Physiological responses during static apnoea efforts in elite and novice breath-hold divers before and after two weeks of dry apnoea training

This study examined the effect of breath-hold (BH) training on apnoeic performance in novice BH divers (NBH:n = 10) and compared them with data from elite BH divers (EBH:n = 11). Both groups performed 5-maximal BHs (PRE). The NBH group repeated this protocol after two weeks of BH training (POST). The NBH group during BH efforts significantly increased red blood cell concentration (4.56 +/- 0.16Mio/mu l) by 5.06%, hemoglobin oxygen saturation steady state duration (110.32 +/- 29.84 s) by 15.48%, and breath-hold time (BHT:144.19 +/- 47.35 s) by 33.77%, primarily due to a 59.70% increase in struggle phase (71.85 +/- 30.89 s), in POST. EBH group exhibited longer BHT (283.95 +/- 36.93 s) and struggle-phase (150.10 +/- 34.69 s) than NBH (POST). Elite divers recorded a higher peak MAP (153.18 +/- 12.28 mmHg) compared to novices (PRE:123.70 +/- 15.65 mmHg, POST:128.30 +/- 19.16 mmHg), suggesting that a higher peak MAP is associated with a better BHT. The concurrent abrupt in-crease of diaphragmatic activity and MAP, seen only in the EBH group, suggests a potential interaction. Addi-tionally, apnoea training increases red blood cells concentration in repeated apnoea efforts and increases BH stamina.