Volume and Intensity of Stepping Activity and Cardiometabolic Risk Factors in a Multi-ethnic Asian Population.

The health benefits of objectively measured physical activity volume versus intensity have rarely been studied, particularly in non-western populations. The aim of this study was to investigate the association between cardiometabolic risk factors and stepping activity including; volume (step count), intensity (cadence) or inactivity (zero-steps/minute/day), in a multi-ethnic Asian population. Participants clinical data was collected at baseline and their physical activity was monitored for seven days, using an accelerometer (Actigraph GT3X+) in 2016. Tertiles (low, moderate, high) of the mean daily step count, peak one-minute, 30-min, 60-min cadences and time/day spent at zero-steps/minute were calculated. Adjusted linear regressions explored the association between stepping activity tertiles and cardiometabolic risk factors. A total of 635 participants (41% male, 67% Chinese, mean age 48.4 years) were included in the analyses. The mean daily step count was 7605 (median daily step count 7310) and 7.8 h of awake time per day were spent inactive (zero-steps/minute). A greater number of associations were found for step intensity than volume. Higher step intensity was associated with reduced body mass index (BMI), waist circumference, blood pressures and higher high-density lipoprotein (HDL). Future health promotion initiatives should consider the greater role of step intensity to reduce cardiometabolic risk.

Stepping volume and intensity patterns in a multi-ethnic urban Asian population.

BACKGROUND: Accelerometer measured physical activity (PA) studies particularly in non-western populations are lacking. Therefore, this study investigated stepping activity in a multi-ethnic urban Asian population. METHODS: Adult participants from the Singapore Health Study 2 consented to accelerometer activity monitoring for 7-consecutive days. Mean daily step count, peak stepping intensity (i.e. cadence) over 1-min, 30-min and 60-min and time spent in each cadence band: 0 (non-movement), 1-19, 20-39, 40-59, 60-79, 80-99 and ≥ 100 steps/minute (moderate to vigorous PA) were calculated. RESULTS: A total of 713 participants (42% male, mean age 47.8 years) were included. Overall, the mean daily step count was 7549. Mean daily step count was significantly lower in Indians (7083 adjusted p = 0.02) but not Malays 7140 (adjusted p = 0.052) compared to Chinese (7745 steps). The proportion of Malays, Indians, and Chinese achieving < 5000 daily steps was 26%, 23% and 14%, respectively (p < 0.01). Regardless of ethnicity, approximately half of the recorded time was spent undertaking 0-steps/minute (7.9 h). CONCLUSIONS: Greater promotion of brisk walking is required in light of the low step volume and pace observed in this multi-ethnic Asian population. Ethnic differences in stepping activity were also identified which indicates a need for targeted ethnic specific health promotion interventions.

Cross-validation of a non-exercise measure for cardiorespiratory fitness in Singaporean adults.

INTRODUCTION: Cardiorespiratory fitness (CRF) is an independent predictor of voluminous health outcomes and can be measured using non-exercise fitness assessment (NEFA) equations. However, the accuracy of such equations in Asian populations is unknown. The objective of this study was to cross-validate the NEFA equation, developed by Jurca et al in 2005, in the adult Singaporean population. METHODS: A total of 100 participants (57 men, 43 women; aged 18-65 years) were recruited, and their maximal oxygen consumption (VO2 max) was measured in the laboratory by indirect calorimetry. The participants also completed the NEFA questionnaire, which helps to predict VO2 max with the NEFA equation. The relationship between NEFA-predicted and laboratory-measured VO2 max values was analysed. RESULTS: Overall, our study demonstrated a high correlation between the NEFA-predicted and laboratory-measured VO2 max values (r = 0.83). The Pearson's correlation coefficient values for the men and women in the study were 0.61 and 0.77, respectively. To improve the accuracy of the predictive equation, we transformed the original equation developed by Jurca et al into new equations that would allow estimation of VO2 max with and without resting heart rate as a variable. CONCLUSION: The modified NEFA equations accurately estimated CRF and may be applied to the majority of adult Singaporeans. With this, health practitioners and researchers are now able to assess CRF levels at both the individual and population levels in either the primary care, fitness or research setting.

The use of point-of-decision prompts to increase stair climbing in Singapore.

Physical inactivity is a significant contributor to worldwide mortality and morbidity associated with non-communicable diseases. An excellent avenue to incorporate lifestyle physical activity into regular routine is to encourage the use of stairs during daily commutes. We evaluated the effectiveness of point-of-decision prompts (PODPs) in promoting the use of stairs instead of the escalators in a Singapore Mass Rapid Transit (MRT) station. We measured the number of stair climbers before the PODPs were put up, during the 4 weeks that they were in use, and 2 weeks after they were removed. Measurements at a no intervention control site were additionally taken. The use of stair-riser banners was associated with an increase in the number of people using the stairs by a factor of 1.49 (95% CI 1.34-1.64). After the banners were removed, the number of stair climbers at the experimental station dropped to slightly below baseline levels. The Singapore MRT serves a diverse multi-ethnic population with an average daily ridership of over 2 million and 88 stations island-wide. An increase of physical activity among these MRT commuters would have a large impact at the population level. Our findings can be translated into part of the national strategy to encourage an active lifestyle in Singaporeans.