Table 1.
Subject characteristics
| Young | Middle aged | Old | |
|---|---|---|---|
| n (male/female) | 15 (8/7) | 14 (8/6) | 11 (10/1) |
| Mean age (years) | 23 ± 3 | 56 ± 4 | 72 ± 3 |
| Body mass (kg/m2) | 22 ± 2 | 24 ± 3 | 25 ± 2 |
| BP (mmHg) | |||
| Systolic | 123 ± 12 | 136 ± 14a | 148 ± 17a |
| Mean | 90 ± 9 | 96 ± 8 | 101 ± 11a |
| Diastolic | 72 ± 7 | 73 ± 5 | 74 ± 8 |
| HR (beats·min−1) | 58 ± 8 | 55 ± 5 | 60 ± 6 |
| COCO‐trek (L·min−1) | 6.4 ± 0.9 | 4.9 ± 0.7a | 4.7 ± 0.8a |
| COrebreathing (L·min−1) | 7.9 ± 2.2 | 5.7 ± 1.0a | 5.8 ± 1.0a |
| Mean MCAV (cm·s−1) | 72 ± 14 | 59 ± 8a | 57 ± 15a |
| PetCO2 (mmHg) | 41 ± 4 | 41 ± 5 | 38 ± 6 |
Data are presented as mean ± SD. BP, blood pressure; HR, heart rate; CO, cardiac output; MCAV, middle cerebral artery blood flow velocity; PetCO2, end‐tidal CO2 partial pressure.
a
P < 0.05 versus young.