Thesis (M.A.)--York University, 2001. Graduate Programme in Kinesiology and Health Science. / Typescript. Includes bibliographical references (leaves 96-108). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ67722.

Title: Relationship of Energy Balance and Body Composition in Elite Female Gymnasts Background: Studies suggest that athletes participating in weight-specific and appearance-based sports, including gymnasts, are at risk for developing negative energy balance both during and at the end of the day. A prolonged state of negative energy balance has been associated with lower fat-free mass, higher fat mass, and lower bone mineral density. Energy balance is defined as energy in minus energy out, and has been viewed in the past as a static, 24-hour system that begins anew each day. This study examined the relationship of energy balance and body composition (lean body mass, fat mass, body fat percent) and bone mineral density. Studies evaluating the relationship between energy balance and body composition have been conducted in the past, but few have taken into consideration hourly energy balance and the effects of multiple time periods of energy deficit of < -400kcal. Purpose: The purpose of this study was to assess the relationship between energy balance and body composition in female gymnasts. Methods: This study utilized a secondary analysis of existing data, and included 23 female elite, nationally ranked, gymnasts. Participants were included in this analysis if they had completed three-day food and activity records and had full body DEXA scans. The food and activity records were analyzed using NutriTiming®, which predicts RMR via the Harris-Benedict equation, uses a MET-based relative intensity activity scale, and accesses the USDA Nutrient Database for Standard Reference, Release 26. NutriTiming provides both 24-hour and hourly energy balance values. Original data were collected as part of a study conducted at Georgia State University in 1993 that had received IRB-approval. The current study also received IRB approval. Results: Subject characteristics (mean ± SD) were: age (15.1 ±1. 58 years), height (151.3 ±7.7cm), and weight (45.63 ±8. 31kg). Average energy intake during the three days examined was 1375 kcal (±405), and the average predicted energy expenditure was 2430 kcal (± 298), for an energy balance of -1053 (± -438). Subjects were in a negative energy balance state the majority of the days analyzed. Spearman rho analysis found significant negative correlations between kcal consumed per kg bodyweight and body fat percent (r= -0.603, p=0.002), bone mineral density (r= -0.577, p=0.004), fat mass (r= -0.556, p=0.006), lean body mass (r= -0.466, p=0.025), lean body to height ratio (r= -0.466, p=0.025), and weight (r=-0.633, p=0.001). A significant amount of variance (R2= 0.435; SEE= ±0.05919, p=0.001) was explained in bone mineral density (dependent variable) with fat mass (independent variable). Conclusion: The associations in this study are consistent with previous studies evaluating the relationships between energy balance deficits and body composition, indicating that poor energy balance is associated with lower lean and higher fat mass. Lean body mass, fat mass, and BMD were positively correlated with age, but 24-hour energy balance was negatively correlated with age (r= -0.484; p=0.019), suggesting that, although growing, subjects were consuming less energy with increasing age.

The purpose of this study was to examine affective changes which result from injury in female collegiate gymnasts, using the Profile of Mood States (POMS) instrument (McNair, Lorr, & Droppleman, 1971 ). Twelve female gymnasts, comprising the Utah State University gymnastics team, completed the POMS twice per month for four months during their 1986-87 competitive season . A comparison group of 12 non-athlete female college students, matched with the gymnasts by age, year in school, and major, completed the POMS on the same schedule as the gymnasts. Injury was defined as orthopedic damage to the gymnast's body as a result of participation in gymnastics, another sport-related activity, or a non-sport-related accident, which forced the gymnast to miss one week of gymnastics practice or one competitive event. Pre- and post-injury POMS profiles were analyzed by visual inspection. Of the four gymnasts who sustained injuries during the season, two exhibited significant POMS profile changes. One gymnast who did not participate during the 1986-87 season, due to an injury sustained the previous year, produced POMS profiles which fluctuated in anticipation of, and in response to, her visits to physicians treating her injury. Comparisons using 1 tests of POMS factor scores of the non-injured gymnasts with those of the non-athlete college students indicated no significant differences between the two groups. Visual comparisons were conducted to ascertain if non-injured gymnasts' POMS profiles were similar to the "iceberg" profile found by Morgan (1979) in his study of elite athletes. Thirty-six percent of the gymnasts' POMS profiles had the iceberg configuration, as compared to 20 percent of the non-athletes' profiles. Since three of the five (60 percent) of the injured gymnasts in this study had significant changes in POMS factor scores, the hypothesis that injury can produce substantial affective changes in female collegiate gymnasts was supported . Additional research should be conducted to replicate and extend these results and to explore options for optimal treatment of injured athletes. Further comparisons between POMS profiles of both injured and healthy elite, professional, and collegiate athletes is recommended.

