Effects of load carriage, load position, and walking speed on energy cost of walking
Daijiro Abe1, Kazumasa Yanagawa, Shigemitsu Niihata
1Faculty of Integrated Cultures and Humanities, University of East Asia, 2-1 Ichinomiya Gakuen-cho, Shimonoseki, Yamaguchi 751-8503, Japan. daijiro@po.cc.toua-u.ac.jp
Purpose:
The purpose of this study was to examine the effects of load, load position, and walking speed on the energy cost of walking per unit distance (Cw: ml/kg/m).
Methods:
Eight young male subjects walked on a treadmill at various speeds with and without load in the hands, on the back, and on the legs. The Cw values were determined from the ratio of 2-min steady-state oxygen consumption (Vo2) above resting value (net Vo2) to the walking speed (v): Cw = net Vo2/v.
Results:
An energy-saving phenomenon was observed when the load was carried on the back at slower speeds. This phenomenon diminished at faster speeds, particularly when walking faster than 90 m/min. It was also observed when the load was carried in the hands at slower speeds.
Conclusions:
These findings partly supported our hypothesis that an energy-saving phenomenon would be observed due to an interaction between rotative torque around the center of body mass and excessive burden on the lower muscles as a function of speed.
Related Concept Videos
01:19Impact Loading
In cases of elastic deformation,...
01:17Problem Solving: Energy in Simple Harmonic Motion
Consider the spring in a shock absorber of a car. The spring attached to the wheel executes simple harmonic motion while the car is moving on a bumpy road. The force on the...
01:14Energy Diagrams - I
Take the example of a skater on a parabolic ramp. The potential energy at different points along the ramp will be proportional to the height of the ramp, which varies quadratically with the horizontal position on the ramp. As the skater moves down the ramp from the highest position,...
01:10Work and Energy for Variable Forces