Physical Activity in Girl Scout Junior Troop Meetings – Part 3

Over the course of the observation period, objective monitoring was conducted on seven occasions at each troop meeting site. At the beginning of each meeting, a research assistant used an adjustable elastic belt to place an ActiGraph GT1M accelerometer-based physical activity monitor (Shalimar, FL), on the right hip of each participating girl. Start time and identification number of each monitor was recorded. The monitor was worn for the duration of each girl’s attendance of the meeting. A 30-second epoch was employed to obtain an objective assessment of physical activity and sedentary behavior. At the end of the troop meeting, the research assistant removed all monitors and recorded the time.
Monitors were then taken back to the laboratory for data downloading and storage. Raw accelerometer counts were processed through a customized software program for determination of time spent in moderate-to-vigorous (≥ 4 METs), vigorous (≥ 7 METs), moderate (4-6.99 METs), light (1.5–3.99 METs), and sedentary (< 1.5 METs) physical activity levels. The age-specific count thresholds corresponding to these intensity levels were derived from the MET prediction equation developed by Freedson and co-workers (2005) and the appropriate count thresholds were divided by two to accommodate the 30-second epoch length. Invalid wearing time during the meeting period was assessed by counting the number of consecutive zero counts accumulated in strings of 10 min or longer. Accelerometer data for the entire meeting period was considered valid if wearing time was equal to or greater than 30 min. During each meeting, a research assistant continuously observed the troop environment and activities. The research assistant recorded the details of the meeting using a form called the SNAP Session Form (appendix A), which was patterned off SOPLAY (McKenzie et al., 2000). Session was defined as a period of time when 51% or more of girls were engaged in one activity. The SNAP Troop Observation Form (appendix B) was used to record the general structure, general content, knowledge content and leader behavior relevant to promotion of physical activity. The recommended guidelines for behavioral observation were used to develop the behavioral and environmental observation system and both forms (Herbert and Attridge, 1975). The behavioral and environmental observation system and forms were largely patterned off of previously validated methodology (McKenzie et al., 1992).
Every 60 seconds, a vibrating timing device (Time Now Inc., Model: Invisible Clock II, Larkspur, CA), alerted the research assistant to determine the presence or absence of leader behavior relevant to the promotion or discouragement of physical activity (verbal or physical) in the preceding 60 seconds. Verbal encouragement of physical activity such as ―keep going!‖ or ―Run!‖ would constitute verbal promotion of physical activity. Physical promotion of physical activity included leaders’ modeling or demonstrating a physical skill to be copied by the scouts, or participation in the games or physical activities performed by the girls. The portable timing device was used for the duration of the troop meeting. Careful training for use of all forms and observation techniques was provided for the two research assistants, and prior to actual data collection adequate inter-rater reliability (>90% agreement) was obtained.