Table 4.
Linear Mixed Models for Substituting Awake Sedentary Boutsa with Higher-intensity Physical Activity and Cardiometabolic Risk Factors
| WC (cm) b | SBP (mm Hg) | DBP (mm Hg) | Log glucose (mg/dL) | Log TG (mg/dL) | Log HDL-C (mg/dL) | Log insulin (μIU/mL) | Log HOMA-IR | |||
|---|---|---|---|---|---|---|---|---|---|---|
| N = 533, # obs. = 932 | N = 533, # obs. = 931 | N = 533, # obs. = 931 | N = 390, # obs. = 683 | N = 390, # obs. = 683 | N = 390, # obs. = 683 | N = 390, # obs. = 683 | N = 390, # obs. = 683 | |||
| ▪ 1 visit (n = 134,25.14%) | ▪ 1 visit (n = 135,25.33%) | ▪ 1 visit (n = 135,25.33%) | ▪ 1 visit (n = 97,24.87%) | ▪ 1 visit (n = 97,24.87%) | ▪ 1 visit (n = 97,24.87%) | ▪ 1 visit (n = 97,24.87%) | ▪ 1 visit (n = 97,24.87%) | |||
| ▪ 2 visits (n = 399,74.86%) | ▪ 2 visits (n = 398,74.67%) | ▪ 2 visits (n = 398,74.67%) | ▪ 2 visits (n = 293,75.13%) | ▪ 2 visits (n = 293,75.13%) | ▪ 2 visits (n = 293,75.13%) | ▪ 2 visits (n = 293,75.13%) | ▪ 2 visits (n = 293,75.13%) | |||
| Substituting sedentary bout duration with light activity (minutes/ day) | Crude modelc | β | 0.07 | 0.17* | 0.02 | 0.0021* | −0.0047 | 0.0008 | −0.0108* | − 0.0078 |
| Back transformed β | – | – | – | 0.21% | −0.47% | 0.08% | −1.07% | −0.78% | ||
| 95% CI | (−0.02, 0.16) | (0.07, 0.26) | (−0.05, 0.09) | (0.0007, 0.0035) | (−0.0099, 0.0004) | (−0.0013, 0.0028) | (− 0.0165, − 0.0051) | (−0.014, − 0.0016) | ||
| Adjusted modelc | β | −0.01 | 0.05 | −0.04 | 0.0012 | −0.0035 | 0.0013 | −0.0087* | −0.0075 | |
| Back transformed β | – | – | – | 0.12% | −0.35% | 0.13% | −0.87% | −0.75% | ||
| 95% CI | (−0.05, 0.03) | (−0.05, 0.15) | (− 0.12, 0.03) | (− 0.0003, 0.0027) | (−0.0088, 0.0019) | (− 0.0008, 0.0034) | (− 0.0146, − 0.0028) | (−0.0139, − 0.0011) | ||
| Substituting sedentary bout duration with MVPA activity | Crude modeld | β | −0.29* | −0.14 | − 0.09 | −0.0006 | − 0.0097 | 0.0013 | − 0.0107 | −0.0125 |
| (minutes/ day) | Back transformed β | – | – | – | −0.06% | −0.97% | 0.13% | −1.06% | −1.24% | |
| 95% CI | (−0.47, − 0.12) | (− 0.32, 0.05) | (−0.23, 0.05) | (− 0.0033, 0.0021) | (− 0.0189, − 0.0005) | (−0.0024, 0.005) | (− 0.0211, − 0.0003) | (−0.0238, − 0.0013) | ||
| Adjusted modeld | β | −0.07 | − 0.12 | −0.07 | − 0.0005 | −0.0079 | 0.0022 | −0.0085 | − 0.0089 | |
| Back transformed β | – | – | – | −0.05% | −0.79% | 0.22% | −0.85% | − 0.89% | ||
| 95% CI | (−0.1454, 0.0004) | (− 0.3, 0.05) | (− 0.21, 0.06) | (−0.0031, 0.0022) | (− 0.0171, 0.0013) | (− 0.0015, 0.0059) | (−0.0188, 0.0019) | (− 0.0201, 0.0022) | ||
| Substituting sedentary bout frequency with light activity (count/day) | Crude modele | β | 0.5 | 1.18* | 0.17 | 0.0145* | −0.0348 | 0.0061 | −0.075* | −0.0541 |
| Back transformed β | – | – | – | 0.01% | −3.42% | 0.61% | −7.23% | −5.27% | ||
