6 months | 15 months | Difference (95% CI) | p value* | |
---|---|---|---|---|
V˙o2, oxygen consumption; V˙e, minute ventilation; HR, heart rate; RER, respiratory exchange ratio; RR, respiratory rate; O2 pulse, oxygen consumption per heart beat; V˙e/V˙o2, V˙e/V˙co2, ventilatory equivalent for oxygen and carbon dioxide; Peto2, Petco2, end tidal oxygen and carbon dioxide partial pressures; VAT, ventilatory anaerobic threshold; OUES, oxygen uptake efficiency slope. | ||||
*Paired t test. | ||||
Height (cm) | 160.6 (2.5) | 162.3 (2.4) | 1.7 (1.0 to 2.4) | <0.0005 |
Weight (kg) | 56.7 (2.6) | 58.3 (2.6) | 1.6 (0.4 to 2.8) | 0.008 |
BMI (kg/m2) | 21.8 (0.7) | 22.0 (0.8) | 0.2 (−0.2 to 0.6) | 0.313 |
Resting V˙o2 (ml/min) | 228.3 (11.3) | 233.6 (14.9) | 5.3 (−22.8 to 33.4) | 0.702 |
Respiratory quotient | 0.86 (0.01) | 0.83 (0.02) | −0.03 (−0.06 to 0.00) | 0.062 |
Resting HR (beats/min) | 87.3 (2.4) | 81.5 (2.7) | −5.8 (−11.0 to −0.6) | 0.032 |
Resting RR (breaths/min) | 19.7 (0.9) | 19.1 (0.9) | −0.63 (−2.1 to 0.8) | 0.376 |
Resting V˙e (l/min) | 9.1 (0.3) | 8.3 (0.4) | −0.9 (−1.76 to 0.02) | 0.058 |
Peak V˙o2 (ml/min) | 1595.6 (127.5) | 1780.4 (95.6) | 112.8 (−60.4 to 286.0) | 0.192 |
Peak V˙o2 (ml/kg/min) | 28.0 (1.7) | 29.6 (1.2) | 1.6 (−1.6 to 4.8) | 0.306 |
Peak RER | 1.2 (0.0) | 1.2 (0.0) | 0.00 (−0.04 to 0.05) | 0.861 |
Peak HR (beats/min) | 192.8 (1.7) | 190.8 (1.6) | −2.0 (−4.9 to 0.8) | 0.153 |
Peak O2 pulse (ml/beat) | 8.3 (0.7) | 8.9 (0.5) | 0.6 (−0.4 to 1.6) | 0.217 |
Peak RR (breaths/min) | 51.0 (2.2) | 46.6 (2.0) | −4.4 (−8.1 to −0.7) | 0.022 |
Peak V˙e (l/min) | 70.5 (3.4) | 61.3 (3.7) | −9.1 (−16.5 to −1.8) | 0.017 |
Peak V˙e/V˙o2 (mm Hg) | 47.8 (2.3) | 36.2 (1.0) | −11.6 (−15.7 to −7.4) | <0.0005 |
Peak V˙e/V˙co2 (mm Hg) | 39.8 (2.0) | 30.0 (0.8) | −9.9 (−13.3 to −6.4) | <0.0005 |
Peto2 (mm Hg) | 95.2 (3.1) | 113.3 (0.9) | 18.1 (10.7 to 25.5) | <0.0005 |
Petco2 (mm Hg) | 32.7 (1.7) | 40.2 (1.0) | 7.5 (4.9 to 10.1) | <0.0005 |
VAT (ml/min) | 964.5 (77.9) | 1028.4 (54.4) | 63.9 (−62.5 to 190.2) | 0.308 |
OUES | 711.1 (66.8) | 822.5 (42.1) | 111.4 (16.6 to 206.1) | 0.023 |
Exercise time (s) | 626.7 (24.1) | 557.9 (17.6) | −68.8 (−111.8 to −25.7) | 0.003 |