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Becky L. Heinert, Thomas W. Kernozek, John F. Greany and Dennis C. Fater

Objective:

To determine if females with hip abductor weakness are more likely to demonstrate greater knee abduction during the stance phase of running than a strong hip abductor group.

Study Design:

Observational prospective study design.

Setting:

University biomechanics laboratory.

Participants:

15 females with weak hip abductors and 15 females with strong hip abductors.

Main Outcome Measures:

Group differences in lower extremity kinematics were analyzed using repeated measures ANOVA with one between factor of group and one within factor of position with a significance value of P < .05.

Results:

The subjects with weak hip abductors demonstrated greater knee abduction during the stance phase of treadmill running than the strong group (P < .05). No other significant differences were found in the sagittal or frontal plane measurements of the hip, knee, or pelvis.

Conclusions:

Hip abductor weakness may influence knee abduction during the stance phase of running.

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Sara Wilcox, Cheryl Der Ananian, Patricia A. Sharpe, Jennifer Robbins and Theresa Brady

Background:

Physical activity (PA) is important for arthritis self-management. A better understanding of the PA correlates in persons with arthritis will help inform interventions.

Methods:

Computer searches were conducted on PubMed, PsychInfo, Current Contents, and Cinahl databases. Reference lists of extracted articles were also searched. Thirty-six studies published between 1976 and February 2004 met inclusion criteria.

Results:

PA correlates are presented for sociodemographic, psychological, health-related, social, and environmental categories. Self-efficacy, perceived benefits and barriers, mental well-being, prior PA, and pain received the most consistent support as PA correlates, whereas sociodemographic, social, and environmental variables were the least studied. Too few studies were conducted to allow comparisons across arthritis type or study design.

Conclusions:

We recommend that additional qualitative research be conducted to understand factors influencing PA in persons with arthritis. Prospective studies, particularly in the context of a PA program or intervention, would also be useful to better understand how barriers and enablers change over time.

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Nico W. Van Yperen

This prospective study was designed to identify psychological factors that predict career success in professional adult soccer. Post hoc, two groups were distinguished: (1) Male soccer players who successfully progressed into professional adult soccer (n = 18) and (2) Male soccer players who did not reach this level (n = 47). Differences between the two groups were examined on the basis of data gathered in the initial phase of their careers, 15 years earlier. The psychological factors that predicted career success while statistically controlling for initial performance level and demographic variables were goal commitment, engagement in problem-focused coping behaviors, and social support seeking. On the basis of their scores on the significant predictor and control variables, 84.6% of the adolescent youth players were classified correctly as successful or unsuccessful.

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Joachim Stoeber, Mark A. Uphill and Sarah Hotham

The question of how perfectionism affects performance is highly debated. Because empirical studies examining perfectionism and competitive sport performance are missing, the present research investigated how perfectionism affected race performance and what role athletes’ goals played in this relationship in two prospective studies with competitive triathletes (Study 1: N = 112; Study 2: N = 321). Regression analyses showed that perfectionistic personal standards, high performance-approach goals, low performance-avoidance goals, and high personal goals predicted race performance beyond athletes’ performance level. Moreover, the contrast between performance-avoidance and performance-approach goals mediated the relationship between perfectionistic personal standards and performance, whereas personal goal setting mediated the relationship between performance-approach goals and performance. The findings indicate that perfectionistic personal standards do not undermine competitive performance, but are associated with goals that help athletes achieve their best possible performance.

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Caroline A. Macera and Wilma Wooten

This review summarizes information on the rate of injury among adolescents who participate in specific sports or recreational activities. Injury-related mortality is high among adolescents, accounting for over 75% of the deaths occurring among those between 15 and 19 years of age, with about 5% of these deaths attributed to sports injuries. Several difficulties were encountered in conducting this review. There was no standard definition for injury, resulting in widely diverse operational definitions. The underlying denominator and time period used to obtain rates also varied widely. In spite of these difficulties, several sports were identified as particularly dangerous due to the nature of the injury: football for males and gymnastics for females. Consistent injury definitions and larger prospective studies are needed to confirm these rates and to identify risk factors.

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Steriani Elavsky

This 2-year prospective study examined the exercise and self-esteem model in middle-aged women (N = 143) previously enrolled in a randomized controlled exercise trial. Across the 2-year period, increases in physical activity (PA) and self-efficacy and reductions in body mass index (BMI) were associated with improved subdomain self-perceptions relative to physical condition, and reductions in BMI were associated with improved subdomain self-perceptions relative to physical condition and body attractiveness. The effects of PA, self-efficacy, and BMI on changes in physical self-worth and global self-esteem were mediated by changes in self-perceptions relative to physical condition and body attractiveness. The results of this longitudinal analysis support the hierarchical and multidimensional structure of self-esteem and indicate that middle-aged women can enhance how they perceive their condition and body attractiveness by continued participation in physical activity, increasing their self-efficacy, and maintaining healthy BMI levels.

