Table 3. Cardiorespiratory, cerebral and muscle responses to hypoxia at rest and during cycling exercise before and after one month of NO precursor supplementation.
PRE |
POST |
∆PRE/POST |
p∆ |
d∆ |
|||||||||||||||||||||||
Rest |
∆HR (bpm) |
N+C |
6.6 |
± |
6.5 |
4.6 |
± |
2.9 |
-2.6 |
± |
5.9 |
0.225 |
0.321 |
||||||||||||||
PLA |
5.3 |
± |
4.2 |
4.8 |
± |
5.2 |
-0.6 |
± |
6.4 |
||||||||||||||||||
∆VE (l·min-1) |
N+C |
-2.0 |
± |
1.2 |
-1.5 |
± |
1.4 |
0.4 |
± |
1.8 |
0.130 |
0.470 |
|||||||||||||||
PLA |
-1.1 |
± |
1.7 |
-1.6 |
± |
2.1 |
-0.5 |
± |
2.0 |
||||||||||||||||||
∆SpO2 (%) |
N+C |
86.6 |
± |
4.4 |
86.7 |
± |
4.4 |
-0.5 |
± |
4.7 |
0.400 |
0.110 |
|||||||||||||||
PLA |
83.9 |
± |
7.9 |
83.6 |
± |
4.4 |
0.3 |
± |
9.5 |
||||||||||||||||||
∆TSI% |
Cerebral |
N+C |
-4.3 |
± |
7.6 |
-3.7 |
± |
1.9 |
-1.5 |
± |
7.5 |
0.440 |
0.768 |
||||||||||||||
PLA |
-4.4 |
± |
3.2 |
-3.9 |
± |
2.3 |
0.5 |
± |
3.1 |
||||||||||||||||||
Muscle |
N+C |
-0.8 |
± |
2.0 |
0.2 |
± |
4.3 |
0.7 |
± |
4.7 |
0.260 |
0.959 |
|||||||||||||||
PLA |
-0.3 |
± |
1.0 |
-1.4 |
± |
1.7 |
-1.1 |
± |
1.4 |
||||||||||||||||||
Cycling |
∆HR (bpm) |
N+C |
10.9 |
± |
9.9 |
14.3 |
± |
7.6 |
3.4 |
± |
8.9 |
0.280 |
0.240 |
||||||||||||||
PLA |
14.8 |
± |
13.8 |
14.8 |
± |
11.5 |
-0.1 |
± |
17.4 |
||||||||||||||||||
∆VE (l·min-1) |
N+C |
4.2 |
± |
9.3 |
6.5 |
± |
6.9 |
2.4 |
± |
11.2 |
0.230 |
0.310 |
|||||||||||||||
PLA |
5.9 |
± |
9.5 |
5.2 |
± |
7.2 |
-0.7 |
± |
8.4 |
||||||||||||||||||
∆SpO2 (%) |
N+C |
76.1 |
± |
6.2 |
77.8 |
± |
9.1 |
1.7 |
± |
6.7 |
0.350 |
0.150 |
|||||||||||||||
PLA |
73.7 |
± |
9.7 |
73.9 |
± |
10.5 |
0.3 |
± |
11.5 |
||||||||||||||||||
∆TSI% |
Cerebral |
N+C |
-13.6 |
± |
27.4 |
-7.6 |
± |
3.3 |
-1.4 |
± |
10.1 |
0.198 |
0.737 |
||||||||||||||
PLA |
-8.7 |
± |
6.8 |
-5.4 |
± |
4.8 |
3.3 |
± |
4.4 |
||||||||||||||||||
Muscle |
N+C |
-0.6 |
± |
5.3 |
0.4 |
± |
10.5 |
-3.1 |
± |
5.1 |
0.788 |
0.393 |
|||||||||||||||
PLA |
-0.9 |
± |
2.9 |
-3.5 |
± |
1.9 |
-2.6 |
± |
3.4 |
Data are presented as mean ± SD, n = 24 (n = 23 for TSI). Hypoxia corresponded to an inspiratory oxygen fraction of 11%. ∆HR, heart rate difference between normoxia and hypoxia; ∆VE, minute ventilation difference between normoxia and hypoxia; ∆SpO2, pulse oxygen saturation difference between normoxia and hypoxia; ∆TSI, tissue saturation index difference between normoxia and hypoxia; PRE, measure before the supplementation period; POST, measure after the supplementation period; N+C, nitrate + citrulline; PLA, placebo; ∆PRE/POST, difference between PRE and POST measures; p∆, p value for ∆PRE/POST group comparison; d∆, Cohen’s d effect size of N+C supplementation on ∆PRE/POST.