Biomedical subjects

John R Sirard

Publications and source records attributed to John R Sirard.

8 recordsLinked to original sources

PubMed2006

Sport participation and physical activity in adolescent females across a four-year period.

PURPOSE: To determine the odds of engaging in future moderate-to-vigorous physical activity (MVPA) and vigorous physical activity (VPA) in adolescent female sport participants. A secondary purpose was to compare activity levels of three groups of girls, those who played sports at three time points, those who dropped out, and those who did not participate in sports. METHODS: Data were collected at three time points, eighth, ninth, and 12th grades, in 429 adolescent girls across the state of South Carolina. Demographic, sport participation and physical activity (PA) data were collected using surveys. Odds ratios were calculated to determine the association between sport participation and future PA behavior. PA was also compared for three sport participation groups (nonparticipants, dropouts, or three-year participants) using analysis of variance. RESULTS: For MVPA, ninth grade participants were more likely to be active in 12th grade (OR = 1.74 [1.13, 2.67]), and eighth and ninth grade participants more likely to be active in 12th grade than nonparticipants (OR = 1.54 [confidence interval 1.01, 2.35]). For VPA, sport participants had higher odds of being active at all future time points. Three-year participants were significantly more vigorously active than nonparticipants and dropouts at all three time points (p < .01). CONCLUSIONS: Adolescent girls who participate in sports in eighth, ninth, and 12th grades are more likely to be vigorously active in 12th grade. These findings are novel in providing evidence that sport participation contributes to overall vigorous physical activity during late adolescence, when overall physical activity is known to decline precipitously.

Adolescent↗

PubMed2006

Motivational factors associated with sports program participation in middle school students.

PURPOSE: The purposes of this study were 1) to identify gender-specific motivational factors associated with sports program participation and attrition in middle school students and 2) to examine the relationships among sports program participation, physical activity, and sedentary behavior in this age group. METHODS: Seventh and eighth grade students (N = 1692) completed a questionnaire to measure sports program participation and factors that may motivate continued participation in or attrition from sports. The psychometric properties of the participation and attrition scales were tested using gender-separate exploratory factor analysis. Analysis of variance (participation status*gender) was used to identify differences in motivational factor scores and physical activity variables. RESULTS: Eighty percent of the students were recent participants (within the past year), 10% were former participants, and 10% had never participated. For boys, the participation factors were labeled (in order) competition, social benefits, and fitness. For girls, factor structures were slightly different than the boys, which loaded as; social + skill benefits, competition, and fitness. For both genders, lack of interest, coaching problems, and time barriers were identified as attrition factors. Recent sport participants reported more time in vigorous (p < .01), stretching (p = .03), and strengthening activities (p < .01) and less time watching television (p < .01). CONCLUSIONS: Gender-specific motivational factors exist for middle school youth; boys are more attracted to the competitive aspects of sports whereas girls are more motivated by the social opportunities that sports provide. Boys and girls who participate in sports are more physically active, so it is important to develop programs that children want to participate in and maximize retention.

Adolescent↗

PubMed2006

Longitudinal and secular trends in physical activity and sedentary behavior during adolescence.

OBJECTIVE: There is little epidemiologic research on longitudinal and secular trends in weight-related health behaviors throughout the stages of adolescence. In particular, few data are available to assess secular trends in various sedentary behaviors. The objective of this research was to investigate longitudinal and secular trends in physical activity and sedentary behavior in a large, diverse cohort of adolescents. METHODS: Project EAT-II is a 5-year longitudinal study (N = 2516) that includes 2 cohorts that allow for the observation of longitudinal changes from early to midadolescence (junior high to high school; n = 806; mean baseline age: 12.8 +/- 0.8 years) and mid- to late adolescence (high school to post-high school; n = 1710; mean baseline age: 15.8 +/- 0.8 years). EAT-II also examined secular trends in health behavior from 1999 to 2004 in midadolescence. The main outcome measures of the mixed-model regression analyses used in this research were self-reported weekly hours of moderate to vigorous physical activity, television/video viewing, and leisure-time computer use. RESULTS: Our findings indicate substantial longitudinal changes in moderate to vigorous physical activity, particularly among girls (decreasing 5.9-4.9 hours/week from early to midadolescence and 5.1-3.5 hours/week from mid- to late adolescence), and leisure-time computer use, particularly among boys (increasing 11.4-15.2 hours/week from early to midadolescence and 10.4-14.2 hours/week from mid- to late adolescence). Secular trends further indicate dramatic increases in midadolescent computer use from 1999 to 2004; girls increased from 8.8 to 11.1 hours/week, and boys increased from 10.4 to 15.2 hours/week. CONCLUSIONS: These adolescents experienced unfavorable shifts in activity patterns, such as longitudinal decreases in moderate to vigorous physical activity, coupled with longitudinal and secular increases in leisure-time computer use. Developing effective health promotion strategies that address a wide array of changing behavioral patterns will be important in promoting long-term health and active lifestyles among adolescents and young adults.

Adolescent↗

PubMed2005

Preventing childhood obesity: a solution-oriented research paradigm.

