Introduction
Methods
Participants
Study protocol
Variable | Mean ± SD | Min–Max |
---|---|---|
Age [years] | 45.4 ± 9.2 | 35–59 |
Training history [years] | 5 ± 2 | 3–8 |
Body mass index [kg/m2] | 22.0 ± 1.6 | 20.4–22.2 |
Body fat [%] | 10.5 ± 4.8 | 4.7–18.3 |
Weekly covered distance [km] | 83 ± 32 | 30–115 |
VO2max [ml O2/kg/min] | 57.0 ± 4.0 | 53.0–65.0 |
Individual anaerobic threshold [ml O2/kg/min] | 48.3 ± 3.9 | 44.0–56.0 |
LT [%VO2max] | 84.3 ± 3.2 | 80.0–90.0 |
Velocity at LT [km/h] | 13.6 ± 1.0 | 12.0–14.0 |
Workload at LT [W/kg] | 3.6 ± 0.3 | 3.2–4.01 |
Maximal workload [W/kg] | 4.7 ± 0.4 | 4.2–5.3 |
VE max [l/min] | 155 ± 30 | 121–194 |
Peak heart rate [bpm] | 183 ± 12 | 168–201 |
Peak serum lactate [mmol/l] | 9.3 ± 2.7 | 7.4–15.0 |
Biochemical analyses
Statistics
Results
Ultra-marathon performance (see Table 2)
0–12 h running | 13–24 h running | 25–36 h running | 37–48 h running | |||||
---|---|---|---|---|---|---|---|---|
Total distance covered [km] | Actual running speed [km/h] | Total distance covered [km] | Actual running speed [km/h] | Total distance covered [km] | Actual running speed [km/h] | Total distance covered [km] | Actual running speed [km/h] | |
Mean ± SD | 102.6 ± 8.3 | 8.6 ± 0.7 | 169.3 ± 18.7 | 6.0 ± 0.6*** | 222.9 ± 34.9 | 4.7 ± 1.1***#
| 279.8 ± 48.7 | 6.3 ± 0.9** |
Median | 102.0 | 8.5 | 174.0 | 6.0 | 228.0 | 4.9 | 290.6 | 5.9 |
Min–Max | 88.5–114.0 | 7.4–9.5 | 133.5–192.0 | 5.0–6.8 | 156.0–259.5 | 3.2–5.9 | 182.7–319.7 | 5.2–8.1 |
Blood acid–base balance, electrolytes, and iron status (see Table 3)
Variable | Reference range | Pre-race | 12 h running | 24 h running | 48 h running | 24 h post-race | 48 h post-race | ANOVA results | |
---|---|---|---|---|---|---|---|---|---|
pH | 7.350–7.450 | 7.394 ± 0.011 | 7.428 ± 0.026* | 7.440 ± 0.016** | 7.462 ± 0.023*** | 7.440 ± 0.016*** | ND |
F
4,24
= 13.0
|
p < 10
−3
|
pCO2 [mmHg] | 35–45 | 43 ± 2 | 38 ± 4.5** | 38 ± 2** | 36 ± 2*** | 41 ± 1** | ND |
F
4,24
= 15.3
|
p < 10
−3
|
Ca2+[mmol/l] | 1.13–1.30 | 1.22 ± 0.03 | 1.19 ± 0.07 | 1.18 ± 0.05* | 1.15 ± 0.02*** | 1.17 ± 0.02* | ND |
F
4,24
= 10.2
|
p = 0.005
|
Na+[mmol/l] | 135–145 | 141 ± 2 | 140 ± 2 | 138 ± 3 | 137 ± 3* | 140 ± 4 | 138 ± 1** |
F
5,30
= 3.76
|
p = 0.009
