IPLAY: The Intervention of PhysicaL Activity in Youth (IPLAY) Study is a five year project funded by NIH to examine the effects of an environmental and curricular intervention on levels of physical activity in children. The environmental modification includes the construction of colorful, multi-use, activity-promoting Learning Landscapes playgrounds (see photo below). The curriculum involves SPARK Active Recreation at recess and Balance First during PE. Our responsibility is to objectively monitor physical activity levels in a subsample of first, third and fifth grade students using accelerometers. We found that during recess, boys were more active than girls. Also, boys with renovated playgrounds participate in more MVPA during recess than boys without renovated playgrounds, while girls do not. During recess there were no significant differences between normal weight and overweight children. See Figure 1.

Figure 1. Average percent of moderate-vigorous physical activity (MVPA) during recess. Values inside bars represent minutes of MVPA during recess. LL= Learning Landscapes (renovated playgrounds), non-LL= Non-Learning Landscapes (non-renovated playgrounds), NW= Normal weight, OW/OB= Overweight/Obese.

Accelerometer Calibration Studies: We are conducting calibration studies on various accelerometers in 6-11 year old children. We collect metabolic data using the Oxycon Mobile portable metabolic cart, and accelerometry data using the Actical, Actigraph and GeneActiv monitors placed on the wrist. Children participate in a variety of activities including coloring, walking, jogging, playing foursquare, playing Wii®, and various activities on a local playground. The goal of the calibration studies is to determine cutpoints to distinguish between sedentary, light, moderate and vigorous activity. Here we have examined the relationship between metabolic equivalents (METs) and Actical accelerometer counts using linear regression. Cutpoints have been established for sedentary (≤1.5 METs), light (1.5-3 METs), moderate (3-6 METs) and vigorous (≥ 6 METs) activity (see Figure 2).

Figure 2. Cutpoints for accelerometer count and METs.

Active Classroom Project: We have just set up the first classroom at CSU to promote a less sedentary learning environment. The classroom has been equipped with 10 fit-ball chairs and a back-row of standing height desks. Research is on-going about professor and student acceptance of this new learning environment.

Stairwell project: We are starting a project looking at whether the positioning of a stairwell or elevator in a building can affect stair usage. Previous research has shown that making stairways more aesthetically pleasing can lead to increased stair use. The next question is whether the location of stairways in a building will have similar effects.

Calibrate and validate a new footwear based physical activity monitor. We have a just completed a National Institutes of Health (NIH) grant to develop a new physical activity monitor that uses insole pressure and accelerometry to quantify posture allocation, types of activity and energy expenditure. Our results show that this device is more accurate than other commercially available devices (see figure 4).

Figure 4: Mean (SE) measured and estimated energy expenditure using each device.