Effect of an overground walking training on gait performance in healthy 65-to 80-year-olds

The aim of this study was to examine the effect of an individualized overground walking interval training on gait performance [i.e., speed and energy cost (C-w)] in healthy elderly individuals. Twenty-two older adults were assigned to either a training group (TG; n = 12, 73.4 +/- 3.9 yr) or a non-training control group (CG; n = 10, 70.9 +/- 9.6 yr). TG participated in a 7-week individualized walking interval training at intensities progressing from 50 to 100% of ventilatory threshold ((T) over dot(VE)). Aerobic fitness [maximal oxygen uptake ((V) over dotO(2max)) and (T) over dot(VE)], preferred walking speed (PWS), gross and net C-w (GC(w) and NCw respectively) and relative effort (%(V) over dotO(2max)) at PWS measured before training (PWS1) were assessed prior and following the intervention. All outcomes were measured on a treadmill. Significant improvements in GC(w) (-8%; P = 0.007), NCw (-12%; P = 0.003), relative effort (%(V) over dotO(2max): -12%; P <0.001) and PWS (+12%; P <0.001) were observed in TG but not in CG (P> 0.71). (V) over dotO(2max) and (T) over dot(VE) remained unchanged in both groups (P > 0.57). Changes in GC(w) at PWS1 (difference between GC(w) at PWS1 measured pre and post intervention) were inversely correlated with changes in PWS (difference between pre and post PWS; r= -0.67; P = 0.02). The decreased C-w at PWS1 with no concomitant improvement in aerobic fitness, represents the main contributing factor for the reduction of the relative effort at this speed. This also allows elderly people to increase their PWS post training. Therefore, the present walking training may be an effective way to improve walking performance and delay mobility impairment in older adults. (C) 2010 Elsevier Inc. All rights reserved.