Swimmers depend on accessory breathing muscles for adequate ventilation. Pectoralis minor is an accessory breathing muscle. The daily repetition of gleno-humeral flexion and medial rotation results in adaptive shortening of Pectoralis, a common phenomenon in competitive swimmers. If Pectoralis minor is shortened the scapula is in an anteriorly tipped position. This anteriorly tipped position will affect scapula kinematics as well as the strength of Pectoralis minor to function as an accessory breathing muscle. One of the risk factors contributing to shoulder dysfunction in competitive swimmers is an altered scapular position. The study aimed to determine if lateral costal breathing dissociation exercises in conjunction with scapular retraining exercises had an effect on the position of the scapula in competitive swimmers. A comparative parallel group longitudinal design was used in this study. During a six week supervised intervention period the intervention group (n=28) and control group (n=30) did retraining of the scapula stabilisers and stretching of Pectoralis minor. The intervention group did breathing dissociation exercises to facilitate lateral costal breathing. No specific breathing exercises were facilitated within the control group. Pectoralis minor length and thoracic expansion had been measured. The function of the scapula stabilisers was evaluated. The resting as well as dynamic scapula positions were evaluated. Evaluations were done at baseline, six weeks and five months post intervention. Treatment groups were compared with respect to change from baseline to six weeks and baseline to five months in PMI, FVC and thoracic expansion utilizing analysis of covariance (ANCOVA) with covariates baseline reading. The intervention group showed an increase in the Pectoralis minor Index (PMI) of 0.5 (left & right) and the control group reflected an increase of 0.5 (left) and 0.7 (right). The intervention group reflected continuous improvement in PMI and the control group showed deterioration. In addition to the PMI upper thoracic, expansion decreased and lower thoracic expansion increased in the intervention group. The control group showed a decrease in upper and lower thoracic expansion. Groups were compared with respect to change from baseline to six weeks and five months respectively for categorical parameters, muscle function and scapula position (resting and dynamic) using Fisher’s exact test. After six weeks the intervention group showed significantly (p<0.04) less winging of the distal third of the scapula on the left side when compared to the control group. After five months the scapula showed significantly less tipping (p<0.02) during gleno-humeral flexion, on the left side. The McNemar test for symmetry had been applied to determine if any within group changes occurred. Within the intervention group ten of the thirteen markers used to determine the resting position of the scapula, reflected significant improvement compared to the six markers in the control group. Only the intervention group reflected remarkable improvement in function of the lower fibres of Trapezius muscle. Serratus anterior and middle fibres of Trapezius muscles showed significance within group improvement in function for both groups. The scapula showed significantly less dysrhythmia within the intervention group on the left and right sides (p< 0.0209) when compared to the control group. After five months the resting scapula position reflected deterioration for both groups. Dysrhythmia and winging of the scapula deteriorated from six weeks to five months for both groups. The muscle function of the lower fibres of Trapezius showed significance within group changes for both groups from six weeks to five months. The ability to contract Serratus anterior and the middle fibres of Trapezius agonistically was maintained from six weeks to five months. However the eccentric control and ability to contract the muscle without fatigue within the Serratus anterior and middle fibres of Trapezius showed deterioration from six weeks to five months for both groups. Conclusion: The increase in PMI and increase in lower thoracic expansion for the intervention group could favour swimmers to breathe more effectively. An increase in Pectoralis minor length resulted in a more posteriorly tipped scapula. This better positioned scapula promotes optimum function of the lower fibres of Trapezius. Contracting from a stable scapula, Pectoralis minor can fulfil its function as an accessory breathing muscle more effectively. / Thesis (PhD)--University of Pretoria, 2015. / tm2015 / Physiotherapy / PhD / Unrestricted

