This study compared the conventional track and a new one-handed track start in elite age group swimmers to determine if the new technique had biomechanical implications on dive performance. Five male and seven female GB national qualifiers participated (mean ± SD: age 16.7 ± 1.9 years, stretched stature 1.76 ± 0.8 m, body mass 67.4 ± 7.9 kg) and were assigned to a control group (n = 6) or an intervention group (n = 6) that learned the new one-handed dive technique. All swimmers underwent a 4-week intervention comprising 12 ± 3 thirty-minute training sessions. Video cameras synchronized with an audible signal and timing suite captured temporal and kinematic data. A portable force plate and load cell handrail mounted to a swim starting block collected force data over 3 trials of each technique. A MANCOVA identified Block Time (BT), Flight Time (FT), Peak Horizontal Force of the lower limbs (PHF) and Horizontal Velocity at Take-off (Vx) as covariates. During the 10-m swim trial, significant differences were found in Time to 10 m (TT10m), Total Time (TT), Peak Vertical Force (PVF), Flight Distance (FD), and Horizontal Velocity at Take-off (Vx) (p < .05). Results indicated that the conventional track start method was faster over 10 m, and therefore may be seen as a superior start after a short intervention. During training, swimmers and coaches should focus on the most statistically significant dive performance variables: peak horizontal force and velocity at take-off, block and flight time.
H. Galbraith, J. Scurr, C. Hencken, L. Wood and P. Graham-Smith
Marc Theeboom, Paul De Knop and Maureen R. Weiss
Recent research in educational psychology suggests that provision of a mastery motivational climate will maximize enjoyment, perceived competence, and intrinsic motivation in children (Ames, 1992a, 1992b, 1992c). Minimal research has been conducted to test this proposition in the physical domain. The purpose of this study was to examine the effectiveness of a performance versus mastery oriented teaching program on children’s enjoyment, perceived competence, intrinsic motivation, and motor skill development. Children (N = 119) 8 to 12 years of age were randomly assigned to one of the two programs for 3 weeks during an organized sports program. Results revealed that children in the mastery oriented group reported significantly higher levels of enjoyment and exhibited better motor skills than those in the performance oriented group. In-depth interviews further indicated that children in the mastery program were almost unanimous in reporting high levels of perceived competence and intrinsic motivation, while those from the traditional group showed less pronounced effects. These results provide empirical evidence that a mastery motivational climate can result in more positive experiences for young athletes as they learn new skills.
Victoria Catenacci, Christopher Barrett, Lorraine Odgen, Ray Browning, Christine Adele Schaefer, James Hill and Holly Wyatt
The America on the Move (AOM) Family Intervention Program has been shown to prevent excess weight gain in overweight children. Providing intervention materials via the internet would have the potential to reach more families but may increase sedentary behavior. The purpose was to evaluate whether delivering the AOM Family Intervention via the internet versus printed workbook would have a similar impact on sedentary behaviors in children.
131 children (age 8–12) were randomized to receive the AOM Family Intervention via the internet or workbook for 12 weeks. Changes in objectively measured sedentary time and moderate-to vigorous physical activity (MVPA) as well as self-reported screen time were compared between groups.
There were no significant differences between groups in screen time, sedentary time, or MVPA at the end of the 12 week intervention. Families receiving the intervention via the internet were more likely to remain in the study (98% vs. 82%, P = .016).
Using the internet to deliver the lifestyle intervention did not increase sedentary behavior in children. Attrition rates were lower when the program was delivered by internet versus via printed materials. These results provide support for using the internet to deliver healthy lifestyle programs for children.
Stig Eiberg, Henriette Hasselstrom, Vivian Grønfeldt, Karsten Froberg, Ashley Cooper and Lars Bo Andersen
The aim of this study was to investigate whether risk factors for cardiovascular disease cluster in 6- to 7-year-old children and whether low physical fitness is a predictor of risk factor clustering. The study included 369 boys (6.8 ± 0.4 years) and 327 girls (6.7 ± 0.4 years). VO2max was directly measured during a treadmill test. The ratio of total cholesterol to high-density cholesterol, triglyceride levels, the ratio of insulin to glucose, systolic blood pressure, and the sum of four skinfolds were selected as risk factors. A child was considered at risk for individual factors if he or she had values in the least favorable quartile. The number of children with more than three cardiovascular disease cluster risk factors was not significantly different from a binominal distribution. This lack of clustering could be a result of the fact that these young children have not yet developed insulin resistance. Children in the lowest quartile of fitness had an odds ratio of 2.1 (CI: 1.0–4.4) for having three or more risk factors compared with the most fit. This is interesting with regard to prevention because it indicates that an intervention involving increased physical activity might postpone or even prevent the development of risk factors.
