Sedentary time was measured objectively using accelerometers. PI3K inhibitor There are also limitations within this study. The observational nature of the analysis means causality cannot be inferred and there is a possibility of residual confounding by other factors, for example dietary intake while sedentary. The analysis was performed separately by sex to allow for differences in the sedentary behaviours as a result of the intervention. There was a suggestion of a possible sex-by-sedentary time interaction for CRP with women exhibiting a greater increase in CRP per unit increase in sedentary time.
However, the large discrepancy in sample size between males and females makes meaningful comparisons between sexes difficult. PKC signaling Although accelerometers offer increased accuracy compared to self-report, they have a number of limitations for the measurement of sedentary time. Whilst the thresholds used to define MVPA measured with the Actigraph accelerometer in adults are well defined, a range of thresholds have been used to define sedentary time ,  and . In addition, the criteria used in data reduction procedures to discard continuous periods of zero values, generally interpreted as time when the accelerometer has been
removed, commonly range between 20 and 60 min. Since sedentary time is defined as <100 cpm, and estimates therefore include zero as a ‘real’ value, these decisions may impact upon the measured volume of sedentary time. Such methodological differences limit the potential for comparisons across studies. The thresholds for sedentary time and handling of zero values used in the current study were selected to allow comparison with the AusDiab data . A further limitation of waist-worn accelerometers in the measurement of sedentary time is their inability to differentiate between postures, and potential for misclassifying standing time as sedentary, since sedentary behaviour is defined as “any waking behaviour characterised by an energy
expenditure of less than or equal to 1.5 C1GALT1 metabolic equivalents while in a sitting or reclining posture” . To quantify the association between sedentary time and health outcomes precisely, more accurate measurement of sedentary time is required. The inflammatory profiles of participants in the present study were indicative of low-grade inflammation . Women had heightened inflammation, as indicated by elevated CRP, sICAM-1 and IL-6 compared to men. This is in agreement with previous studies who have also observed associations between sedentary time and adverse health outcomes in women only  and . Previous studies have suggested that the physical activity patterns of men, who tend to do more MVPA than women, may offer protection against the detrimental health effects of sedentary time .