Publications by authors named "D Dunstan"

This study examined acute effects of interrupting prolonged sitting with short activity breaks on postprandial glucose/insulin responses and estimations of insulin sensitivity in adults with type 1 diabetes (T1D). In a randomized crossover trial, eight adults (age = 46 ± 14 years [mean ± SD], body mass index [BMI] = 27.2 ± 3.

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Background: Allogeneic stem cell transplantation (allo-SCT) is an efficacious treatment for hematologic malignancies but can be complicated by cardiac dysfunction and exercise intolerance impacting quality of life and longevity. We conducted a randomized controlled trial testing whether a multicomponent activity intervention could attenuate reductions in cardiorespiratory fitness and exercise cardiac function (co-primary end points) in adults undergoing allo-SCT.

Methods: Sixty-two adults scheduled for allo-SCT were randomized to a 4-month activity program (n=30) or usual care (UC; n=32).

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Background: The online BeUpstanding™ program is an eight-week workplace-delivered intervention for desk-based workers to raise awareness of the benefits of sitting less and moving more and build a supportive culture for change. A workplace representative (the "champion") delivers the program, which includes a workshop where teams collectively choose their sit less/move more strategies. A toolkit provides the champion with a step-by-step guide and associated resources to support program uptake, delivery, and evaluation.

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Background: Wrist-worn data from commercially available devices has potential to characterize sedentary time for research and for clinical and public health applications. We propose a model that utilizes heart rate in addition to step count data to estimate the proportion of time spent being sedentary and the usual length of sedentary bouts.

Methods: We developed and trained two Hidden semi-Markov models, STEPHEN (STEP and Heart ENcoder) and STEPCODE (STEP enCODEr; a steps-only based model) using consumer-grade Fitbit device data from participants under free living conditions, and validated model performance using two external datasets.

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Introduction: Muscle activation during interruptions to prolonged sedentary time is a hypothesized mechanism underlying observed cardiometabolic benefits. We examined associations of quadriceps and hamstring muscle activity patterns with cardiometabolic risk markers and how these patterns varied between different sitting-interruption countermeasures.

Methods: Electromyographic (EMG) data (shorts) were gathered for 1 to 2 d from healthy adults in a free-living study ( n = 172, age 40.

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