Table 3: Changes in Oxygen uptake (
), Carbon dioxide output (
), and Respiratory exchange ratio (RER) at rest and during incremental exercise at the three CO2 levels
|
Air (n=8) |
3% CO2 (n=8) |
6% CO2 (n=7) |
|
46.6 ± 4.0 |
45.7 ± 6.1 |
42.6 ± 4.7 |
(ml/min) |
Rest |
271.8 ± 57.9 |
284.6 ± 23.0 |
348.6 ± 148.8 |
|
30%
|
879.8 ± 180.9 |
873.6 ± 215.6 |
861.1 ± 155.4 |
|
45% |
1295.6 ± 301.8 |
1267.0 ± 317.9 |
1248.0 ± 182.1 |
|
60% |
1687.8 ± 259.9 |
1741.0 ± 300.9 |
1605.6 ± 220.6 |
|
80% |
2376.1 ± 405.8 |
2410.9 ± 434.6 |
2106.4 ± 373.6 |
|
90% |
2714.9 ± 459.4 |
2723.4 ± 521.3 |
2423.7 ± 389.5 |
|
Max |
3002.4 ± 532.8 |
2940.5 ± 604.9 |
2719.0 ± 447.4 |
(ml/min) |
Rest |
241.8 ± 44.4 |
218.9 ± 27.7 |
162.9 ± 37.6 |
|
30% |
729.3 ± 169.0 |
646.8 ± 167.3 |
563.9 ± 164.4 |
|
45% |
1233.1 ± 337.7 |
1052.4 ± 306.1 |
964.3 ± 175.9 |
|
60% |
1733.0 ± 298.4 |
1586.0 ± 299.7 |
1346.7 ± 201.2 |
|
80% |
2645.3 ± 491.6 |
2351.3 ± 404.6 |
1925.7 ± 408.9 *† |
|
90% |
3101.8 ± 493.0 |
2707.9 ± 565.8* |
2339.6 ± 436.6* |
|
Max |
3589.6 ± 562.5 |
2973.3 ± 765.0* |
2614.3 ± 629.2* |
RER |
Rest |
0.90 ± 0.11 |
0.77 ± 0.09* |
0.55 ± 0.16*† |
|
30% |
0.83 ± 0.07 |
0.74 ± 0.08* |
0.65 ± 0.08*† |
|
45% |
0.94 ± 0.07 |
0.83 ± 0.07* |
0.77 ± 0.05* |
|
60% |
1.03 ± 0.05 |
0.91 ± 0.05* |
0.84 ± 0.05* |
|
80% |
1.11 ± 0.04 |
0.98 ± 0.07* |
0.92 ± 0.10* |
|
90% |
1.15 ± 0.05 |
0.99 ± 0.08* |
0.97 ± 0.08* |
|
Max |
1.20 ± 0.05 |
1.01 ± 0.14* |
0.95 ± 0.13* |
Values are means ± SD. *P<0.05 vs Air.† P<0.05 vs 3% CO2 .