Spearfishing Freediving Physiology for Spearfishing 2

Question 1

What is 'static apnea' and how does it help spearfishers improve performance?

Accepted Answer

Breath-hold without movement to train CO2 tolerance and extend maximum breathhold duration

Answer

Static apnea trains the diver's tolerance to CO2 buildup and psychological discomfort, directly translating to longer, more relaxed breathhold times underwater.

Question 2

What physical phenomenon causes a diver's wetsuit to provide less buoyancy at depth compared to the surface?

Accepted Answer

Neoprene cells compress under pressure, reducing the air trapped in the material and decreasing buoyancy

Answer

Neoprene is composed of closed-cell foam; as pressure increases with depth, the cells compress, reducing suit thickness and buoyant lift, causing the diver to become more negatively buoyant.

Question 3

What is the role of the spleen in elite freedivers' breath-hold performance?

Accepted Answer

The spleen contracts under diving stimulus, releasing stored red blood cells and increasing blood oxygen-carrying capacity

Answer

The spleen acts as a blood oxygen reservoir; during breath-hold, it contracts and injects RBC-rich blood into circulation, boosting oxygen capacity — a key adaptation in trained freedivers.

Question 4

What physical symptom should a spearfisher take as a warning sign to immediately surface during a dive?

Accepted Answer

Diaphragm contractions becoming very strong and rhythmic (strong urge to breathe contractions)

Answer

Strong, involuntary diaphragmatic contractions indicate dangerously low oxygen; these are the body's emergency signals to breathe and must be respected immediately.

Question 5

Why should spearfishers avoid consuming large meals before diving?

Accepted Answer

Digestion increases metabolic oxygen demand, reducing available oxygen for the dive and increasing blackout risk

Answer

Active digestion diverts blood oxygen to the digestive system and raises metabolic rate, reducing the oxygen available for the dive and increasing susceptibility to shallow water blackout.

Spearfishing Practice Test

Spearfishing Practice Test

Spearfishing Freediving Physiology for Spearfishing 2