Energy Balance and Energy Availability During a Selection Course for Belgian Paratroopers

Area of Science:

• Sports Science
• Military Nutrition
• Human Physiology

Background:

• Optimal athletic performance and recovery are critically dependent on adequate energy supply.
• Military selection courses impose high physical demands, necessitating careful energy balance monitoring.
• Understanding energy availability is crucial for preventing fatigue and maintaining soldier effectiveness.

Purpose of the Study:

• To quantify energy balance and energy availability in Belgian paratrooper candidates during a selection course.
• To assess the adequacy of prescribed energy intake relative to high physical demands.

Main Methods:

• Energy expenditure was measured using accelerometry and equations for resting metabolic rate.
• Energy intake was standardized to 3,600 Cal/day using French individual combat rations.
• Body composition (fat mass) was assessed using quadripolar impedance.
• Energy availability was calculated as ([energy intake] - [energy expenditure]) / fat-free mass.

Main Results:

• Mean total energy expenditure was 5,262 Cal/day, significantly exceeding the 3,600 Cal/day intake.
• This resulted in a mean negative energy balance of 1,662 Cal/day and low energy availability (9.3 Cal/kg FFM/day).
• A substantial proportion of participants (11/35) experienced a deficit exceeding 2,000 Cal/day.

Conclusions:

• The prescribed energy intake was insufficient to meet the high energy demands of the paratrooper selection course.
• Participants operated under conditions of negative energy balance and low energy availability, compromising performance.
• Nutritional strategies require optimization to ensure adequate energy supply during intense military training.