Association of sedentary behaviour and physical activity with cardiometabolic health in Japanese adults

Abstract

Although the Asian population exhibits excessive sedentary behaviour and has a high susceptibility to metabolic syndrome (MetS), the nature of these associations remains unclear. This study aimed to investigate the association of sedentary time with cardiometabolic health and examine the association of reallocating sedentary time to light physical activity (LPA) or moderate-vigorous physical activity (MVPA) on cardiometabolic health in Japanese adults. A cross-sectional study was performed using data obtained from 758 Japanese adults. We assessed sedentary time, LPA, and MVPA using an accelerometer. Linear and logistic regression models were used to analyse the association between sedentary time and cardiometabolic risk factors. An isotemporal substitution model was used to estimate the theoretical influence of reallocating sedentary time to LPA or MVPA. A longer sedentary time was associated with worse cardiometabolic health, including MetS. Reallocating 30 min of sedentary time to LPA was significantly associated with lower body mass index, visceral fat, insulin resistance, triglyceride, and MetS levels and increased muscle mass and HDL-C (all P < 0.05). Reallocating 30 min of sedentary time to MVPA was strongly associated with the aforementioned factors. These results demonstrate the potential beneficial effects of reallocating sedentary time to LPA and MVPA on cardiometabolic health of Asians.

Figure 1

Isotemporal substitution of sedentary time with LPA or MVPA on cardiometabolic risk factors. The values shown are β (95% confidence interval). Each z-score indicates the amount of change in the outcome variable associated with reallocating 30 min of sedentary time to LPA (open circle) or MVPA (closed circle). Abbreviations: BMI, body mass index; VFA, visceral fat area; SBP, systolic blood pressure; DBP, diastolic blood pressure; HOMA-IR, homeostasis model assessment of insulin resistance; TG, triglycerides; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol. Linear regressions models were used to assess isotemporal substitution of sedentary time with LPA or MVPA, with adjustment for age, sex, smoking status, alcohol intake, energy intake, and accelerometer wear time. ^aLog-transformed value was used. The MetS score was calculated by standardising and summing VFA, blood pressure ([SBP + DBP]/2), log glucose, log TG, and inverse HDL-C. *P < 0.05, **P < 0.01, ***P < 0.001.