Table 2.
Participant Characteristics at Year 20 by Physical Activity Quartiles, the CARDIA Study, 2005–2006 (N=1922)
| Characteristics | Quartiles of Physical Activity* | P Value† | |||
|---|---|---|---|---|---|
| Q1 ≤333 Min/Day (N=480) | Q2 334 to 391 Min/Day (N=481) | Q3 392 to 454 Min/Day (N=481) | Q4 ≥455 Min/Day (N=480) | ||
| Age, y | 45.5±3.5 | 45.3±3.7 | 45.2±3.4 | 45.2±3.5 | 0.100 |
| Female, n (%) | 250 (52.1) | 191 (39.7) | 155 (32.2) | 203 (42.3) | <0.001 |
| White, n (%) | 313 (65.2) | 277 (57.6) | 305 (63.4) | 248 (51.7) | <0.001 |
| Education, y | 15.8±2.5 | 15.5±2.5 | 15.4±2.6 | 14.5±2.4 | <0.001 |
| Unemployment, n (%) | 55 (11.5) | 48 (10.0) | 49 (10.2) | 54 (11.3) | 0.842 |
| Health insurance, n (%) | 432 (90.0) | 437 (90.9) | 433 (90.0) | 414 (86.3) | 0.094 |
| Medication use, n (%)‡ | 99 (20.6) | 96 (20.0) | 89 (18.5) | 91 (18.0) | 0.839 |
| Smoking status, n (%) | <0.001 | ||||
| Current | 58 (12.1) | 63 (13.1) | 59 (12.3) | 102 (21.3) | |
| Former | 103 (21.5) | 93 (19.3) | 119 (24.7) | 96 (20.0) | |
| Never | 319 (66.5) | 325 (67.6) | 303 (63.0) | 282 (58.5) | |
| Alcohol consumption, mL/day | 2.4 (12.4) | 2.4 (12.7) | 2.7 (14.3) | 4.9 (17.0) | 0.011 |
| Body mass index, kg/m2 | 29.5±6.7 | 29.0±6.5 | 28.3±6.3 | 28.5±6.1 | 0.009 |
| Accelerometer measured activity, min/day§ | |||||
| Total wear time | 887.6±89.8 | 895.4±86.3 | 890.5±83.7 | 872.6±86.3 | 0.005 |
| Sedentary | 597.1±68.0 | 528.2±54.2 | 468.0±45.0 | 367.2±62.4 | <0.001 |
| LPA | 264.6±44.4 | 335.2±40.2 | 385.9±44.9 | 457.7±65.5 | <0.001 |
| MVPA | 21.6 (22.6) | 27.3 (27.8) | 31.0 (28.1) | 41.4 (38.1) | <0.001 |
| Cardiometabolic risk factors | |||||
| Waist circumference, cm | 93.7±15.7 | 90.6±14.4 | 88.0±14.1 | 89.7±13.5 | <0.001 |
| Systolic blood pressure, mm Hg | 115.4±13.3 | 113.7±13.1 | 113.5±15.1 | 114.8±13.6 | 0.446 |
| Diastolic blood pressure, mm Hg | 72.2±10.5 | 70.9±10.1 | 70.5±11.0 | 70.8±10.5 | 0.038 |
| Glucose, mg/dL | 95.6 (12.7) | 95.6 (11.7) | 94.6 (11.7) | 94.6 (12.7) | 0.008 |
| Insulin, μU/mL | 8.9 (6.6) | 8.9 (5.9) | 7.6 (5.2) | 7.6 (5.2) | <0.001 |
| Triglycerides, mg/dL | 93.0 (74.5) | 84.0 (72.0) | 84.0 (59.0) | 83.0 (61.0) | <0.001 |
| HDL‐C, mg/dL | 51.2±15.4 | 54.8±16.4 | 57.4±16.7 | 55.1±16.2 | <0.001 |
| Composite risk scoreǁ | 0.14±0.70 | 0.02±0.66 | −0.09±0.66 | −0.07±0.62 | <0.001 |
Data presented as mean±SD or median (interquartile range), unless otherwise specified. CARDIA indicates Coronary Artery Risk Development in Young Adults; HDL‐C, high‐density lipoprotein cholesterol; LPA, light‐intensity physical activity; MVPA, moderate‐to‐vigorous intensity physical activity.
Accelerometer measured light‐, moderate‐, and vigorous‐intensity physical activity, standardized for total wear time.
P‐value testing for differences across quartiles of physical activity using chi‐square test, 1‐way ANOVA, or Kruskal–Wallis test, as appropriate.
Self‐reported medication use for blood pressure, cholesterol, or diabetes mellitus.
Freedson cut‐point thresholds defined sedentary time in counts/min as <100, LPA as 100 to 1951, and MVPA as ≥1952.
Composite risk score was calculated by standardizing and summing waist circumference, average blood pressure ([systolic+diastolic]/2), log glucose, log insulin, log triglycerides, and negative HDL‐C, then dividing by 6 to create a z‐score.