Submitted on April 13, 2007
Accepted on September 5, 2007
Speed training with body weight unloading improves walking energy cost and maximal speed in 75-85 year old healthy women
Elju Eldho Thomas1, Giuseppe De Vito1, and Andrea Macaluso1*
1 Strathclyde Institute of Pharmacy and Biomedical Sciences (SIPBS), University of Strathclyde, Glasgow, Scotland, United Kingdom
* To whom correspondence should be addressed. E-mail: andrea.macaluso{at}strath.ac.uk.
This randomised controlled study was designed to prove the hypothesis that a novel approach to high-speed interval-training, based on walking on a treadmill with the use of body weight unloading (BWU), would have improved energy cost and speed of overground walking in healthy older women. Participants were randomly assigned to either the exercise group (n=11, 79.6±3.7 years, mean ± S.D.) or the non-intervention control group (n=11, 77.6±2.3 years). During the first 6 weeks, the exercise group performed walking interval-training on the treadmill with 40% BWU at the maximal walking speed corresponding to an intensity close to heart rate at ventilatory threshold (Tvent walking speed). Each session consisted of 4 sets of 5-min walking (three 1-min periods at Tvent walking speed, with two 1-min intervals at comfortable walking speed in between each period at Tvent walking speed) with 1-min interval between each set. Speed was increased session by session until the end of week 6. BWU was then progressively reduced to 10% during the last 6 weeks of intervention. Following 12 weeks, the walking energy cost per unit of distance at all self-selected overground walking speeds (slow, comfortable and fast) was significantly reduced in the range from 18% to 21%. The exercise group showed a 13% increase in maximal walking speed and a 67% increase in mechanical power output at Tvent following the training program. The novel "overspeed" training approach has been demonstrated to be effective in improving energy cost and speed of overground walking in healthy older women.
