A randomized controlled trial of continuous activity, short bouts, and a 10,000 step guideline in inactive adults
ABSTRACT Although several studies have examined the effect of accumulated bouts on health outcomes, the impact of recommending short bouts on activity-related behavior in health promotion efforts has received minimal investigation.
During this 5-week study in 2007-2008, 43 university employees (8 male, 35 female) in the Southeastern United States were randomly assigned to a group recommended to achieve (a) 10,000 steps (10K), (b) 30-minutes (30 min) of continuous physical activity, or (c) 30-minutes of activity in bouts of at least 10 minutes (bouts).
Repeated measures ANOVA revealed that the 10K group showed the largest increase in step counts whereas the bouts group showed the smallest change over the intervention period, p=0.01. Condition differences were most pronounced on days in which participants met their activity recommendation. Accelerometer results revealed that the 10K (d=1.1) and 30 min groups (d=0.89) showed large increases in minutes of moderate to vigorous activity (MVPA), whereas the bouts group showed minimal change (d=0.11). Although activity recommendations did not differentially affect self-efficacy, participants from all conditions showed decreased self-efficacy across the intervention (p=0.02), highlighting the need to develop strategies to increase self-efficacy in activity promotion efforts.
Full-textDOI: · Available from: Matthew T Mahar, May 29, 2015
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ABSTRACT: Objectives The objective of this study was to investigate changes in use of time when undertaking a structured exercise program. Design This study used a randomised, multi-arm, controlled trial design. Methods A total of 129 insufficiently active adults aged 18-60 years were recruited and randomly allocated to one of three groups, a Moderate or Extensive six-week exercise group (150 and 300 additional minutes of exercise per week, respectively) or a Control group. Prescribed exercise was accumulated through both group and individual sessions. Use of time was measured at baseline and end-program using the Multimedia Activity Recall for Children and Adults, a computerised 24-hour recall instrument. Daily minutes of activity in activity domains and energy expenditure zones were determined. Results Relative to changes in the control group, daily time spent in the Physical Activity [F (2, 108) = 20.21, p < 0.001] and Active Transport [F (2, 108) = 3.71, p = 0.03] time use domains significantly increased in the intervention groups by 21-45 minutes/day. Comparatively, the intervention groups spent significantly less time watching television [F (2, 108) = 5.02, p = 0.008; -50-52 min/day], relative to Controls. Additionally, time spent in the moderate to vigorous energy expenditure zone had significantly increased in the intervention groups by end-program [F (2, 108) = 6.35, p = 0.002; 48-50 min/day], relative to Controls. Conclusion This study is the first to comprehensively map changes in time use across an exercise program. The results suggest that exercise interventions should be mindful not only of compliance but of “isotemporal displacement” of behaviours.02/2014; DOI:10.1016/j.jsams.2014.01.004
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ABSTRACT: Objective Few postpartum ethnic minority women perform leisure-time moderate-to-vigorous physical activity (MVPA). The study tested the effectiveness of a 12-month tailored intervention to increase MVPA in women with infants 2–12 months old. Methods From 2008–2011, women (n = 311) with infants (average age = 5.7 months) from Honolulu, Hawaii were randomly assigned to receive tailored telephone calls and access to a mom-centric website (n = 154) or access to a standard PA website (n = 157). MVPA was measured at baseline, 6, and 12 months using self-report and acclerometers. Results Controlling for covariates, the tailored condition significantly increased self-reported MVPA from an average of 44 to 246 minutes/week compared with 46 to 156 minutes/week for the standard condition (p = 0.027). Mothers with ≥ 2 children had significantly greater increases in MVPA in response to the tailored intervention than those with one child (p = 0.016). Accelerometer-measured MVPA significantly increased over time (p = 0.0001), with no condition differences. There was evidence of reactivity to initially wearing accelerometers; the tailored intervention significantly increased MVPA among women with low baseline accelerometer MVPA minutes, but not among those with high minutes (pinteraction = 0.053). Conclusion A tailored intervention effectively increased MVPA over 12 months in multiethnic women with infants, particularly those with more than one child.Preventive Medicine 10/2014; 69. DOI:10.1016/j.ypmed.2014.09.019 · 2.93 Impact Factor
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ABSTRACT: Synopsis The increases in preventable chronic diseases and the rising costs of health care are unsustainable. The US Army Surgeon General's vision to transition from a health care system to a system of health requires the identification of key health enablers to facilitate the adoption of healthy behaviors. In support of this vision, the US Army Telemedicine and Advanced Technology Research Center hosted a workshop in April 2013 titled "Incentives to Create and Sustain Change for Health." Members of government and academia participated to identify key health enablers that could ultimately be leveraged by technology. The key health enablers discussed included (1) public health messaging, (2) changing health habits and the environmental influence on health, (3) goal setting and tracking, (4) the role of incentives in behavior-change intervention, and (5) the role of peer and social networks on change. This report summarizes leading evidence and the group consensus on evidence-based practices with respect to the key enablers in creating healthy behavior change. J Orthop Sports Phys Ther 2014;44(5):378-387. doi:10.2519/jospt.2014.0301.05/2014; 44(5):378-387. DOI:10.2519/jospt.2014.0301