Effects of a curriculum and inservice program on the quantity and quality of elementary physical education classes.

The primary responsibility for engaging children in opportunities to be physically active and learn physical skills rests with school physical education. This study evaluated the effects of a combined health-related curriculum and inservice program on the quantity and quality of elementary school physical education lessons. Seven schools (N = 28 fourth-grade classes) in one district were randomly assigned to one of three conditions: 10 classes were taught in their usual manner by classroom teachers (Control [CO]); 10 classes were taught by trained classroom teachers (TT) who received inservice training and follow-up consultations; and 8 classes were taught by physical education specialists (PES) hired by the research project. Student activity level, curriculum context, and teacher behavior were directly observed and coded during a sample of 112 lessons over an 8-month period. Results indicated significant differences in both the frequency and mean length of classes (PES, 26.7 min; TT, 23.4 min; CO, 18.9 min). Additionally, the curriculum and inservice program equipped trained classroom teachers to provide significantly better classes than were provided by controls in terms of student activity engagement, lesson context, and active instructional behavior, though their classes did not match the quality of those taught by the physical education specialists. This study is unique in its use of direct observation of lessons to assess a curriculum and inservice intervention.

The development of self-administered physical activity surveys for 4th grade students.

This study evaluates the test-retest reliability and validity of self-report measures of physical activity that can be self-administered in classroom settings to 4th grade students. Four different self-report formats were tested on 66 students. To assess test-retest reliabilities, self-report measures were administered on two occasions, separated by a 3-day interval between Time 1 (Friday) and Time 2 (Monday). One-way model intraclass reliabilities ranged from .51 to .74. Three days of monitoring with the Caltrac accelerometer were used as the validity criterion. Only one of the three weekly recalls, the Weekly Activity Checklist, was supported by significant validity correlations at both Time 1 (r = .34, p < .01) and Time 2 (r = .26, p < .05). The 1-day recall, Yesterday Activity Checklist, correlated significantly (r = .33, p < .01) with the previous day's Caltrac monitor score. Although two of the physical activity recall formats were found to be superior to two others, these data highlight the limitations of children's self-reports. Two self-report formats were found to have modest levels of reliability and validity with 4th grade children when administered in a classroom setting.

Seven-day recall and other physical activity self-reports in children and adolescents.

There is need to develop low cost, practical, and accurate measures of physical activity in children and adolescents, and self-report is a promising methodology for children that is applicable for large studies. The purpose of the present study was to assess the reliability and validity of several self-reports of physical activity. Subjects were 36 fifth-, 36 eighth-, and 30 eleventh-grade male and female students. The test-retest reliabilities were r = 0.77 for the 7-d recall interview, r = 0.81 for the Godin-Shephard self-administered survey, and r = 0.93 for a simple activity rating. For the former two measures, reliability improved with age but was significant at all ages, and for the last measure there were no age effects. Memory skills and obesity status were not related to the reliability of recall, but males were more reliable reporters than females. Validity of the 7-d recall was determined by comparing heart rate monitoring records with recalls of very hard activities on the same day. A correlation of 0.53 (P < 0.001) for the total group supported the validity of the reports. Validity improved with age, but validity coefficients were significant in all age groups. These data indicate that physical activity recalls of children as young as the fifth grade are of adequate reliability and validity to use in research on physical activity in children.

Reliability of interviewers using the Seven-Day Physical Activity Recall.

The Seven-Day Physical Activity Recall interview is commonly used in epidemiologic research, but the methods of training and certifying interviewers have not been studied or standardized. The purpose of this study was to examine the reliability of the Seven-Day Physical Activity Recall interviews after a structured training program. Twenty-one volunteer interviewers participated in a five-session group training program that targeted standardized interview techniques and scoring procedures. Interviewers scored eight videotaped interviews on two occasions to assess scoring skills. Across all videotapes and interviewers, the test-retest reliability was .99. Two interviewers independently interviewed the same person on the same day, and the reliability of kilocalorie expenditure across interviewers was .86. It was concluded that naive individuals can be taught to reliably conduct and score the Seven-Day Physical Activity Recall interview in a brief training program.

The Caltrac accelerometer as a physical activity monitor for school-age children.

The performance of the Caltrac accelerometer was studied in elementary school-age children under field and laboratory conditions. In Study 1, 35 children (20 boys, 15 girls, mean age = 10.8 yr) wore the accelerometer and a heart rate (HR) monitor for 2 d. Caltrac activity counts per hour were compared to the mean "activity HR", which was calculated by subtracting the mean of the five lowest HRs of the day from each recorded HR. Pearson r's between accelerometer and activity HR were 0.54 (P less than 0.001) on day 1 and 0.42 (P less than 0.02) on day 2. Inter-instrument reliability in the field was r = 0.96. Both accelerometer and HR data were significantly correlated with physical activity recalls of the same day. In Study 2, 15 children walked/ran for 10 min at 3, 4, and 5 mph on a horizontal treadmill while wearing two accelerometers. Oxygen uptake was directly measured each minute. Reliability of the Caltracs in the laboratory was 0.89. Activity count correlated r = 0.82 (SEE = 23%) with net calorie cost per kg of body weight. Net caloric expenditure per kg of weight was 0.101 kcal.kg-1.d-1 per Caltrac activity count. These data support the use of the Caltrac accelerometer as a physical activity measure for school-age children, and the objective data tended to corroborate the children's short-term activity recalls.