Sex Differences in Incline-Walking among Humans

Area of Science:

• Biomechanics
• Human Physiology
• Exercise Science

Background:

• Individuals typically adopt walking speeds that minimize energy consumption.
• Previous studies indicate sex-based differences in preferred walking speeds, with women often choosing slower paces during high-intensity activities.

Purpose of the Study:

• To investigate sex-based differences in walking speed selection on an inclined surface, a high-rate activity.
• To analyze the relationship between preferred walking speed, energy cost, and core body temperature in men and women.

Main Methods:

• Participants (9 men, 5 women) walked at various speeds on level and inclined treadmills.
• Metabolic rate, kinematics, and core temperature were monitored during walking trials.
• Cost of transport (CoT) was calculated, and the difference between preferred and optimal speeds was determined.

Main Results:

• Participants generally selected slightly slower walking speeds on level surfaces with minimal impact on energy cost.
• Women walked at significantly slower speeds on inclines and exhibited larger differences between preferred and optimal speeds compared to men.
• A significant correlation between activity rate and core temperature was observed in women, but not in men.

Conclusions:

• Women employ behavioral strategies to minimize core body temperature fluctuations during high-rate walking activities like incline walking.
• Sex-based differences in preferred walking speeds are influenced by the metabolic cost and thermal regulation demands of the activity.