Gender differences during treadmill walking with graded loads: biomechanical and physiological comparisons

Area of Science:

• Biomechanics
• Human Physiology
• Exercise Science

Background:

• Understanding gender-based differences in physiological responses to load carriage is crucial for occupational safety and military applications.
• Previous research indicates potential disparities in how men and women manage physical stress during demanding tasks.

Purpose of the Study:

• To compare the biomechanical and physiological responses of healthy men and women during bilateral load carriage while walking.
• To investigate gender-specific differences in oxygen uptake, cardiovascular stress, and load distribution during load carriage.

Main Methods:

• Eleven men and 11 women walked on a treadmill carrying 15-kg and 20-kg loads using a custom device.
• Measurements included oxygen uptake, cardiac output (via CO2 rebreathing), heart rate, and blood pressure.
• Load distribution between hands and body was quantified using strain gauges.

Main Results:

• Women transferred a greater proportion of the load to their bodies by resting it against the chest.
• Oxygen uptake increased more in women, exceeding the ventilatory threshold at 20 kg.
• Cardiovascular stress (maximal heart rate and rate pressure product) was significantly higher in women.

Conclusions:

• Women exhibit greater physiological strain and cardiovascular stress compared to men under identical absolute load carriage conditions.
• These findings suggest women may be more susceptible to fatigue and at a higher risk of cardiovascular complications during load carriage.
• Load carriage strategies differ between genders, with women utilizing more passive body support.