|
K+ [mmol/l] | 3.5–5.1 | 4.6 ± 0.2 | 5.1 ± 0.6 | 5.3 ± 0.8 | 5.3 ± 0.6 | 4.7 ± 0.4 | 4.6 ± 0.4 |
F
5,30
= 3.84
|
p = 0.008
|
Glucose [mmol/l] | 3.9–5.8 | 5.3 ± 0.9 | 4.9 ± 1.2 | 5.9 ± 0.9 | 6.1 ± 0.8 | 5.4 ± 0.6 | 5.0 ± 0.7 | F5,30 = 2.47 |
p = 0.055 |
Lactate [mmol/l] | 0.5–2.4 | 2.4 ± 0.5 | 2.3 ± 0.5 | 2.1 ± 0.5 | 2.0 ± 0.7 | 1.6 ± 0.4*** | ND |
F
4,24
= 3.50
|
p = 0.022
|
Fe [μmol/l] | 10.0–30.8 | 15.0 ± 5.2 | 8.1 ± 5.3 | 14.5 ± 4.8 | 5.9 ± 1.7* | 12.5 ± 8.4 | ND |
F
4,24
= 3.80
|
p = 0.016
|
Ferritin [μg/l] | 22–275 | 49 ± 30 | 64 ± 39* | 81 ± 47** | 136 ± 66** | 125 ± 45*** | ND |
F
4,24
= 22.6
|
p < 10
−3
|
sTfR [mg/l]a | 0.83–1.76 | 1.13 ± 1.02 | 1.11 ± 0.96 | 1.01 ± 0.84* | 0.95 ± 0.79*** | 0.86 ± 0.68*** | ND |
F
4,24
= 34.7
|
p < 10
−3
|
sTfR/log10Ferritin index | 0.72 ± 0.15 | 0.66 ± 0.14*** | 0.56 ± 0.13*** | 0.46 ± 0.11*** | 0.42 ± 0.08** | ND |
F
4.24
= 58.2
|
p < 10
−3
|
Blood morphology (see Table 4)
Variable | Reference range | Pre-race | 12 h running | 24 h running | 48 h running | 24 h post-race | 48 h post-race | ANOVA results | |
---|---|---|---|---|---|---|---|---|---|
Hb [g/dl] | 11.2–15.8 | 13.9 ± 0.9 | 14.2 ± 0.6 | 14.0 ± 0.7 | 14.0 ± 1.0 | 12.2 ± 1.1** | 12.2 ± 1.3** |
F
5,30
= 19.8
|
p < 10
−3
|
RBC [×106/μl] | 4.0–5.8 | 4.7 ± 0.4 | 4.8 ± 0.3 | 4.7 ± 0.3 | 4.5 ± 0.4 | 4.1 ± 0.5** | 4.1 ± 0.5** |
F
5,30
= 22.6
|
p < 10
−3
|
HCT [%] | 35–45 | 41 ± 3 | 41 ± 2 | 40 ± 2 | 38 ± 3** | 36 ± 3** | 36 ± 4** |
F
5,30
= 15.5
|
p < 10
−3
|
PLT [×103/μl] | 130–400 | 238 ± 53 | 283 ± 74* | 276 ± 66** | 261 ± 55 | 219 ± 45 | 213 ± 46 |
F
5,30
= 15.6
|
p < 10
−3
|
MCV [fl] | 82.0–98.0 | 87.7 ± 3.5 | 85.4 ± 3.2** | 84.7 ± 3.0*** | 85.4 ± 2.9** | 88.1 ± 3.7 | 89.3 ± 4.0* |
F
5,30
= 48.5
|
p < 10
−3
|
MCH [pg] | 27.0–30.0 | 29.7 ± 1.3 | 29.8 ± 1.2 | 29.8 ± 1.2 | 29.8 ± 1.2 | 30.0 ± 1.3 | 30.1 ± 1.3* |
F
5,30
= 5.40
|
p = 0.0012
|
MCHC [%] | 34.0–36.0 | 33.9 ± 1.0 | 34.9 ± 0.8** | 35.1 ± 0.9*** | 34.9 ± 0.7* | 34.0 ± 1.0 | 33.8 ± 1.1 |
F
5,30
= 30.2
|
p < 10
−3
|
WBC [×109/l] | 4.0–10.0 | 5.4 ± 0.8 | 14.9 ± 3.5** | 13.5 ± 2.6*** | 12.9 ± 3.0** | 7.1 ± 2.0 | 6.0 ± 1.5 |
F
5,30
= 49.5
|
p < 10
−3
|
Neutrophils [× 109/l] | 1.8–7.7 | 3.2 ± 0.5 | 11.3 ± 3.5** | 9.8 ± 2.2** | 9.9 ± 3.3** | 4.6 ± 2.4 | 3.9 ± 1.8 |
