Replacement of Sedentary Time with Physical Activity: Effect on Lipoproteins

An approach to assess and adjust for the influence of multicollinear covariates on metabolomics association patterns-applied to a study of the associations between a comprehensive lipoprotein profile and the homeostatic model assessment of insulin resistance

INTRODUCTION

Comprehensive lipoprotein profiling using proton nuclear magnetic resonance (NMR) spectroscopy of serum represents an alternative to the homeostatic model assessment of insulin resistance (HOMA-IR). Both adiposity and physical (in)activity associate to insulin resistance, but quantification of the influence of these two lifestyle related factors on the association pattern of HOMA-IR to lipoproteins suffers from lack of appropriate methods to handle multicollinear covariates.

OBJECTIVES

We aimed at (i) developing an approach for assessment and adjustment of the influence of multicollinear and even linear dependent covariates on regression models, and (ii) to use this approach to examine the influence of adiposity and physical activity on the association pattern between HOMA-IR and the lipoprotein profile.

METHODS

For 841 children, lipoprotein profiles were obtained from serum proton NMR and physical activity (PA) intensity profiles from accelerometry. Adiposity was measured as body mass index, the ratio of waist circumference to height, and skinfold thickness. Target projections were used to assess and isolate the influence of adiposity and PA on the association pattern of HOMA-IR to the lipoproteins.

RESULTS

Adiposity explained just over 50% of the association pattern of HOMA-IR to the lipoproteins with strongest influence on high-density lipoprotein features. The influence of PA was mainly attributed to a strong inverse association between adiposity and moderate and high-intensity physical activity.

CONCLUSION

The presented covariate projection approach to obtain net association patterns, made it possible to quantify and interpret the influence of adiposity and physical (in)activity on the association pattern of HOMA-IR to the lipoprotein features.

Patterns and demographic correlates of domain-specific physical activities and their associations with dyslipidaemia in China: a multiethnic cohort study

OBJECTIVE

To evaluate the patterns and demographic correlates of domain-specific physical activities (PAs) and their associations with dyslipidaemia among ethnic minorities in China.

DESIGN

Cross-sectional.

PARTICIPANTS

In total, 17 081 individuals were included.

PRIMARY AND SECONDARY OUTCOME MEASURES

Domain-specific PAs were assessed using a questionnaire related to occupational, transportation, housework and leisure-time PAs. Dyslipidaemia was measured using an automatic biochemical instrument. Demographic variables were self-reported.

RESULTS

Housework accounted for most PAs in the study. Elderly people were more likely to participate in housework and leisure-time PA, whereas the mean level of PA in people with low education level and household income was high. With G3-G4 levels of occupational PA, Dong men (G4: OR=0.530, 95% CI 0.349 to 0.806), Miao women (G3: OR=0.698, 95% CI 0.524 to 0.931; G4: OR=0.611, 95% CI 0.439 to 0.850) and Bouyei women (G3: OR=0.745, 95% CI 0.566 to 0.981; G4: OR=0.615, 95% CI 0.440 to 0.860) tended to have a low risk of dyslipidaemia. With G2 levels of transportation, PA could reduce the risk of dyslipidaemia in Bouyei women (G2: OR=0.747, 95% CI 0.580 to 0.962). G2-G3 levels of leisure-time PA could reduce the risk of dyslipidaemia in Miao men (G2: OR=0.645, 95% CI 0.446 to 0.933; G3: OR=0.700, 95% CI 0.513 to 0.954). However, a high risk of dyslipidaemia was observed with G4 levels of leisure-time PA among Bouyei women (G4: OR=.353, 95% CI 1.001 to 1.905) and with transportation PA among Dong men (G4: OR=1.591, 95% CI 1.130 to 2.240).

CONCLUSION

The main PA of the ethnic minorities in Guizhou Province involved housework. Domain-specific PAs varied with demographic factors, and active domain-specific PAs were associated with a reduced risk of dyslipidaemia.

The Influence of Different Physical Activity Behaviours on the Gut Microbiota of Older Irish Adults

OBJECTIVE

A 24-hour day is made up of time spent in a range of physical activity (PA) behaviours, including sleep, sedentary time, standing, light-intensity PA (LIPA) and moderate-to-vigorous PA (MVPA), all of which may have the potential to alter an individual's health through various different pathways and mechanisms. This study aimed to explore the relationship between PA behaviours and the gut microbiome in older adults.

DESIGN

Cross-sectional study.

SETTINGS AND PARTICIPANTS

Participants (n=100; age 69.0 [3.0] years; 44% female) from the Mitchelstown Cohort Rescreen (MCR) Study (2015-2017).

METHODS

Participants provided measures of gut microbiome composition (profiled by sequencing 16S rRNA gene amplicons), and objective measures of PA behaviours (by a 7-day wear protocol using an activPAL3 Micro).

RESULTS

Standing time was positively correlated with the abundance of butyrate-producing and anti-inflammatory bacteria, including Ruminococcaceae, Lachnospiraceae and Bifidobacterium, MVPA was positively associated with the abundance of Lachnospiraceae bacteria, while sedentary time was associated with lower abundance of Ruminococcaceae and higher abundance of Streptococcus spp.

CONCLUSION

Physical activity behaviours appear to influence gut microbiota composition in older adults, with different PA behaviours having diverging effects on gut microbiota composition.

Associations of Sedentary Time with Energy Expenditure and Anthropometric Measures

PURPOSE

To investigate associations between accelerometer-determined sedentary time (ST) in prolonged (≥30 min) and nonprolonged (<30 min) bouts with physical activity energy expenditure (PAEE) from doubly labeled water. Additionally, associations between ST and body mass index (BMI) and waist circumference were examined.

METHODS

Data from 736 women and 655 men age 43 to 82 yr were analyzed. Participants wore the Actigraph GT3X for 7 d on two occasions approximately 6 months apart, and the average of the measurements was used. Physical activity energy expenditure was estimated by subtracting resting metabolic rate and the thermic effect of food from doubly labeled water estimates of total daily energy expenditure. Cross-sectional associations were analyzed using isotemporal substitution modeling.

RESULTS

Reallocation of prolonged ST to nonprolonged was not associated with increased PAEE and only significantly associated with lower BMI (β = -0.57 kg·m; 95% confidence interval, -0.94 to -0.20) and waist circumference (β = -1.61 cm; 95% confidence interval, -2.61 to -0.60) in men. Replacing either type of ST with light or moderate-to-vigorous physical activity was significantly associated with higher PAEE, and lower BMI and waist circumference in both women and men.

CONCLUSIONS

Limiting time spent sedentary as well as decreasing ST accumulated in prolonged bouts may have beneficial effects on BMI and waist circumference. Replacing any type of ST with activities of light or higher intensity may also have a substantial impact on PAEE.