Table 2.
Blood variables during knee-extensor exercise
| Blood variable | 6 W | 12 W | 40% Wmax | |||
|---|---|---|---|---|---|---|
| CON | SILD | CON | SILD | CON | SILD | |
| Young | ||||||
| PO2 (mmHg) | ||||||
| a | 107 ± 3 | 102 ± 2* | 103 ± 3 | 102 ± 2 | 104 ± 2 | 103 ± 2 |
| v | 26 ± 1 | 25 ± 1 | 25 ± 1 | 25 ± 1 | 25 ± 1 | 25 ± 1 |
| Hemoglobin (g dL−1) | ||||||
| a | 14.6 ± 0.2 | 14.5 ± 0.2 | 14.7 ± 0.2 | 14.7 ± 0.2 | 14.7 ± 0.3 | 14.7 ± 0.2 |
| v | 14.4 ± 0.3 | 14.2 ± 0.3 | 14.4 ± 0.2 | 14.1 ± 0.2 | 14.2 ± 0.3 | 14.2 ± 0.3 |
| O2 saturation (%) | ||||||
| a | 98.2 ± 0.1 | 98.0 ± 0.1 | 98.1 ± 0.1 | 97.9 ± 0.1 | 98.1 ± 0.1 | 98.0 ± 0.1 |
| v | 40.7 ± 2.3 | 39.8 ± 1.2 | 38.9 ± 2.1 | 40.1 ± 1.4 | 38.2 ± 1.8 | 38.5 ± 1.5 |
| O2 content (mL L−1) | ||||||
| a | 195 ± 2 | 194 ± 3 | 196 ± 3 | 195 ± 3 | 196 ± 3 | 196 ± 3 |
| v | 80 ± 6 | 77 ± 3 | 76 ± 5 | 77 ± 3 | 74 ± 5 | 74 ± 3 |
| Lactate (mmol L−1) | ||||||
| a | 1.5 ± 0.3 | 1.2 ± 0.2 | 1.8 ± 0.4 | 1.3 ± 0.3 | 2.1 ± 0.4 | 1.6 ± 0.4 |
| v | 2.2 ± 0.5 | 1.5 ± 0.3* | 2.4 ± 0.6 | 1.5 ± 0.4* | 2.6 ± 0.6 | 2.1 ± 0.6 |
| Lactate release (mmol min−1) | ||||||
| 1.1 ± 0.3 | 0.5 ± 0.3* | 1.2 ± 0.6 | 0.4 ± 0.4* | 1.2 ± 0.7 | 1.1 ± 0.6 | |
| pH | ||||||
| a | 7.394 ± 0.007 | 7.393 ± 0.005 | 7.384 ± 0.006 | 7.396 ± 0.004 | 7.380 ± 0.005 | 7.394 ± 0.007* |
| v | 7.304 ± 0.011 | 7.327 ± 0.005* | 7.296 ± 0.012 | 7.320 ± 0.010* | 7.289 ± 0.011 | 7.306 ± 0.012* |
| Heart rate (beats per minute) | ||||||
| 89 ± 7 | 87 ± 5 | 94 ± 8 | 94 ± 6 | 99 ± 6 | 100 ± 6 | |
| FVP (mmHg) | ||||||
| 18.4 ± 0.9 | 17.4 ± 1.2 | 17.6 ± 1.0 | 17.3 ± 1.0 | 17.5 ± 0.8 | 18.0 ± 1.0 | |
| Older | ||||||
| PO2 (mmHg) | ||||||
| a | 85 ± 4† | 76 ± 3*† | 83 ± 3† | 77 ± 3† | 80 ± 4† | 78 ± 4† |
| v | 25 ± 1 | 23 ± 0** | 24 ± 1 | 22 ± 1 | 23 ± 1 | 22 ± 1 |
| Hemoglobin (g dL−1) | ||||||
| a | 13.6 ± 0.3† | 13.3 ± 0.4*† | 13.7 ± 0.4† | 13.5 ± 0.3† | 13.5 ± 0.3† | 13.3 ± 0.4† |
| v | 13.4 ± 0.3† | 13.1 ± 0.4† | 13.3 ± 0.4† | 13.0 ± 0.3† | 13.6 ± 0.3 | 13.3 ± 0.3 |
| O2 saturation (%) | ||||||
| a | 96.1 ± 0.3† | 94.8 ± 0.4*† | 95.9 ± 0.3† | 94.9 ± 0.5*† | 95.5 ± 0.5† | 95.1 ± 0.6† |
| v | 37.0 ± 1.8 | 33.1 ± 1.5*† | 33.3 ± 1.7† | 30.1 ± 2.2*† | 31.2 ± 2.2† | 28.5 ± 2.0† |
| O2 content (mL L−1) | ||||||
| a | 177 ± 4† | 172 ± 5*† | 178 ± 5† | 174 ± 6*† | 176 ± 4† | 172 ± 5*† |
| v | 67 ± 3† | 59 ± 3*† | 60 ± 3*† | 53 ± 4† | 57 ± 4† | 51 ± 4*† |
| Lactate (mmol L−1) | ||||||
| a | 1.2 ± 0.2 | 1.0 ± 0.1 | 1.2 ± 0.1 | 1.1 ± 0.1 | 1.2 ± 0.1 | 1.1 ± 0.1 |
| v | 1.5 ± 0.2 | 1.2 ± 0.1 | 1.4 ± 0.2 | 1.2 ± 0.1 | 1.6 ± 0.2 | 1.4 ± 0.2 |
| Lactate release (mmol min−1) | ||||||
| 0.6 ± 0.1 | 0.4 ± 0.2 | 0.5 ± 0.2 | 0.3 ± 0.2 | 0.7 ± 0.3 | 0.7 ± 0.3 | |
| pH | ||||||
| a | 7.413 ± 0.006† | 7.421 ± 0.005† | 7.412 ± 0.005† | 7.424 ± 0.006† | 7.410 ± 0.008† | 7.431 ± 0.005*† |
| v | 7.336 ± 0.007† | 7.350 ± 0.004* | 7.337 ± 0.005† | 7.342 ± 0.006 | 7.333 ± 0.006† | 7.339 ± 0.006† |
| Heart rate (beats per minute) | ||||||
| 74 ± 5 | 74 ± 5 | 78 ± 5 | 79 ± 6 | 82 ± 6 | 81 ± 6 | |
| FVP (mmHg) | ||||||
| 19.7 ± 1.6 | 19.0 ± 1.8 | 19.7 ± 1.8 | 19.8 ± 1.9 | 20.2 ± 1.8 | 19.7 ± 1.9 | |
a, femoral arterial; v, femoral venous.
*
Significant difference from CON within same condition (P < 0.05).
†
Significant difference from young within same condition (P < 0.05).