Alicia Ann Thorp, Bronwyn A. Kingwell, Coralie English, Louise Hammond, Parneet Sethi, Neville Owen and David W. Dunstan
To determine whether alternating bouts of sitting and standing at work influences daily workplace energy expenditure (EE).
Twenty-three overweight/obese office workers (mean ± SD; age: 48.2 ± 7.9 y, body mass index: 29.6 ± 4.0 kg/m2) undertook two 5-day experimental conditions in an equal, randomized order. Participants wore a “metabolic armband” (SenseWear Armband Mini) to estimate daily workplace EE (KJ/8 h) while working (1) in a seated work posture (SIT condition) or (2) alternating between a standing and seated work posture every 30 minutes using a sit-stand workstation (STAND-SIT condition). To assess the validity of the metabolic armband, a criterion measure of acute EE (KJ/min; indirect calorimetry) was performed on day 4 of each condition.
Standing to work acutely increased EE by 0.7 [95% CI 0.3–1.0] KJ/min (13%), relative to sitting (P = .002). Compared with indirect calorimetry, the metabolic armband provided a valid estimate of EE while standing to work (mean bias: 0.1 [–0.3 to 0.4] KJ/min) but modestly overestimated EE while sitting (P = .005). Daily workplace EE was greatest during the STAND-SIT condition (mean condition difference [95% CI]: 76 [8–144] KJ/8-h workday, P = .03).
Intermittent standing at work can modestly increase daily workplace EE compared with seated work in overweight/obese office workers.
Bronwyn Kay Clark, Takemi Sugiyama, Genevieve N. Healy, Jo Salmon, David W. Dunstan, Jonathan E. Shaw, Paul Z. Zimmet and Neville Owen
Sedentary behaviors, particularly television viewing (TV) time, are associated with adverse health outcomes in adults, independent of physical activity levels. These associations are stronger and more consistent for women than for men.
Multivariate regression models examined the sociodemographic correlates of 2 categories of TV time (≥2 hours/day and ≥4 hours/day); in a large, population-based sample of Australian adults (4950 men, 6001 women; mean age 48.1 years, range 25–91) who participated in the 1999/2000 Australian Diabetes, Obesity, and Lifestyle (AusDiab) study.
Some 46% of men and 40% of women watched ≥ 2 hours TV/day; 9% and 6% respectively watched ≥ 4 hours/day. For both men and women, ≥2 hours TV/day was associated with less than tertiary education, living outside of state capital cities, and having no paid employment. For women, mid and older age (45−64 and 65+) were also significant correlates of ≥2 hours TV/day. Similar patterns of association were observed in those viewing ≥4 hours/day.
Prolonged TV time is associated with indices of social disadvantage and older age. These findings can inform the understanding of potential contextual influences and guide preventive initiatives.