F
5,30
= 38.0
|
p < 10
−3
|
Monocytes [×109/l] | 0–0.8 | 0.5 ± 0.1 | 1.4 ± 0.3*** | 1.5 ± 0.5** | 1.1 ± 0.4** | 0.7 ± 0.2** | 0.6 ± 0.2** |
F
5,30
= 37.5
|
p < 10
−3
|
Lymphocytes [×109/l] | 1.0–4.5 | 1.6 ± 0.5 | 2.0 ± 0.8 | 2.1 ± 0.9 | 1.8 ± 0.6 | 1.6 ± 0.5 | 1.4 ± 0.5 |
F
5,30
= 4.82
|
p = 0.0023
|
Blood biochemistry
Variable | URL | Pre-race | 12 h running | 24 h running | 48 h running | 24 h post-race | 48 h post-race | ANOVA results | |
---|---|---|---|---|---|---|---|---|---|
CK [U/l]a
| 174 | 193 ± 79 | 5056 ± 4651*** | 18010 ± 18711*** | 20605 ± 21595*** | 6277 ± 6027*** | 1582 ± 1349*** |
F
5,30
= 68.3
|
p < 10
−3
|
AST [U/l]a
| 42 | 33 ± 6 | 138 ± 95** | 541 ± 517** | 813 ± 896** | 401 ± 428** | 228 ± 251* |
F
5,30
= 45.4
|
p < 10
−3
|
ALT [U/l]a
| 40 | 30 ± 8 | 48 ± 20** | 124 ± 95** | 226 ± 220** | 172 ± 150** | 140 ± 121** |
F
5,30
= 26.2
|
p < 10
−3
|
LDH [U/l]a
| 180 | 193 ± 38 | 377 ± 136** | 700 ± 498** | 1014 ± 916** | 696 ± 569* | 582 ± 487* |
F
5,30
= 23.6
|
p < 10
−3
|
GGT [U/l]a
| 37 | 24 ± 8 | ND | 22 ± 8 | 21 ± 6* | 20 ± 5** | 21 ± 4 |
F
4,24
= 4.09
|
p = 0.012
|
NTproBNP [pg/ml]a
| 125 | 54 ± 50 | 299 ± 194** | 508 ± 458** | 329 ± 412** | ND | 108 ± 86* |
F
4,24
= 21.7
|
p < 10
−3
|
hs-cTnT [ng/ml]a
| 0.016 | 0.004 ± 0.002 | 0.014 ± 0.012* | 0.008 ± 0.006 | 0.008 ± 0.008 | ND | 0.004 ± 0.002 |
F
4,24
= 7.27
|
p < 10
−3
|
IL-6 [pg/ml]a
| 4.72 | 0.64 ± 0.34 | 35.86 ± 17.35*** | 33.25 ± 16.54*** | 23.20 ± 18.85*** | 7.39 ± 13.32** | 2.19 ± 3.67 |
F
5,30
= 84.7
|
p < 10
−3
|
CRP [mg/l]a
| 5.0 | 0.8 ± 0.8 | 3.4 ± 1.7** | 30.0 ± 8.9*** | 63.5 ± 31.5*** | 45.5 ± 37.8*** | 28.0 ± 31.2** |
F
5,30
= 59.3
|
p < 10
−3
|
Variable | Reference range/URL | Pre-race | 12 h running | 24 h running | 48 h running | 24 h post-race | 48 h post-race | ANOVA results | |
---|---|---|---|---|---|---|---|---|---|
TC [mmol/l] | 3.6–6.4 | 5.3 ± 0.3 | ND | 4.7 ± 0.7* | 4.5 ± 0.5** | ND | 4.4 ± 0.4** |
F
3,18
= 10.6
|
p < 10
−3
|
LDL-C [mmol/l] | 3.5 | 3.3 ± 0.3 | ND | 2.8 ± 0.5** | 2.3 ± 0.5*** | ND | 2.5 ± 0.5** |
F
3,18
= 18.8
|
p < 10
−3
|
HDL-C [mmol/l] | 0.7–1.7 | 1.5 ± 0.3 | ND | 1.7 ± 0.3** | 1.9 ± 0.3** | ND | 1.5 ± 0.2 |
F
3,18
= 24.4
|
p < 10
−3
|
