Bubble formation and endothelial function before and after 3 months of dive training

Area of Science:

• Physiology
• Diving Medicine
• Sports Science

Background:

• Repeated compression-decompression cycles may decrease susceptibility to decompression sickness (DCS).
• The impact of intensive dive training on bubble formation and endothelial function requires further investigation.

Purpose of the Study:

• To assess the effect of a 90-day intensive scuba dive training program on bubble formation and endothelial function in military divers.
• To evaluate changes in skin circulation as an indicator of endothelial function.

Main Methods:

• 22 military divers underwent 90 days of physical training and open-sea diving (mean 67 dives).
• Skin blood flow was measured (rest, post-occlusive hyperemia, local heating).
• Venous bubbles were assessed using pulsed Doppler after hyperbaric exposure.

Main Results:

• No DCS occurred during training.
• No significant changes in weight, BMI, maximal oxygen uptake, or endothelial function were observed.
• Bubble grades significantly decreased immediately post-training (16.4 to 3.6) and increased 3 months later.

Conclusions:

• Repeated scuba dives and physical exercise reduce bubble formation, likely offering protection against DCS.
• The exact mechanism is complex and may involve stress response activation, contributing to diving acclimatization.