Article

The effects of backpack load on young adults' gait parameters have
received little attention. We previously reported that with a backpack load
within 15% body weight (BW), young adults maintain their gait parameters at the
expense of increased exertion during a 6-minute walk at self-selected normal
walking speed. However, the effect of backpack strap pattern on gait parameters
during faster walking or longer stride length has not been evaluated. OBJECTIVE:
To determine the effect of different backpack strap patterns on gait parameters
during a 12-minute walk test in young adults at self-selected normal and fast
walking speeds. DESIGN: A crossover, self-controlled experimental study with
repeated measures. SETTING: Department of Medical Rehabilitation, University of
Nigeria. PARTICIPANTS: A convenience sample of 24 healthy young adults (21.29 +/-
1.20 years) who voluntarily signed an informed consent form, were able to wear a
backpack on 1 and on both shoulders, were able to walk independently, and passed
the physical activity readiness screening participated in this study. METHODS:
Using a validated method of an observational gait analysis, each participant
carried out a 12-minute walk test at self-determined normal and fast walking
speeds, respectively. The effect of the following test conditions on the selected
gait parameters was evaluated: normal and fast walking without load, and normal
and fast walking with 10% and 20% BW backpack carried each on 1 and both
shoulders. MAIN OUTCOME MEASUREMENT: Stride length, stride time, velocity,
cadence, and base of support were assessed by the equation definitions method of
the velocity field diagram. RESULTS: At self-selected fast walking speed with 10%
BW backpack load, stride time (P = .004) and cadence (P = .006) were
significantly decreased when participants wore a double-strap backpack. At
self-selected normal walking speed with 20% BW backpack load, cadence was
significantly decreased with double-strap backpack carriage (P = .008). Cadence
(P < .001), velocity (P < .001), and stride time (P < .001)were also
significantly decreased at both conditions of single and double-strap backpack
carriage of 20% BW respectively at fast walking speed. CONCLUSION: Backpack strap
patterns do not affect the gait parameters of young adults in a 12-minute bout of
normal walking speed, provided that the load is less than 20% BW. However, a load
up to 10% BW carried on a double strap causes a decrease in stride time and
cadence when these individuals walk fast. LEVEL OF EVIDENCE: Not applicable.
CI - Copyright (c) 2017 American Academy of Physical Medicine and Rehabilitation.
Published by Elsevier Inc. All rights reserved.

Langue : ANGLAIS