South African female swimmers have become a frequent feature in online media articles since zero female swimmers managed to qualify for the 2015 FINA World Championships and the 2016 Rio de Janeiro Olympic Games. Despite this being a valuable area to focus on, majority of the online articles reviewed have neglected to provide South African female swimmers with the opportunity to share their experiences, perceptions and personal interpretations on being a female swimmer in South Africa. As such, this research study explored the lived experiences of South African female student-athlete swimmers who are in the process of competing at an elite level. A qualitative research approach was utilised in this study, with interpretative phenomenological approach as its paradigmatic point of departure. One in-depth semi-structured interview was conducted with each of the eight South African female student-athlete swimmers from a swimming club located within a Tshwane-based university. Interpretative phenomenological analysis (IPA) was used to interpret the transcripts. Six main themes surfaced; the context, the body, the social and relational, the decision, career, and staying afloat. Along with this, numerous corresponding subthemes and two integrated themes (the emotional self and ways of thinking) also emerged from analysis. These themes highlighted the complexity of these participants’ lives as female student-athletes as well as South African female swimmers. These findings can assist coaches, parents, and other relevant role players to gain an enriched understanding of these participants’ experiences and needs so that they may better support and lead this population group; in doing so, they may be better equipped to reach their full potential. / Dissertation (MA)--University of Pretoria, 2019. / Psychology / MA / Unrestricted

El objetivo de esta investigación fue determinar la relación que existe entre los episodios de Flow y las habilidades psicológicas para el rendimiento en un grupo de 156 nadadores de competencia con edades comprendidas entre los 10 y 29 años. Para este propósito se utilizó la escala de Flow (García-Calvo, Jiménez, Santos-Rosa y Cervelló 2008) y el Inventario de Ejecución Deportiva (IPED) traducida al castellano por Raimundi, Reigal y Hernández (2016). Los resultados muestran una correlación positiva (Rho= .41, p< .01) entre la actitud hacia las capacidades de la escala de Flow y los pensamientos positivos del IPED; y entre las sensaciones durante la competencia de la escala de Flow y los pensamientos negativos. Así mismo, una correlación positiva (Rho= .31, p < .01) entre pensamientos positivos y negativos del IPED, y actitud hacia las capacidades y sensaciones durante la competencia. / The objective of this research was to determine the relationship between the episodes of Flow and the psychological skills for performance in a group of 156 competitive swimmers aged between 10 and 29 years. The Flow scale (García-Calvo, Jiménez, Santos-Rosa y Cervelló 2008) and the Sports Execution Inventory (IPED) translated into Spanish by Raimundi, Reigal y Hernández (2016) was used for this purpose. The results show a positive correlation (Rho= .41, p < .01) between the attitude towards the capacities of the Flow scale and the positive thoughts of the IPED, and between the sensations during the Flow scale competition and the negative thoughts. Likewise, a positive correlation (Rho= .31, p < .01) between positive and negative thoughts of the IPED, and attitude towards abilities and feelings during the competition. / Tesis

The purpose of this study was to determine the value, if any, of utilizing the instant playback feature of television videotape replay in teaching the front crawl and elementary backstroke to beginning swimmers at Utah State University. A review of literature revealed controversy as to the usefulness of the VTR media in teaching selected motor skills. Subjects consisted of 30 male freshmen and sophomore college students placed into two groups: experimental and control, on the basis of their individual scores on pr e -instruction skill testing. The subjects participated in 12 instructional period s of 40-50 minutes. The control group received instruction by a conventional method involving verbal explanation, demonstration, practice , instructor analysis and correction. The experimental group received the same type of instruction except that they were supplemented by the use of television videotape replay. Both test groups were taught by the same instructor. A panel of five judges evaluated videotaped performances of a pre and post skill test of each subject performing the two selected strokes. The judges rated four areas; proper arm movement, proper leg movement, arm-leg coordination and smoothness of style from l-1 0. The high score and low score for each subject was dropped and the raw score was determined by averaging the three middle scores of the five judges. An analysis of variance program was applied to the data with the pre test scores subtracted from the post test scores to determine performance differences . Sixty different observations were made on the 30 subjects , Summated analysis of variance was subjected to an F test for significance. The preset level of acceptance was . 05. The X change for both groups was 6. 24 with the experimental group having a higher mean than the control group; 6. 66 as compared with 5. 83 . The X reflects a positive learning curve for both groups . F tests for statistical significance indicated no difference between the means of the two test groups at any level of significance. It was concluded that the conventional method of instruction involving verbal explanation, demonstration, and correction is not benefited by the use of videotape replay in teaching the front c r awl and elementary backstroke to beginning swimmers.

