Table 1. Participant Characteristics by Tertiles of MVPA.
| Characteristic | Participants, No. (%) | P value | ||
|---|---|---|---|---|
| MVPA tertile 1 (n = 2535)a | MVPA tertile 2 (n = 2533)b | MVPA tertile 3 (n = 2539)c | ||
| Baseline d | ||||
| Age, mean (SD), y | 68.2 (7.7) | 62.6 (7.7) | 60.0 (7.8) | <.001 |
| Sex | ||||
| Male | 880 (34.7) | 1160 (45.8) | 1422 (56.0) | <.001 |
| Female | 1655 (65.3) | 1373 (54.2) | 1117 (44.0) | |
| Race | ||||
| Black | 1061 (41.9) | 790 (31.2) | 556 (21.9) | <.001 |
| White | 1474 (58.1) | 1743 (68.8) | 1983 (78.1) | |
| Region of residencee | ||||
| Non–stroke belt or non–stroke buckle | 1118 (44.1) | 1097 (43.3) | 1231 (48.5) | .001 |
| Stroke buckle | 550 (21.7) | 542 (21.4) | 546 (21.5) | |
| Stroke belt | 867 (34.2) | 894 (35.3) | 762 (30.0) | |
| Educational level | ||||
| <High school | 246 (9.7) | 134 (5.3) | 71 (2.8) | <.001 |
| High school graduate | 730 (28.8) | 580 (22.9) | 386 (15.2) | |
| Some college | 740 (29.2) | 704 (27.8) | 574 (22.6) | |
| College graduate | 816 (32.2) | 1114 (44.0) | 1506 (59.3) | |
| Current smoker | 352 (13.9) | 268 (10.6) | 178 (7.0) | <.001 |
| Alcohol consumptionf | ||||
| None | 1723 (68.0) | 1396 (55.1) | 1127 (44.4) | <.001 |
| Moderate | 715 (28.2) | 1013 (40.0) | 1267 (49.9) | |
| Heavy | 96 (3.8) | 124 (4.9) | 145 (5.7) | |
| BMI, mean (SD) | 29.7 (6.6) | 28.8 (5.5) | 27.1 (4.8) | <.001 |
| Diabetesg | 563 (22.2) | 314 (12.4) | 193 (7.6) | <.001 |
| Hypertensionh | 1635 (64.5) | 1259 (49.7) | 939 (37.0) | <.001 |
| Left ventricular hypertrophy | 279 (11.0) | 1646 (65.0) | 140 (5.5) | <.001 |
| Atrial fibrillation | 220 (8.7) | 144 (5.7) | 107 (4.2) | <.001 |
| History of CHD | 408 (16.1) | 296 (11.7) | 226 (8.9) | <.001 |
| Accelerometer | ||||
| Age at time of accelerometer testing, mean (SD), y | 73.7 (8.8) | 68.8 (7.9) | 66.2 (8.0) | <.001 |
| Season accelerometer worni | ||||
| Summer | 598 (23.6) | 654 (25.8) | 655 (25.8) | .16 |
| Autumn | 618 (24.4) | 623 (24.6) | 620 (24.4) | |
| Winter | 612 (24.1) | 557 (22.0) | 571 (22.5) | |
| Spring | 697 (27.5) | 699 (27.6) | 693 (27.3) | |
| Wear time, mean (SD), min/d | 865.7 (105.6) | 892.1 (101.0) | 915.4 (93.5) | <.001 |
| Valid wear days | ||||
| 4-5 | 357 (14.1) | 276 (10.9) | 170 (6.7) | <.001 |
| 6-7 | 2178 (85.9) | 2257 (89.1) | 2369 (93.3) | |
| Sedentary time, mean (SD), min/dj | 803.0 (63.8) | 736.3 (64.3) | 681.9 (73.4) | <.001 |
| Sedentary bout duration, mean (SD), min/boutk | 15.4 (12.1) | 9.8 (3.3) | 8.8 (2.9) | <.001 |
| LIPA, mean (SD), min/dl | 135.3 (62.7) | 201.3 (64.1) | 235.2 (69.7) | <.001 |
| MVPA, mean (SD), min/dm | 1.1 (1.1) | 7.1 (3.1) | 32.9 (19.4) | <.001 |
| Bouted MVPA, mean (SD), min/dn | 0 | 1.3 (2.6) | 16.0 (17.5) | <.001 |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); CHD, coronary heart disease; LIPA, light-intensity physical activity; MVPA, moderate- to vigorous-intensity physical activity.
SI conversion factor: To convert fasting glucose from mg/dL to mmol/L, multiply by 0.0555.
Tertile 1 cutoff point was less than 2.7 minutes/day.
Tertile 2 cutoff point was at least 2.7 to less than 14.0 minutes/day.
Tertile 3 cutoff point was at least 14.0 minutes/day.
Demographic data, cardiovascular risk factors, chronic disease status, and medical history data were collected at the original baseline.
The stroke buckle includes the coastal plain region of Georgia, North Carolina, and South Carolina. The stroke belt includes the remainder of Georgia, North Carolina, and South Carolina plus Alabama, Arkansas, Louisiana, Mississippi, and Tennessee.
None indicates 0 drinks/week; moderate, >0 to 14 drinks/week for men and more than 0 to 7 drinks/week for women; and heavy, more than 14 drinks/week for men and >7 drinks/week for women.
Diabetes was defined as a fasting glucose of at least 126 mg/dL (or at least 200 mg/dL if the participant did not fast) or self-reported use of medications for glucose control.
Hypertension was determined as the mean of 2 blood pressure measures taken after 5 minutes of seated rest and defined as systolic blood pressure of at least 140 mm Hg, diastolic blood pressure of at least 90 mm Hg, or self-reported current use of antihypertensive medication.
Summer was defined as June 21 to September 20; autumn, September 21 to December 20; winter, December 21 to March 20; and spring, March 21 to June 20.
Sedentary time was defined as minutes in which the accelerometer registered less than 50 counts/minute. It was corrected for wear time and expressed as estimated minutes/day of sedentary time given a standardized 16 hours of accelerometer wear.
Sedentary bout was defined as consecutive minutes in which the accelerometer registered less than 50 counts/minute.
LIPA was defined as minutes in which the accelerometer registered 50 to 1064 counts/minute.
MVPA was defined as minutes in which the accelerometer registered at least 1065 counts/minute.
Bouted MVPA was defined as at least 10 minutes of consecutive accelerometer readings of at least 1065 counts/minute, allowing for 1- to 2-minute decreases below threshold.