Table 1.
Descriptive characteristics assessed at age ≥10 years in 472 participants, Project HeartBeat!, 1991–1995
| Cohort 1 (n=212)a | Cohort 2 (n=151)b | Cohort 3 (n=109)c | ||||
|---|---|---|---|---|---|---|
|
|
|
|
||||
| Boys (n=98) | Girls (n=114) | Boys (n=74) | Girls (n=77) | Boys (n=55) | Girls (n=54) | |
| Characteristic (M [SD]) | ||||||
| Age (years) | 10.4 (0.1) | 10.4 (0.1) | 11.5 (0.3) | 11.5 (0.4) | 14.4 (0.1) | 14.4 (0.1) |
| Physical activity (MVPA) (min/day) | 84.6 (68.5) | 78.0 (81.5) | 102.5 (82.0) | 51.9 (54.9) | 91.1 (73.6) | 59.6 (80.3) |
| Energy intake (kcal/day) | 2069.1 (603.7) | 1850.7 (709.9) | 2340.1 (770.8) | 2189.6 (728.6) | 2728.3 (910.5) | 2249.5 (719.8) |
| Sedentary behaviors (min/day)d | 157.0 (125.6) | 132.5 (92.2) | 154.6 (97.3) | 162.2 (116.7) | 169.2 (104.8) | 161.0 (112.8) |
| BMI (kg/m2) | 18.6 (3.7) | 19.2 (4.2) | 19.6 (4.1) | 18.6 (3.4) | 20.3 (3.2) | 21.6 (3.3) |
| Fat free–mass index (kg/m2) | 14.2 (1.7) | 14.1 (2.0) | 14.6 (1.9) | 13.6 (1.7) | 16.4 (1.9) | 15.4 (1.4) |
| Fat mass index (kg/m2) | 4.3 (2.5) | 5.1 (2.6) | 5.0 (2.8) | 5.0 (2.3) | 3.9 (2.3) | 6.1 (2.2) |
| Race/ethnicity (n [%]) | ||||||
| Nonblack | 77 (78.6) | 85 (74.6) | 61 (82.4) | 66 (85.7) | 51 (92.7) | 50 (92.6) |
| Gender (n [%]) | 98 (46.2) | 114 (53.8) | 74 (49.0) | 77 (51.0) | 55 (50.5) | 54 (49.5) |
| Sexual maturation (n [%]) | ||||||
| Pubic-Hair Stage 1 | 84 (85.7) | 66 (57.9) | 52 (70.3) | 20 (26.0) | 2 (3.6) | 0 (0) |
| Pubic-Hair Stage 2 | 11 (11.2) | 35 (30.7) | 18 (24.3) | 36 (46.8) | 10 (18.2) | 1 (1.9) |
| Pubic-Hair Stage 3 | 3 (3.1) | 9 (7.9) | 4 (5.4) | 13 (16.9) | 10 (18.2) | 4 (7.4) |
| Pubic-Hair Stage 4 | 0 (0) | 3 (2.6) | 0 (0) | 7 (9.1) | 24 (43.6) | 22 (40.7) |
| Pubic-Hair Stage 5 | 0 (0) | 1 (0.9) | 0 (0) | 1 (1.3) | 9 (16.4) | 27 (50.0) |
a
Cohort 1: children aged ≥10 years at entry or who attained age 10 years during follow-up period
b
Cohort 2: children aged 11 years at initial assessment
c
Cohort 3: children aged 14 years at initial assessment
d
Sedentary behaviors: TV viewing, reading, and computer use
MVPA, moderate-to-vigorous physical activity