Past research has identified social and environmental causes and correlates of behaviors thought to be associated with obesity and weight gain among children and adolescents. Much less research has documented the efficacy of interventions designed to manipulate those presumed causes and correlates. These latter efforts have been inhibited by the predominant biomedical and social science problem-oriented research paradigm, emphasizing reductionist approaches to understanding etiologic mechanisms of diseases and risk factors. The implications of this problem-oriented approach are responsible for leaving many of the most important applied research questions unanswered, and for slowing efforts to prevent obesity and improve individual and population health. An alternative, and complementary, solution-oriented research paradigm is proposed, emphasizing experimental research to identify the causes of improved health. This subtle conceptual shift has significant implications for phrasing research questions, generating hypotheses, designing research studies, and making research results more relevant to policy and practice. The solution-oriented research paradigm encourages research with more immediate relevance to human health and a shortened cycle of discovery from the laboratory to the patient and population. Finally, a "litmus test" for evaluating research studies is proposed, to maximize the efficiency of the research enterprise and contributions to the promotion of health and the prevention and treatment of disease. A research study should only be performed if (1) you know what you will conclude from each possible result (whether positive, negative, or null); and (2) the result may change how you would intervene to address a clinical, policy, or public health problem.

Adolescent↗

PubMed2005

A preliminary test of a student-centered intervention on increasing physical activity in underserved adolescents.

BACKGROUND: Previous studies have shown that choice and self-initiated behavior change are important for increasing intrinsic motivation and physical activity (PA), however, little of this research has focused on underserved adolescents. PURPOSE: This study examined the effects of a 4-week student-centered intervention on increasing PA in underserved adolescents. METHODS: Twenty-eight students in the intervention school were matched (on race, percentage on free or reduced-price lunch program, gender, and age) with 20 students from another school who served as the comparison group (30 girls, 18 boys; ages 10-12 years; 83% African American; 83% on free or reduced-price lunch). The student-centered intervention was consistent with self-determination (motivation) theory and social cognitive theory in that it emphasized increasing intrinsic motivation and behavioral skills for PA. Intervention adolescents took ownership in selecting a variety of PA activities in which to participate, and they generated coping strategies for making effective PA behavior changes. RESULTS: Intervention participants showed greater increases in accelerometer estimates of time spent in moderate PA, moderate-to-vigorous PA, and vigorous PA from baseline to Week 4 of the intervention than the comparison group. Intervention participants also showed greater increases in PA motivation and positive self-concept for PA than comparison adolescents. CONCLUSIONS: This study provides preliminary evidence that increasing adolescent involvement and choice of activities may be important in developing future PA interventions for underserved adolescents.

Adolescent↗

PubMed2005

Physical activity and active commuting to elementary school.

PURPOSE: This study was conducted to determine if fifth-grade students who walked or bicycled to school on a regular basis were more physically active than those that did not. METHODS: The sample consists of 219 fifth-grade students (10.3 +/- 0.6 yr, 44% male, 58% minority) from eight randomly selected urban and suburban elementary schools. Students wore an Acti-Graph physical activity monitor during the same week that they completed a daily survey to report their mode of transportation to and from school. Students were categorized on the number of reported active commuting trips, to and from school, per week (regular;>or=5 (N=11), irregular; 1-4 (N=25), nonactive; 0 (N=183)). RESULTS: Compared with both other groups, regular active commuters accumulated 3% more minutes of moderate-to-vigorous physical activity (MVPA; P=0.04) during weekdays. This weekday difference was because of regular active commuters accumulating 8.5% more minutes of MVPA both before and after school (P <or= 0.01). No difference in physical activity was seen among groups during school or in the evening. Based on the mean number of minutes the students wore their monitors on weekdays (800 min.d), the 3% difference translates into approximately 24 additional minutes of MVPA per day for the regular active commuters. CONCLUSION: Walking to school was associated with approximately 24 additional minutes of MVPA per day in fifth-grade students. Additional observational and experimental research in larger, more diverse samples is needed to further clarify the effects of active commuting to school on total daily physical activity and other health outcomes.

Bicycling↗

PubMed2005

Prevalence of active commuting at urban and suburban elementary schools in Columbia, SC.

We directly observed the prevalence of walking and bicycling (active commuting) to 8 randomly selected urban and suburban elementary schools. When school was used as the unit of analysis, only 5.0% of the students actively commuted to or from school across all observed trips. Active commuting was not affected (P >/=; 18) by school urbanization level, school socioeconomic status, time of day, day of week, weather conditions, or temperature. These results indicate a need for school- and community-based interventions.

Bicycling↗

PubMed2004

Influences of preschool policies and practices on children's physical activity.

The objective of this study was to determine if moderate to vigorous physical activity (MVPA) of 3-5 year old preschool children varied with differences in policies/practices, and overall quality of preschools. A total of 266 children (47% males, 60% African American) from 9 preschools were observed for 1 hour on 3 different days. PA of children was observed twice per minute and scored as 1-5, with 1 for stationary/motionless and 5 for fast movement. Summary MVPA was calculated over the 3 days as percent of times observed at levels of 4 or 5, and percent of time at levels 1 or 2 as sedentary activity. A structured interview about PA policies was conducted with an administrator at each preschool and overall quality of the preschool was assessed using Early Childhood Environment Rating Scale-Revised Edition (ECERS-R). Preschools were divided into groups according to whether a specific policy/practice that would be logically hypothesized to promote PA was in place at the school. MVPA differences between groups of children was assessed using mixed ANOVA controlling for preschool. When preschools offered more field trips, and more college educated teachers, the children participated in more MVPA. Children who attended preschools with lower quality spent more time in sedentary activity. In conclusion, children in preschools which may have more resources and better quality appear to show both more sedentary behavior and more MVPA.

Black or African American↗