| 95% CI | (−0.14, 1.14) | (0.53, 1.83) | (−0.32, 0.65) | (0.0045, 0.0245) | (−0.0703, 0.0008) | (−0.0082, 0.0204) | (− 0.1147, − 0.0352) | (−0.0975, − 0.0108) | ||
| Adjusted modele | β | −0.11 | 0.35 | −0.32 | 0.0074 | −0.0248 | 0.0081 | −0.0585* | −0.0515 | |
| Back transformed β | – | – | – | 0.74% | −2.45% | 0.81% | −5.68% | −5.02% | ||
| 95% CI | (−0.38, 0.16) | (−0.3, 1.01) | (− 0.81, 0.18) | (− 0.0031, 0.0180) | (−0.0618, 0.0122) | (− 0.0067, 0.0228) | (− 0.0996, − 0.0173) | (−0.0961, − 0.0069) | ||
| Substituting sedentary bout frequency with MVPA activity (count/day) | Crude modelf | β | −2.12* | −1 | −0.58 | −0.0031 | − 0.0717 | 0.0126 | − 0.0604 | −0.0736 |
| Back transformed β | – | – | – | −0.31% | −6.92% | 1.27% | −5.86% | −7.10% | ||
| 95% CI | (−3.35, −0.9) | (−2.3, 0.31) | (−1.55, 0.39) | (−0.0215, 0.0153) | (− 0.1358, − 0.0076) | (−0.0134, 0.0386) | (− 0.1331, 0.0124) | (− 0.1521, 0.0048) | ||
| Adjusted modelf | β | −0.54 | −0.88 | − 0.44 | −0.0034 | − 0.0584 | 0.0203 | − 0.0429 | −0.0467 | |
| Back transformed β | – | – | – | −0.34% | −5.67% | 2.05% | −4.20% | −4.56% | ||
| 95% CI | (−1.05, −0.03) | (−2.13, 0.38) | (− 1.39, 0.51) | (− 0.0217, 0.0149) | (− 0.1228, 0.006) | (−0.0056, 0.0462) | (− 0.1152, 0.0295) | (− 0.1247, 0.0314) | ||
aA bout was defined as 5 minutes of uninterrupted time performing a specific activity intensity. Within a bout, we allowed for up to 30-second of change in the physical activity intensity before terminating the bout
bWaist circumference models were additionally adjusted for body mass index
cCrude model includes bout duration spent in sedentary and light physical activity, and adjusted model was adjusted for mother’s enrollment in the calcium intervention study, parity status, child’s age, sex, total time of physical activity, and pubertal onset
dCrude model includes bout duration spent in sedentary and MVPA physical activity, and adjusted model was adjusted for mother’s enrollment in the calcium intervention study, parity status, child’s age, sex, total time of physical activity, and pubertal onset
eCrude model includes bout frequency spent in sedentary and light physical activity, and adjusted model was adjusted for mother’s enrollment in the calcium intervention study, parity status, child’s age, sex, total time of physical activity, and pubertal onset
fCrude model includes bout frequency spent in sedentary and MVPA physical activity, and adjusted model was adjusted for mother’s enrollment in the calcium intervention study, parity status, child’s age, sex, total time of physical activity, and pubertal onset
* p < 0.00625
** p < 0.0001
Back-transformed β is expressed as a percentage of change
Abbreviations: WC Waist circumference, SBP Systolic blood pressure, DBP Diastolic blood pressure, TG Triglycerides, HDL-C High density lipoprotein cholesterol, HOMA-IR Homeostatic model assessment of insulin resistance