TG [mmol/l] | 0.4–1.8 | 1.1 ± 0.5 | ND | 0.4 ± 0.1* | 0.4 ± 0.2* | ND | 0.9 ± 0.3 |
F
3,18
= 9.61
|
p < 10
−3
|
Fatty acids [mmol/l] | 0.1–0.9 | 0.4 ± 0.1 | 2.3 ± 0.2*** | 1.4 ± 0.4** | 1.09 ± 0.3* | 0.6 ± 0.2 | 0.5 ± 0.2 |
F
5,30
= 54.1
|
p < 10
−3
|
βHB [mmol/l]a
| 0.03–0.30 | 0.10 ± 0.03 | 0.30 ± 0.11** | 0.21 ± 0.05* | 0.18 ± 0.08 | 0.08 ± 0.02 | 0.07 ± 0.02 |
F
5,30
= 21.7
|
p < 10
−3
|
Glycerol [μmol/l]a
| 28–108 | 38 ± 17 | 411 ± 142*** | 224 ± 105** | 194 ± 138** | 69 ± 22** | 59 ± 17 |
F
5,30
= 28.3
|
p < 10
−3
|
TC/HDL-C | 4.0 | 3.7 ± 0.5 | ND | 2.8 ± 0.3*** | 2.4 ± 0.3*** | ND | 3.1 ± 0.6** |
F
3,18
= 39.1
|
p < 10
−3
|
LDL-C/HDL-C | 4.5 | 2.3 ± 0.5 | ND | 1.7 ± 0.3*** | 1.3 ± 0.3*** | ND | 1.8 ± 0.6*** |
F
3,18
= 39.2
|
p < 10
−3
|
TG/HDL-C | 3.5 | 0.8 ± 0.4 | ND | 0.2 ± 0.1* | 0.3 ± 0.1* | ND | 0.7 ± 0.3 |
F
3,18
= 9.44
|
p < 10
−3
|
Atherogenic index of plasma (AIP)b
| −0.169 ± 0.220 | ND | −0.661 ± 0.152*** | −0.663 ± 0.245** | ND | −0.218 ± 0.205 |
F
3,18
= 18.9
|
p < 10
−3
|
Blood antioxidant status (see Table 7)
Variable | Reference range | Pre-race | 12 h running | 24 h running | 48 h running | 24 h post-race | 48 h post-race | ANOVA results | |
---|---|---|---|---|---|---|---|---|---|
SOD [IU/g Hb] | 1102–1601 | 1274 ± 341 | 974 ± 101 | 1021 ± 276 | 881 ± 135 | 943 ± 398 | 941 ± 237 |
F
5,30
= 2.92
|
p = 0.029
|
GPX [U/g Hb] | 27.5–73.6 | 48.3 ± 17.0 | 44.2 ± 11.7 | 47.2 ± 11.7 | 47.8 ± 13.2 | 44.9 ± 11.2 | 48.5 ± 14.1 | F5,30 = 0.24 |
p = 0.94 |
GR [U/g Hb] | 27.1 ± 4.1 | 32.6 ± 6.5 | 40.9 ± 13.4 | 35.0 ± 9.6 | 39.3 ± 8.3 | 35.1 ± 8.7 | F5,30 = 2.22 |
p = 0.078 | |
CAT [k/g Hb] | 225 ± 52 | 213 ± 64 | 232 ± 57 | 194 ± 43 | 191 ± 50 | 184 ± 30 | F5,30 = 1.42 |
p = 0.24 | |
Uric acid [mmol/l] | 3.4–7.0 | 5.9 ± 1.0 | 6.8 ± 2.0 | 6.1 ± 1.8 | 5.1 ± 1.1 | 5.3 ± 1.0 | 4.8 ± 0.7 |
F
5,30
= 4.21
|
p = 0.005
|
GSH [μg/mg Hb] | 3.40 ± 0.75 | 3.80 ± 0.47 | 3.70 ± 0.47 | 3.67 ± 0.48 | 5.80 ± 0.95** | 4.91 ± 1.17 |
F
5,30
= 11.22
|
p < 10
−3
| |
TAS [mmol Trolox/l] | 1.30–1.77 | 1.28 ± 0.05 | 1.61 ± 0.17* | 1.31 ± 0.10 | 1.43 ± 0.18 | 1.28 ± 0.16 | 1.35 ± 0.16 |
F
5,30
= 6.39
|
p < 10
−3
|
TBARS [nmol/ml] | 7.03 ± 0.79 | 7.42 ± 0.88 | 7.63 ± 1.02 | 7.19 ± 1.36 | 5.59 ± 1.56 | 7.01 ± 2.12 | F5,30 = 2.17 |
p = 0.11 |