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Larry Tucker and Travis Peterson

Background:

This study was conducted to determine if cardiorespiratory fitness at baseline, and changes in fitness, influence risk of weight gain (≥3 kg) over 20 months. Another aim was to ascertain if potential confounding factors, including age, education, strength training, energy intake, and weight, influence risk of weight gain.

Methods:

In a prospective study of 257 women, fitness (VO2max) was assessed using a graded, maximal treadmill test at baseline and follow-up. Energy intake was measured using 7-day, weighed food records. Subjects were divided into quartiles based on fitness. Risk ratios were used to show the risk of weight gain among those who were fit at baseline compared with their counterparts.

Results:

Most women gained weight and 23% gained ≥3 kg. Mean VO2max was 35.7 ± 7.2 mL·kg−1·min−1. Women with low-fitness at baseline had 3.18 times (95% CI: 1.46 to 6.93) greater risk, and moderately fit women had 2.24 times (95% CI: 1.04 to 4.82) greater risk of weight gain than women in the high-fitness quartile. Adjusting for potential confounders had little effect on results.

Conclusions:

High levels of fitness seem to help protect middle-aged women against weight gain, whereas low and moderate fitness increase risk of weight gain over time.

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Benno M. Nigg, Edward C. Frederick, Michael R. Hawes and Simon M. Luethi

Pain, discomfort, and/or injuries in tennis can be influenced by the individual movement pattern and the external and/or internal boundary conditions. The influence of external boundary conditions on the occurrence of short-term pain was studied in a prospective study with 229 subjects. The boundary conditions investigated were shoe, temperature, type and length of game and subjective assessment of comfort, sole grip, and lateral stability Pain was reported by 40% of the 171 subjects included in the final analysis. It was frequently reported in the first two playing sessions but less frequently afterward. Discomfort was the dominant type of pain, accounting for 71.6% of all reported cases. The foot was the major site of pain (85%). The boundary conditions influencing pain were found to be the shoe (the more flexible shoe 1 had less pain than the suffer shoe 2), the type of game (competitive more than recreational), and the length of the game (longer playing sessions with more pain). Subjective assessment of comfort, sole grip, and lateral support also showed differences for the pain/no pain groups. Subjects who complained about these aspects were more frequently in the pain groups. The results show that the occurrence of pain in tennis can be influenced by various external boundary conditions.

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Felipe Fossati Reichert, Ana Maria Batista Menezes, Jonathan Charles Kingdom Wells, Ulf Ekelund, Fabiane Machado Rodrigues and Pedro Curi Hallal

Background:

Prospective studies on physical activity (PA), diet, and body composition in adolescents are lacking, particularly outside high-income countries.

Goals:

To describe the methods used to assess these variables in the 1993 Pelotas (Brazil) Birth Cohort and to discuss the fieldwork challenges faced and alternatives to overcome them.

Methods:

In 2006–07 a subsample of the 1993 Pelotas cohort was revisited. PA was estimated using questionnaires, a combined heart-rate and motion sensor (Acti-Heart), and the ActiGraph GT1M accelerometer. Diet was investigated by questionnaire. Total body water was determined by stable isotopes. Thirty individuals had their total energy expenditure assessed by doubly labeled water. All data were collected at participants’ home.

Results:

The logistics of the fieldwork and the difficulties in undertaking the study and alternatives to overcome them are presented. Preliminary analyses show that 511 individuals were traced (response rate = 90.0%). Compliance of both adolescents and their families for the motion sensors and body-composition measurements was excellent.

Conclusions:

The authors conclude that it is feasible to carry out high-quality studies on PA in developing countries. They hope the article will be useful to other researchers interested in carrying out similar studies.

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Javier Molina-García, Ana Queralt, Isabel Castillo and James F. Sallis

Background:

This study examined changes in multiple physical activity domains during the transition out of high school and psychosocial and environmental determinants of these changes.

Methods:

A 1-year prospective study was designed. The baseline sample was composed of 244 last-year high school students (58.6% female) from Valencia, Spain. Follow-up rate was 46%. Physical activity and potential determinants were measured by the Global Physical Activity Questionnaire and other evaluated scales in 2 waves.

Results:

Total physical activity and active commuting (AC) decreased, respectively, by 21% and 36%, only in males. At time 1, access to car/motorbike (inverse), planning/psychosocial barriers (inverse), street connectivity (positive) and parental education (inverse) were significantly associated with AC (P < .05). Prospectively, the increase in distance to school/workplace was associated with AC decrease among males (P < .001). In both genders, there was a decrease in leisure-time physical activity (LTPA; –35% in males, –43% in females). At time 1, self-efficacy and social support were positive correlates of LTPA (P < .05). Social support decreases were associated with reductions in LTPA for males (P < .05).

Conclusions:

Several psychosocial and environmental correlates of physical activity change were identified, and these are promising targets for interventions.