Wagner Luiz Prado, Mara Cristina Lofrano-Prado, Lila Missae Oyama, Michelle Cardel, Priscyla Praxedes Gomes, Maria Laura S.S. Andrade, Camila R.M. Freitas, Prabhakaran Balagopal and James O. Hill
Little is known about how the intensity of aerobic training influences appetite-regulating hormones in obese adolescents. Our goal was to assess the effect of low and high intensity aerobic trainings on food intake and appetite-regulating hormones in obese adolescents. Forty three obese adolescents (age: 13–18y, BMI: 34.48 ± 3.94 kg/m2) were randomized into high intensity training (HIT; n = 20) or low intensity training (LIT; n = 23) groups for 12 weeks. All participants also received the same nutritional, psychological and clinical counseling. Pre- and postintervention energy intake (EI) and circulating levels of insulin, leptin, peptide YY3–36 (PYY3–36) and ghrelin were measured. Adolescents in the HIT showed a reduction in total EI and an increase in PYY3–36 (p < .05). Aerobic exercise training performed at ventilatory threshold 1 intensity, reduced EI and augmented PYY3–36 in obese adolescents, compared with LIT. The data suggest that HIT and LIT have differential effects in the regulation of appetite signals and subsequent EI in obese adolescents.
Kathleen Van Royen, Roosmarijn Verstraeten, Susana Andrade, Angélica Ochoa-Avilés, Silvana Donoso, Lea Maes and Patrick Kolsteren
Physical inactivity levels are increasingly prevalent among Ecuadorian adolescents. School-based interventions can be potentially effective in promoting physical activity but must be informed by cultural-specific factors.
Twelve focus groups were carried out with adolescents (n = 80) in rural and urban Ecuador to identify factors influencing physical activity. In addition, 4 focus group discussions with parents (n = 32) and 4 with school staff (n = 32) were conducted. Individual and environmental factors were questioned using the ‘Attitude, Social influences and Self-efficacy’ model and the socioecological model as theoretical frameworks.
Factors influencing physical activity varied between groups. In the rural area farming and norms for girls impeded leisure-time physical activity, whereas urban groups emphasized traffic and crime concerns. Groups from a low socioeconomic status more frequently mentioned a fear of injuries and financial constraints. Several factors were common for all groups including preferences for sedentary activities, poor knowledge, time constraints and laziness, as well as a lack of opportunities at home and school, unsupportive parental rules and lack of role models.
A conceptual framework including the identified factors emerged to inform the design of a cultural-sensitive school-based intervention to improve physical activity among Ecuadorian adolescents. Future interventions should be tailored to each setting.
Adam B. Lloyd, David R. Lubans, Ronald C. Plotnikoff and Philip J. Morgan
This study examined potential parenting-related mediators of children’s physical activity and dietary behavior change in the Healthy Dads, Healthy Kids (HDHK) community program.
A randomized controlled trial was conducted with 45 overweight/obese (mean [SD] age = 39.8 [5.4] years; BMI = 32.4 [3.8]) fathers and their children (n = 77; 58% boys; mean [SD] age = 7.7 [2.5] years). Families were randomized to either the HDHK program or wait-list control group. The program involved 7 sessions. Fathers and their children were assessed at baseline and at 14 weeks for physical activity (pedometery) and core food intake (Questionnaire). Fathers’ lifestyle-related parenting practices included; self-efficacy, beliefs, modeling, logistic support, rules, cophysical activity, shared mealtime frequency and intentions.
Significant intervention effects were found for cophysical activity and modeling physical activity. Cophysical activity mediated children’s physical activity in the intervention (‘mediated effect,’ AB = 653, 95% CI = 4–2050) and was responsible for 59.5% of the intervention effect. Fathers’ beliefs mediated children’s percent energy from core foods (AB = 1.51, 95% CI = 0.05–5.55) and accounted for 72.9% of the intervention effect.
