Pedometer steps-per-minute, moderate intensity, and individual differences in 12- to 14-year-old youth.

BACKGROUND: Researchers have noted both the utility and limitations of using pedometers to measure physical activity (PA). While these unobtrusive devices are widely accepted for their ability to measure accumulated PA, they have been criticized for their inability to measure exercise intensity. However, recent steps-per-minute (SPM) research provides reasonably accurate measures of intensity allowing users to assess time spent at recommended PA levels. Therefore, the purpose of this study was to determine the SPM taken that are associated with moderate physical activity in 12- to 14-year-old youth. METHODS: Ninety-three participants (49 boys and 44 girls; ages 12 to 14) walked on a treadmill for 3 minutes at each of 4 different speeds while wearing a pedometer and a heart rate monitor. RESULTS: On average boys and girls reached their moderate activity intensity threshold at 122 SPM and 102 SPM, respectively. However, individual differences must be taken into account when determining appropriate SPM intensities for youth. CONCLUSIONS: The impact of individual differences underscores the need to address SPM for moderate intensity individually rather than with a single guideline for everyone at this age.

A prospective study of pedometer-determined physical activity and physical self-perceptions in children.

There have been limited prospective studies investigating physical activity and physical self-perceptions in children. In this investigation, mean steps/day did not significantly change from late elementary to junior high for either boys or girls; however; boys accumulated more steps both at baseline and follow-up. Physical self-perception measures were significantly related to changes in steps/day and accounted for 21% (15% adjusted) of the variance after controlling for demographic/biological variables, R2 change = .21, adjusted R2 change = .15, F (5,88) = 4.66, p < .001. Sport competence emerged as the most important predictor t (88) = -3.76, p < .001, and was inversely related to physical activity change. The lack of opportunities to participate in sport activities normally found at the onset of adolescence may help explain this unexpected result.

Effects of placement, attachment, and weight classification on pedometer accuracy.

BACKGROUND: The purpose was to determine if waist placement of the pedometer affected accuracy in normal, overweight, and obese children, when attaching the pedometer to the waistband or a belt. METHODS: Seventy-seven children (ages 10-12 years) wore 5 pedometers on the waistband of their pants and a belt at the following placements: navel (NV), anterior midline of the right thigh (AMT), right side (RS), posterior midline of the right thigh (PMT), and middle of the back (MB). Participants walked 100 steps on a treadmill at 80 m x min(-1). RESULTS: The RS, PMT, and MB sites on the waistband and the AMT and RS sites on the belt produced the least error. CONCLUSIONS: Of these sites, the RS placement is recommended because of the ease of reading the pedometer during activity. Using a belt did not significantly improve accuracy except for normal weight groups at the NV placement site.