Table 2.
Vastus lateralis electromyographic variables in response to sprint exercise performed at the end of an incremental exercise to exhaustion in normoxia (PIO2 ≈ 143 mmHg) and severe hypoxia (PIO2 ≈ 73 mmHg), after 10 or 60 s of occlusion of the circulation.
| Control sprint | Nx10s | Nx60s | Hyp10s | Hyp60s | Main Oxy (P) | Main Occ (P) | Interaction Oxy × Occ (P) | |
|---|---|---|---|---|---|---|---|---|
| RMSraw (μV) | 238.1±82.0a | 153.2±64.7 | 137.1±53.2 | 160.2±68.7 | 161.8±61.8 | 0.220 | 0.706 | 0.429 |
| RMSNz (A.U.) | 475.1±155.2a | 317.3±95.1 | 254.6±110.0 | 344.2±126.4c | 317.0±172.4 | 0.112 | 0.059 | 0.436 |
| Burst (ms) | 331.9±24.6b,d | 299.7±22.7c | 324.6±27.7 | 305.5±23.8c | 337.3±34.4b,d | 0.026 | 0.001 | 0.381 |
| TAINz (A.U.) | 1023.1±340.6a | 600.8±268.8 | 581.5±244.2 | 642.9±297.0 | 715.8±288.2 | 0.12 | 0.729 | 0.326 |
| MPF (Hz) | 93.9±9.7b,c | 81.9±14.2 | 79.5±16.4 | 86.3±20.3 | 89.5±17.2 | 0.006 | 0.837 | 0.212 |
| MdPF (Hz) | 80.2±6.0b,c,d | 66.4±9.4e | 67.0±13.6 | 71.4±16.6 | 74.7±13.9c | 0.011 | 0.255 | 0.500 |
P < 0.05 compared with the other conditions.
P < 0.05 compared with Nx10s.
P < 0.05 compared with Nx60s.
P < 0.05 compared with Hyp10s.
P < 0.05 compared with Hyp60s.
RM ANOVA (2 × 2) Main Oxy: main oxygenation effect due to the conditions in which was performed the incremental exercise test (Nx, Normoxia; Hyp, hypoxia); RM ANOVA (2 × 2) Main Occ, Main Occlusion effect due to the duration of the occlusion (10 vs. 60 s); Wpeak-i, instantaneous peak power in the sprint; Wmean, mean power in the 10 s sprint; RMSraw, raw root mean square; RMSNz, Normalized root mean square; Burst, burst duration; TAINz, Normalized total activation index (arbitrary units, A.U.); MPF, mean power frequency; MdPF, median power frequency.