Introduction: In gymnastics, athletes perform twisting and flipping skills at high angular velocities. These athletes rely heavily on sensory information from the visual, proprioceptive, and vestibular systems. The vestibulo-ocular reflex (VOR) is responsible for stabilizing the visual field on the retina during head movement. To accomplish this, the eyes are reflexively moved in a direction opposite the head. In a twisting gymnast, this actually reduces the ability of gymnasts to see the landing during airborne skills. Hence it becomes necessary for the gymnasts to cancel or suppress their VOR in order to view the landing. Objective: The purpose of this research is to investigate the relationship between gymnastics skill level and their ability to suppress the VOR. Methods: Ten female gymnasts (mean age 15±2.2) were obtained via a sample of convenience from a local club. The sample included both competitive and recreational gymnasts. Subjects were asked to wear a measurement system that could track head and eye movements as they performed a series of visual tasks. Three experiments were performed: (1) a saccadic experiment – two horizontally fixed LEDs (±10°) were alternately lit in a non-predictable pattern to provide visual cues, (2) a VOR experiment – the subject was asked to perform yawl head movements to an audible metronome beat 11 while visually fixating on an LED target 1m away, and (3) a vestibulo-ocular reflex suppression/cancellation (VORc) experiment – a laser pointer was fixed to the subject‟s helmet close to the cyclopean eye (slaving the target to the head movement) and the subject was again asked to perform head movements to a metronome while visually fixating on the target. In both VOR experiments, the metronome frequency varied from 72 to 196 beats per minute. Eye and head position data were synchronously sampled at 250 and 100Hz respectively. Data were post-processed using MATLAB. Periodic calibrations were performed throughout the experiment to test the continued reliability of the data. Results: Saccadic peak velocities and latencies were calculated for the sample population. Their performance did not differ from the normal population. VOR and VORc gains were also calculated and compared. The higher level (competitive) gymnasts were better at suppressing their VOR. In addition, left/right VOR gain asymmetries correlated highly with twist direction in seven of the competitive gymnasts. Discussion/Conclusions: There is a correlation between VOR performance and gymnastic level. These results do not suggest that VOR differences develop as a result of practice. These differences may simply allow some individuals to become better performers. A longitudinal study on a larger population would be required to test the causal relationship between these variables.

Abstract available in the /Estimation_of_Power_Output_from_Static_and.1896.aspx">Medicine & Science in Sports & Exercise.

The purpose of the investigation was to determine the effect of self-modeling on self-efficacy and performance of balance beam routines. Subjects (n=ll) were intermediate level gymnasts rated at the 5, 6, and 7 skill levels with ages ranging from 8 to 13 years. Subjects were randomly assigned to one of two groups, a self-modeling or a control group. For the self-modeling group, self-modeling videotapes were made of each subject performing her balance beam routine. During a six week period, the self-modeling group subjects viewed the videotape of themselves prior to practice three times a week for six consecutive weeks. All subjects completed two different self-efficacy inventories and a balance beam skills test at four intervals: a pretest, a 2-week test, a 4 week-test, and a posttest. During the six weeks, each group participated in their normal instructional program at the gymnastics academy.The results of this study indicated no significant differences in ratings of self-efficacy or balance beam performance, as based on judge's ratings between the self-modeling group and the control group. However, a significant correlation was found between predicted performance scores and actual performance scores for the self-modeling group (r=.92). This correlation was not significant for the control group (r=.02). Even though a significant effect of self-modeling on self-efficacy and performance scores was not found, this significant correlation indicates that self-modeling may enhance a subject's ability to realistically assess her/his performance. Thus, self-modeling may benefit the learner by developing an accurate conception of one's performance which would enhance the ability to understand and utilize instructional feedback to improve performance. / School of Physical Education

