Background: Effective physical activity interventions are needed for children because health behaviors track into adulthood, and risk factors for diseases begin early in life. No study has determined whether an intervention designed using a Community-Based Participatory Research approach can improve moderate to vigorous physical activity (MVPA) and the related psychosocial constructs in underserved children. This study determined whether improvements in MVPA and related psychosocial constructs (self-efficacy, knowledge, beliefs, attitudes, and skills) occurred following a Community-Based Participatory Research intervention in underserved, rural children. It was then determined if these constructs were mediators of MVPA. Methods: Two fifth-grade classes at a school (n = 19 and n = 20) were randomly assigned to an intervention or comparison group. The intervention group participated in a 4-week intervention designed to improve MVPA (wGT3X-BT accelerometer; ActiGraph, Pensacola, FL) and the related psychosocial constructs (written survey). Groups were assessed prior to and immediately following the intervention. Results: There were no differences at baseline between groups. MVPA (30.0 [4.4] min), knowledge, and skill scores were significantly higher in the intervention group compared with the comparison group at follow-up (P < .05). Knowledge and skills were mediating variables of MVPA. Conclusions: Priority should be placed on research that determines the sustained impact of similar Community-Based Participatory Research interventions.
Kara C. Hamilton, Mark T. Richardson, Shanda McGraw, Teirdre Owens and John C. Higginbotham
Steven R. McAnulty, Lisa S. McAnulty, Jason D. Morrow, David C. Nieman, John T. Owens and Cristin M. Carper
This study compared effects of carbohydrate (CHO) and rest on oxidative stress during exercise. Cyclists (N = 12) completed 4 randomized trials at 64% Wattsmax under 2 conditions (continuous cycling for 2 h [C] and cycling with 3-min rest every 10 min for 2.6 h [R]). Subjects cycled under each condition while receiving 6% CHO and placebo (PLA). CHO and PLA were given pre exercise (12 mL/kg) and during exercise (4 mL·kg−1·15 min−1). Blood was collected pre exercise, post exercise, and 1 h post exercise and assayed for F2-isoprostanes, hydroperoxides (LH), nitrite, antioxidant capacity, glucose, insulin, cortisol, and epinephrine. F2-isoprostanes and LH were lower in CHO. Glucose, cortisol, and epinephrine exhibited significant effects, with post exercise levels of glucose higher and cortisol and epinephrine lower in CHO during the R condition. This pattern was identical in the C condition (21). Oxidative stress during cycling was unaffected by use of short rest intervals but was diminished by CHO.
Bonnie G. Berger, Robert W. Motl, Brian D. Butki, David T. Martin, John G. Wilkinson and David R. Owen
This study examined changes in mood and performance in response to high-intensity, short-duration overtraining and a subsequent taper. Pursuit cyclists (N = 8) at the United States Olympic Training Center completed the POMS and simulated 4-km pursuit performance tests throughout a six-week period. The six-week period included a baseline week, three weeks of overtraining that consisted primarily of high-intensity interval training, and a two-week taper. Total Mood Disturbance (TMD) scores displayed a quadratic polynomial effect across the three weeks of overtraining (p < .01), with the highest TMD scores occurring in the second week. Average TMD scores were lower during the taper than at baseline (p < .02) and lower at taper than overtraining (p < .0005). Cycling performance (pursuit time and average power output) improved during the three weeks of overtraining; additional improvements were observed during the taper. There were no significant correlations between TMD and performance. However, pursuit time, average power output, and mood disturbance scores were at optimal levels throughout the taper period. These findings suggest that high-intensity, short-duration overtraining may not result in an overtraining syndrome in 4-km pursuit cyclists.