Participation in the HDHK program positively impacted on fathers’ cophysical activity with their child and beliefs about healthy eating which mediated changes in children’s diet and physical activity behaviors.
Meghan Baruth, Sara Wilcox, Cheryl Der Ananian and Sue Heiney
Adjuvant treatment for breast cancer may result in long-lasting, adverse emotional and physical side effects, and reduce quality of life (QOL). This pilot study examined the effects of a home-based walking program on QOL and fatigue in early stage breast cancer survivors and whether changes in walking behavior were associated with changes in outcomes.
Participants (n = 32) were randomized to a 12-week home-based walking intervention plus brief telephone counseling (n = 20) or a wait-list control group (n = 12). Self-reported fatigue, QOL, and walking were assessed at baseline and 12-weeks. Results are presented as effect sizes.
Participants in the intervention had improvements in a majority of fatigue and QOL outcomes, whereas the control group had no change or worsened in many; effect sizes were generally in the small to medium range. Changes in fatigue/QOL outcomes were associated with changes in walking behavior, with effects generally in the small to medium range.
Home-based physical activity (walking) programs may be an appropriate avenue for alleviating the adverse side effects that often accompany adjuvant treatment for breast cancer. These programs have potential for widespread dissemination, which may have considerable impact on the quality of life of women recently completing breast cancer treatment.
Kent A. Lorenz, Hans van der Mars, Pamela Hodges Kulinna, Barbara E. Ainsworth and Melbourne F. Hovell
Increasing access and opportunity for physical activity (PA) in schools are effective; however, not everyone experiences the same effects. Prompting and reinforcement may encourage more frequent participation in recreational PA during the school day. The purpose of this study was to investigate a lunchtime PA intervention on whole school PA participation and whether behavioral support enhanced these effects.
A modified reversal design compared an environmental and an environmental plus behavioral support intervention on lunchtime PA participation versus baseline levels in a suburban junior high school in the western United States (N = 1452). PA and related contextual data were collected using systematic observation.
Significantly more girls and boys were observed in PA during the interventions compared with baseline phases (F 2,1173 = 13.52, P < .0001, η2 = .023; F 2,1173 = 20.14, P < .0001, η2 = .033, for girls and boys, respectively). There were no significant differences between the environmental phase and the environment plus behavioral support phase.
Providing access and opportunity significantly increased the number of girls and boys observed in PA during a lunchtime program, with no additive effects of behavioral support. Further research into providing the individual-level contingencies at an institutional level is needed.
Christopher C. Imes, Yaguang Zheng, Dara D. Mendez, Bonny J. Rockette-Wagner, Meghan K. Mattos, Rachel W. Goode, Susan M. Sereika and Lora E. Burke
Background: The obesity epidemic is a global concern. Standard behavioral treatment including increased physical activity, reduced energy intake, and behavioral change counseling is an effective lifestyle intervention for weight loss. Purpose: To identify distinct step count patterns among weight loss intervention participants, examine weight loss differences by trajectory group, and examine baseline factors associated with trajectory group membership. Methods: Both groups received group-based standard behavioral treatment while the experimental group received up to 30 additional, one-on-one self-efficacy enhancement sessions. Data were analyzed using group-based trajectory modeling, analysis of variance, chi-square tests, and multinomial logistic regression. Results: Participants (N = 120) were mostly female (81.8%) and white (73.6%) with a mean (SD) body mass index of 33.2 (3.8) kg/m2. Four step count trajectory groups were identified: active (>10,000 steps/day; 11.7%), somewhat active (7500–10,000 steps/day; 28.3%), low active (5000–7500 steps/day; 27.5%), and sedentary (<5000 steps/day; 32.5%). Percent weight loss at 12 months increased incrementally by trajectory group (5.1% [5.7%], 7.8% [6.9%], 8.0% [7.4%], and 13.63% [7.0%], respectively; P = .001). At baseline, lower body mass index and higher perceived health predicted membership in the better performing trajectory groups. Conclusions: Within a larger group of adults in a weight loss intervention, 4 distinct trajectory groups were identified and group membership was associated with differential weight loss.