Table 4.
Resting haematological characteristics of breath-hold divers
| References | Participants | Performance characteristics | Red blood cells | Haemoglobin | Haematocrit | Reticulocytes |
|---|---|---|---|---|---|---|
| Kang et al. (1963) | 20 female habitual BHD (Ama) and 20 female ND | – |
BHD:3.53 ± 0.05 × 106/mm3 ND: 3.63 ± 0.12 × 106/mm3 |
BHD: 12.8 ± 0.2 g/100 ml* ND: 11.9 ± 0.3 g/100 ml |
BHD: 35.1 ± 0.6% ND: 34.6 ± 0.7% |
– |
| Ferretti et al. (1991) | 1 male (age: 57 years) and 2 female EBHD (mean age: 29 years) |
PB Depth No limits category: Male 101 m, and female 70 m and 80 m |
– |
Male: 148 g/L Female: 143 g/L and 137 g/L |
– | – |
| Qvist et al. (1993) | 5 female Korean Ama (age: 38–52 years) | Perform repeated dives to depths of 3–7 m for up to 4 h/day, spending 25–30% of this time underwater and completing > 100 dives during a single workday | – | 12.8 ± 0.3 g/dl | 38.5 ± 0.6% | – |
| Baković et al. (2003) | 10 male trained BHD (age: 28.6 ± 1.7 years) and 10 male untrained individuals (age: 27.8 ± 2.4 years) | Four were national team members | – | – |
BHD: 41.3 ± 0.01% Untrained: 43.8 ± 0.01% |
– |
| Richardson et al. (2005) | 29 male and 4 female EBHD (age: 30.3 ± 10.6 years), 23 elite male skiers (age: 20.2 ± 3 years), 23 male and 9 female untrained individuals (age: 30 ± 6.3 years) |
Training background: 5.5 ± 4 h per week |
– |
EBHD: 150.1 g/L Skiers: 145.5 g/L Untrained: 146.9 g/L |
– | – |
| Bakovic et al. (2005) | 18 trained male BHD and 18 male ND | Years practicing apnoea: 9.5 years (4–26 years) | – |
BHD: 147.7 (125–177 g/L) ND: 147.9 (131–172 g/L) |
BHD: 43% (36–53%) ND: 43% (39–49%) |
– |
| Stewart et al. (2005) | 10 trained BHD (age: 36 ± 11.3 years) and 10 ND (age: 32 ± 9.5 years) | Years practicing apnoea: 17 years | – |
BHD: 14.4 ± 1.6 g/dl ND: 14.2 ± 0.9 g/dl |
BHD: 44.3 ± 5.6% ND: 40.6 ± 4.4% |
– |
| Prommer et al. (2007) | 7 male (age: 35 ± 9 years) and 3 female trained BHD (age: 32 ± 6 years), 7 male Scuba divers (age: 38 ± 11 years), 10 male untrained ND (age: 31 ± 10 years) and 9 non-diving triathletes (age: 31 ± 8 years) |
Training background: 2–3 h, 3 times per week or more over at least the 3 years |
– |
BHD male: 152 ± 5 g/L BHD female: 141 ± 9 g/L Scuba divers: 154 ± 9 g/L Untrained ND: 151 ± 8 g/L Triathletes: 152 ± 10 g/L |
– | – |
| Schagatay et al. (2007) | 7 male BHD (age mean: 27 years [22–35 years]) | – | – | 14.18 ± 0.48 g/dl | 43.5 ± 1.3% | – |
| Kjeld et al. (2009) | 8 male and 1 female trained competitive BHD, 5 male and 1 ND | Current or former national record holders | – | 142 g/L | – | – |
| Richardson et al. (2009) | 10 male BHD |
Training background: < 2 h per week |
– | 134.1 ± 0.8 g/L | 40.9 ± 2% | – |
| Sureda et al. (2015) | 7 male professional spearfishing BHD (age: 30 ± 2.1 years) |
Years practicing apnoea: 5—20 years Training background: 3–4 h diving 5 times per week |
4.93 ± 0.07 × 1012/L | 14.7 ± 0.1 g/dl | 42.8 ± 0.4% | – |
| Oh et al. (2017) | 715 female Haenyeo habitual BHD and 715 matched ND | – | – |
BHD: 13.0 ± 1.2 g/dl ND: 13.0 ± 1.1 g/dl |
– | – |
| Fernandez et al. (2017) | 56 male BHD (age: 36.6 ± 8.5 years [22–57 years]) |
Years practicing apnoea: 2.09 ± 0.7 years |
– |
15.6 ± 1.1 g/dl (14.1—17.7 g/dl) |
– | – |
| Kjeld et al. (2018) | 8 male BHD (age: 42 ± 8 years) and 8 male judo athletes (age: 36 ± 11years) |
PB STA: 403 ± 62 s PB DYN: 163 ± 36 m PB DNF: 133 ± 37 m |
– |
BHD: 15.2 ± 0.8 g/dl ND: 15.3 ± 0.8 g/dl |
– | – |
| Puspitaningrum et al. (2019) | 21 male habitual BHD (Bajau) (age: 15–62 years) | – | – |
15.62 g/dl (12.9–16.9 g/dl) |
– | – |
| Elia et al. (2019b) | 11 male EBHD and 10 male matched control ND |
Years practicing apnoea: 7 ± 2 years Training background: 8 ± 2 h per week PB STA: 414 ± 101 s PB DYN: 202 ± 46 m PB DNF: 145 ± 50 m |
EBHD: 5.43 ± 0.49 •1012/L* (4.80–6.3 × 1012/L) ND: 4.93 ± 0.24 × 1012/L (4.64–5.34 × 1012/L) |
EBHD: 153 ± 6 g/L* (144–161 g/L) ND: 148 ± 3 g/L (145–152 g/L) |
EBHD: 46 ± 4% (42–52%) ND: 45 ± 2% (43–49%) |
EBHD: 1.47 ± 0.29%* (1.1–2%) ND: 1.13 ± 0.30% (0.7–1.6%) |
| Marlinge et al. (2019) | 12 male experienced BHD (age: 37 ± 8 years), 12 male experienced Scuba divers (age: 51 ± 10 years) and 8 male ND (age: 48 ± 4 years) | – | – |
BHD: 15 ± 0.3 g/dl Scuba: 15.2 ± 1.5 g/dl Control: 15.3 ± 0.9 g/dl |
BHD: 45 ± 0.9% Scuba: 44.9 ± 1.2% Control: 45.5 ± 1.8% |
– |
| Fernandez et al. (2019) | 29 male BHD (age: 36 ± 5 years) | Years practicing apnoea: mean of 2 years | – |
15.9 ± 1.2 g/dl 15.4 ± 1.2 g/dl 15.5 ± 0.8 g/dl |
– | – |
| Elia et al. (2021b) | 8 male EBHD and 10 male ND |
Years practicing apnoea: 6 ± 2 years Training background: 9 ± 1 h per week PB STA: 373 ± 35 s PB DYN: 133 ± 42 m |
– |
EBHD: 148 ± 6 g/L ND: 149 ± 4 g/L |
EBHD: 45 ± 2% ND: 45 ± 2% |
– |
BHD breath-hold divers, DNF dynamic apnoea no fins, DYN dynamic apnoea with fins, EBHD elite breath-hold divers, ND non-divers, PB personal best, STA static apnoea
*denotes significance (p<0.05) between groups