Predicting marching capacity while carrying extremely heavy loads

Area of Science:

• Military Science
• Human Physiology
• Biomechanics

Background:

• Endurance time for soldiers carrying heavy loads is critical for mission success.
• Predicting performance under load requires understanding the relationship between load and physiological capacity.

Purpose of the Study:

• To determine the optimal method for predicting endurance time in combat soldiers marching with heavy loads.
• To compare the predictive power of different load metrics (absolute load, % body mass, % lean body mass, % MLCC) on endurance time.

Main Methods:

• Twenty-three male combat soldiers underwent maximal load carry capacity (MLCC) testing.
• Soldiers marched at 3 km/h on a 5% gradient, carrying 70%, 80%, and 90% of their determined MLCC.
• Endurance time was recorded for each load condition.

Main Results:

• Load expressed as a percentage of maximal load carry capacity (% MLCC) was the strongest predictor of endurance time (R² = 0.45).
• Load relative to body mass (R² = 0.30), lean body mass (R² = 0.24), and absolute load (R² = 0.23) were less effective predictors.
• Individual MLCC averaged 102.6 kg ± 11.6 kg.

Conclusions:

• Assessing individual maximal load carry capacity (MLCC) is recommended for accurately predicting combat soldier endurance.
• Using % MLCC provides a superior prediction of marching endurance compared to other load metrics.
• This finding has implications for load management and soldier performance optimization.