m segments (TMS1, TMS2, TMS3, TMS4) which are analogous to four consecutive tests of the over ground 10MWT. Dashed horizontal lines in each panel represent the mean over-ground gait speed, 1.50 ± 0.13 m/s. A. Data from EXPERIMENT A – self- paced treadmill without the presence of the visual virtual reality scenery. B. Data from EXPERIMENT B – self- paced treadmill with the presence of the visual virtual reality scenery. While post hoc comparisons (Bonferroni corrected) yielded no significant difference between TMS3 and TMS4 and GS, mean values of TMS3 and TMS4 showed tendency to be as compared to GS (uncorrected paired t-test; p = 0.058, p = 0.038, respectively). TM- treadmill; VR- virtual reality.
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Fig3: Self- selected gait speed as function of the distance covered while walking on SP TM. Gait speed was averaged over each meter walked for each subject, and group grand average is plotted (gray dots). The SD (±) of this average is represented by the shaded light gray area on both sides of the curve. The black short overlapping curves highlight gait speed values during the 10 m segments (TMS1, TMS2, TMS3, TMS4) which are analogous to four consecutive tests of the over ground 10MWT. Dashed horizontal lines in each panel represent the mean over-ground gait speed, 1.50 ± 0.13 m/s. A. Data from EXPERIMENT A – self- paced treadmill without the presence of the visual virtual reality scenery. B. Data from EXPERIMENT B – self- paced treadmill with the presence of the visual virtual reality scenery. While post hoc comparisons (Bonferroni corrected) yielded no significant difference between TMS3 and TMS4 and GS, mean values of TMS3 and TMS4 showed tendency to be as compared to GS (uncorrected paired t-test; p = 0.058, p = 0.038, respectively). TM- treadmill; VR- virtual reality.

Mentions: Figure 3A depicts, meter by meter, the development of gait speed during SP TM walking, in EXPERIMENT A (panel A). Each data point is the averaged belt speed for one meter of distance passed calculated from the TM tachometer data (light gray data points). The gait speed values during the four designated gait segments are marked by black markers.Figure 3


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)

Self- selected gait speed as function of the distance covered while walking on SP TM. Gait speed was averaged over each meter walked for each subject, and group grand average is plotted (gray dots). The SD (±) of this average is represented by the shaded light gray area on both sides of the curve. The black short overlapping curves highlight gait speed values during the 10 m segments (TMS1, TMS2, TMS3, TMS4) which are analogous to four consecutive tests of the over ground 10MWT. Dashed horizontal lines in each panel represent the mean over-ground gait speed, 1.50 ± 0.13 m/s. A. Data from EXPERIMENT A – self- paced treadmill without the presence of the visual virtual reality scenery. B. Data from EXPERIMENT B – self- paced treadmill with the presence of the visual virtual reality scenery. While post hoc comparisons (Bonferroni corrected) yielded no significant difference between TMS3 and TMS4 and GS, mean values of TMS3 and TMS4 showed tendency to be as compared to GS (uncorrected paired t-test; p = 0.058, p = 0.038, respectively). TM- treadmill; VR- virtual reality.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

Fig3: Self- selected gait speed as function of the distance covered while walking on SP TM. Gait speed was averaged over each meter walked for each subject, and group grand average is plotted (gray dots). The SD (±) of this average is represented by the shaded light gray area on both sides of the curve. The black short overlapping curves highlight gait speed values during the 10 m segments (TMS1, TMS2, TMS3, TMS4) which are analogous to four consecutive tests of the over ground 10MWT. Dashed horizontal lines in each panel represent the mean over-ground gait speed, 1.50 ± 0.13 m/s. A. Data from EXPERIMENT A – self- paced treadmill without the presence of the visual virtual reality scenery. B. Data from EXPERIMENT B – self- paced treadmill with the presence of the visual virtual reality scenery. While post hoc comparisons (Bonferroni corrected) yielded no significant difference between TMS3 and TMS4 and GS, mean values of TMS3 and TMS4 showed tendency to be as compared to GS (uncorrected paired t-test; p = 0.058, p = 0.038, respectively). TM- treadmill; VR- virtual reality.
Mentions: Figure 3A depicts, meter by meter, the development of gait speed during SP TM walking, in EXPERIMENT A (panel A). Each data point is the averaged belt speed for one meter of distance passed calculated from the TM tachometer data (light gray data points). The gait speed values during the four designated gait segments are marked by black markers.Figure 3

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