The purpose of this study was to compare the effectiveness of cryotheapy versus no treatment in preventing blistering and tearing of the hands of twenty-six male college age gymnastics students at Utah State University. The subjects were tested with a hand dynamometer to determine differences in grip strength between right and left hands. Two groups of thirteen subjects each were formed to equalize the differences in grip strength. During the experimental period of four class sessions totaling two hours, subjects participated in various activities on the horizontal bar, parallel bars, anG rings which rec.,ui red simultaneous gripping by both hands. Whenever a subject experienced a burning sensation in the skin of his hands, he went immediately to tn ice water bath (100 C) and soaked one hand for thirty seconds. One group treated only the stronger hand, while the other group treated only the weaker hard. After treatment, the hand was dried and workout continued. When the skin tore on a subject's hand, he reported to the recorder and treated the tear by carefully trimming away a ll the loose skin. He was a lso encouraged to apply a disinfectant. The tear was measured and given a classification as to whether it was a 1st, 2nd, or 2rd degree tear, with a corresponding weighted value. Training continued unless the tear was serious. The data was subjected to the t distribution test for significance to de!ermine whether the cryotherapy was successful in preventing tearing of the skin on the treated hand. The res ul ts of the t test indicated a significant reduction in the amount of tearing that occurred on the treated hands of the subjects . Results of the t test for two sample means showed that there was no significant difference whether a subject treated the weaker hand or the stronger hand at the . 05 level of significance.

This study describes bone mineral index (g/cm²) of the distal and mid forearm, spine and hip in gymnasts/weight trainers, and runners with varying menstrual status. 12 eumenorrheic gymnasts/weight trainers (EGW), 11 eumenorrheic runners (ERU), 8 oligomenorrheic gymnasts/weight trainers (OGW), 3 oligomenorrheic runners (ORU) 4 amenorrheic runners (ARU) and a eumenorrheic control group (EC) of 18 subjects were examined. Bone mineral index (BMI) was measured using single and dual photon absorptiometry. EGW had greater BMI than ARU and EC (spine, hip and distal and mid forearm) and ERU (femur and distal forearm). The ARU were not significantly lower in BMI than the ERU. The ARU were only significantly lower in BMI than the EC at the distal forearm. OGW were not significantly greater in BMI than ORU. The OGW had greater BMI than the ARU (spine, femur and distal forearm), ERU and EC (femur and distal forearm). These results show higher BMI in gymnasts/weight trainers, independent of menstrual status, than in runners and controls.

This study used cinematography to determine differences in velocity, acceleration, moments of force, and body centers of gravity in four different positions of two techniques of the long-hang kip. Three female gymnasts performed five attempts of each technique: the traditional method, with an arch in the lower back at the end of the forward swing, and approximate shoulder angle of 180 degrees or more; and the newer method, with no arch in the lower back and approximate shoulder angle of 90 degrees or less. Three. USGF-rated judges scored the kips, and due to inability to distinguish between the two techniques, two subjects were eliminated. Major differences occurred in the swing extension, with the newer technique producing more velocity and a higher center of gravity throughout the movement.

Research on burnout has typically focused on individuals in the human service or helping occupations, More recently studies and conceptual models have appeared investigating burnout in the athletic environment, The bulk of research 011 athletic burnout has been conducted on coaches and, consequently, there is a dearth of empirical research on athlete burnout. 'the present study compared tennis players with gymnasts to determine which group is more likely to experience a higher incidence of burnout. The study also sought to investigate whether any relationship was evident between sport specific factors on the one hand, and burnout, tedium and psychological distress on the other. Three objective questionnaires consisting of the Maslach Burnout Inventory (MDI). Tedium measure and General Health Questionnaire 28 item scale (GHQ-28), as well as a sport specific questionnaire developed by the author, were used to collect data from 20 provincial and national tennis players (10 male and 10 female) and 20 provincial and elite gymnasts (10 male and 10 female). Statistical analysis of the questionnaires revealed a number of important findings. It was found that sport group was not a significant factor in the assessment of athlete burnout. Gender, however, was highly significant with females more likely to experience burnout than males. It was shown that females experience low levels of sport enjoyment, social support and personal accomplishment and high levels of sport pressure, emotional exhaustion, depersonalisation, tedium and psychological distress. Key relationships were further identified between the sport specific variables of sport enjoyment, social support and sport pressure, and the burnout, tedium and psychological distress variables. Negative sport performance such as low enjoyment and social support and heightened feelings of sport pressure were strongly related to high levels of burnout, tedium and psychological distress. Recommendations for future research are made on the basis of these findings.