Maximal fat oxidation in navy divers.

Area of Science:

• Exercise Physiology
• Sports Science
• Diving Medicine

Background:

• Fat oxidation requires more oxygen than carbohydrate utilization, impacting endurance performance.
• Hyperoxia can acutely increase fat oxidation, relevant for diving environments.
• Limited research exists on substrate utilization changes in divers during training.

Purpose of the Study:

• To evaluate changes in maximal fat oxidation (MFO) in navy divers undergoing specific training programs.
• To investigate the effects of diver training on energy substrate utilization.

Main Methods:

• Recruited explosive ordnance disposal (EOD) divers, combat divers, and amphibious rangers (controls).
• Measured MFO using indirect calorimetry via incremental tests before and after 15-16 weeks of training.
• Employed treadmill and bicycle ergometer protocols under normoxic and hyperoxic conditions.

Main Results:

• Combat divers demonstrated a significant increase in MFO (0.14 g/minute).
• No significant changes in MFO were observed in EOD divers or control groups.
• Training protocols varied in duration and environmental conditions (normoxia/hyperoxia).

Conclusions:

• Combat diver training can enhance maximal fat oxidation capacity.
• Potential contributing factors include training stressors like hyperoxia, load, and energy balance.
• Increased fat oxidation may influence oxygen consumption and carbon dioxide production in divers.