Effects of timing and magnitude of forward forces at the waist on the metabolic cost of walking

Studies showed that a constant forward traction force applied at the waist can reduce metabolic cost. However, there is limited information about the effects of non-constant forces. Our aim was to investigate the effects of timing and magnitude of different forward force profiles on metabolic cost. We found that conditions with timings that overlap with the acceleration phase of the center-of-mass, long durations and high (but not maximal) force magnitudes produced the highest reductions in metabolic cost.