Table 1. Baseline Characteristics of Men and Women Stratified by Fitness Level.
| MEN (n=1170) | ||||
|---|---|---|---|---|
| Low Fitness (n=336) |
Intermediate Fitness (n=494) |
High Fitness (n=340) |
P trend | |
| Age (years) | 19.6 (±8.6) | 22.0 (±10.1) | 26.4 (±10.8) | <.001 |
| BMI (kg/m2) | 26.8 (±6.5) | 24.0 (±5.1) | 24.9 (±5.1) | <.001 |
| SBP (mm Hg) | 115.5 (±10.6) | 113.3 (±11.2) | 115.3 (±10.7) | .58 |
| DBP (mm Hg) | 63.3 (±13.6) | 62.5 (±13.8) | 65.3 (±13.1) | .07 |
| Total cholesterol (mg/dL) | 173.5 (±40.1) | 171.9 (±39.6) | 178.0 (±40.2) | .15 |
| HDL cholesterol (mg/dL) | 48.0 (±11.6) | 50.7 (±12.8) | 52.2 (±13.9) | <.001 |
| Fasting glucose (mg/dL) | 96.1 (±27.1) | 94.3 (±18.7) | 92.6 (±10.5) | 0.16 |
| Current smoking (n)* | 62 (19.2) | 104 (22.2) | 94 (28.1) | .006 |
| Wear time (hours/day) | 14.1 (±2.1) | 14.2 (±2.0) | 14.3 (±1.9) | .06 |
| Wear time (days) | 4.6 (±1.9) | 4.8 (±1.9) | 4.9 (±1.9) | .11 |
| Sedentary time (hours/day) | 7.0 (±2.3) | 6.5 (±2.4) | 6.4 (±2.3) | <.001 |
| Moderate & Vigorous Activity time (hours/day) | 0.20 (±0.31) | 0.31 (±0.41) | 0.33 (±0.37) | <.001 |
| Estimated VO2 max (mL/kg/min) | 35.7 (±3.7) | 43.8 (±4.6) | 53.5 (±10.8) | <.001 |
| WOMEN (n=1053) | ||||
|---|---|---|---|---|
| Low Fitness (n=364) |
Intermediate Fitness (n=372) |
High Fitness (n=371) |
P trend | |
| Age (years) | 19.4 (±8.3) | 21.5 (±9.8) | 26.9 (±11.4) | <.001 |
| BMI (kg/m2) | 26.3 (±7.2) | 24.5 (±5.7) | 25.2 (±6.0) | .14 |
| SBP (mm Hg) | 108.3 (±10.6) | 107.6 (±10.6) | 108.9 (±11.6) | .84 |
| DBP (mm Hg) | 63.2 (±10.6) | 63.7 (±10.8) | 65.3 (±11.3) | .01 |
| Total cholesterol (mg/dL) | 170.7 (±34.4) | 173.5 (±36.0) | 178.9 (±36.0) | .002 |
| HDL cholesterol (mg/dL) | 56.8 (±13.9) | 58.0 (±13.9) | 58.0 (±15.1) | .20 |
| Current smoking (n)* | 41 (12.0) | 51 (14.4) | 72 (23.9) | <.001 |
| Fasting glucose (mg/dL) | 89.5 (±11.7) | 88.9 (±7.5) | 89.6 (±15.0) | .51 |
| Wear time (hours/day) | 13.9 (±1.8) | 14.0 (±1.8) | 13.9 (±1.7) | .86 |
| Wear time (days) | 4.8 (±1.9) | 4.5 (±2.0) | 4.9 (±1.9) | .48 |
| Sedentary time (hours/day) | 7.3 (±2.1) | 7.1 (±2.1) | 6.6 (±2.1) | <.001 |
| Moderate & Vigorous Activity time (hours/day) | 0.09 (±0.18) | 0.14 (±0.23) | 0.15 (±0.22) | <.001 |
| Estimated VO2 max (mL/kg/min) | 30.1 (±3.6) | 36.5 (±4.3) | 46.3 (±9.7) | <.001 |
Means ± standard deviations for continuous variables
Current smoking shown as n (percent of respondents); missing responses in 44 men and 55 women.
Low level of cardiovascular fitness is defined as an estimated VO2 max below the 20th percentile of the ACLS data for the same gender and age; moderate fitness is defined as a value between the 20th and 59th percentile, and high fitness is defined as at or above the 60th percentile. For adolescents 12-19 years, standards are based on criteria from the FITNESSGRAM program. BMI is body mass index. SBP and DBP are baseline, resting systolic and diastolic blood pressure, respectively. HDL is high-density lipoprotein. VO2 max is the maximal oxygen consumption, as estimated by the submaximal treadmill test.