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Updated: Jul 15, 2026

Dual Test Gas Pulmonary Diffusing Capacity Measurement During Exercise in Humans Using the Single-Breath Method
Published on: February 2, 2024
No gender-specific differences in mechanical efficiency during arm or leg exercise relative to ventilatory threshold
N Yasuda1, S E Gaskill, B C Ruby
1Department of Health and Human Performance, The University of Montana, Missoula, MT, USA.
Abstract:
The purpose of this study was to determine economy and mechanical efficiency in men and women during both arm cranking (AC) and leg cycling (LC) at 70%, 85%, 100%, and 115% of mode-specific ventilatory threshold (T(vent)). Recreationally active men (n=9) and women (n=9) with similar values for %VO2peak at T(vent) served as subjects. All subjects performed 5 min of exercise at each intensity of 70%, 85%, 100%, and 115% of T(vent) for both AC and LC. Economy was expressed as W/L/min. Gross efficiency (GE) was determined as the ratio of work accomplished to total energy expended (%). Delta efficiency (DE) was determined as the ratio of delta work accomplished to delta energy expended (%). Economy and efficiency during LC were greater than during AC in men and women. During AC or LC exercise, no sex differences were found in either economy (P=0.93 for AC, 0.98 for LC), GE (P=0.88 for AC, 0.75 for LC), or DE (P=0.57 for AC, 0.51 for LC). These findings indicate that men and women show similar economy and efficiency during both AC and LC exercise when subjects have similar %VO2peak at Tvent.
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