Competitive swimmers frequently injure their shoulders. The risk factors for shoulder injuries in competitive swimmers have not been clearly identified. The primary purposes of this study were to describe the characteristics of female collegiate swimmers at the onset of a swim season, identify the risk factors of shoulder injury in female collegiate swimmers, characterize the swim volume of female collegiate swimmers, and determine if swim volume is a predictor of shoulder injury. A prospective longitudinal cohort multi-center design was utilized. Female collegiate swimmers [n=53, mean age=19.3+/– 1.2] from four NCAA Division II universities were recruited to participate in this study. Preseason screening data that included demographics and sport history, swimming characteristics, and a musculoskeletal assessment was collected on 106 shoulders. Participants completed a weekly survey to track exposure data over the course of the season. Shoulder injury data was also collected. A shoulder injury was defined as swimming-related shoulder pain that resulted in one or more limited or modified athletic practices or competitions. Female swimmers reported a history of shoulder pain in 18/106 (17.0%) shoulders, and 14/106 (13.2%) of swimmers presented with obvious scapular dyskinesis at preseason. No differences in shoulder characteristics were found between swimmers with a history of shoulder pain and those without and those with obvious dyskinesis compared to those with normal scapular motion. There was a positive correlation between anterior glenohumeral laxity and shoulder external rotation range of motion (r=0.37, p Previous injury was the sole predictor of new shoulder injury in the group studied. Further research into the predictors of shoulder injury in female collegiate swimmers is warranted.

No description available.

No description available.

published_or_final_version / Education / Master / Master of Education

Micron scale robots going inside our body and curing various ailments is a technolog¬ical dream that easily captures our imagination. However, with the advent of novel nanofabrication and nanocharacterization tools there has been a surge in the research in this field over the last decade. In order to achieve locomotion (swim) at these small length scales, special strategies need to be adopted, that is able to overcome the large viscous damping that these microbots have to face while moving in the various bod¬ily fluids. Thus researchers have looked into the swimming strategies found in nature like that of bacteria like E.coli found in our gut or spermatozoa in the reproductive mucus. Biomimetic swimmers that replicate the motion of these small microorganisms hold tremendous promise in a host of biomedical applications like targeted drug delivery, microsurgery, biochemical sensing and disease diagnosis. In one such method of swimming at very low Reynolds numbers, a micron scale helix has been fabricated and rendered magnetic by putting a magnetic material on it. Small rotating magnetic fields could be used then to rotate the helix, which translated as a result of the intrinsic translation rotation coupling in a helix. The present work focussed on the development of such a system of nanopropellers, a few microns in length, the characterization of its dynamics and velocity fluctuations originating from thermal noise. The work has also showed a possible application of the nanopropellers in microrheology where it could be used as a new tool to measure the rheological characteristics of a complex heterogeneous environment with very high spatial and temporal resolutions. A generalized study of the dynamics of these propellers under a rotating field, has showed the existence of a variety of different dynamical configurations. Rigid body dynamics simulations have been carried out to understand the behaviour. Significant amount of insight has been gained by solving the equations of motion of the object analytically and it has helped to obtain a complete understanding, along with providing closed form expressions of the various characteristics frequencies and parameters that has defined the motion. A study of the velocity fluctuations of these chiral nanopropellers has been carried out, where the nearby wall of the microfluidic cell was found to have a dominant effect on the fluctuations. The wall has been found to enhance the average level of fluctuations apart from bringing in significant non Gaussian effects. The experimentally obtained fluctuations has been corroborated by a simulation in which a time evolution study of the governing 3D Langevin dynamics equations has been done. A closer look at the various sources of velocity fluctuations and a causality study thereof has brought out a minimum length scale below which helical propulsion has become impractical to achieve because of the increased effect of the orientational fluctuations of the propeller at those small length scales. An interesting bistable dynamics of the propeller has been observed under certain experimental conditions, in which the propeller randomly switched between the different dynamical states. This defied common sense because of the inherent deterministic nature of the governing Stokes equation. Rigid body dynamics simulations and stability analysis has shown the existence of time scales in which two different dynamical states of the propeller have become stable. Thus the intrinsic dynamics of the system has been found to be the reason behind the bistable behaviour, randomness being brought about by the thermal fluctuations present in the system. Finally, in a novel application of the propellers, they have been demonstrated as a tool for microrheological mapping in a complex fluidic environment. The studies done in this work have helped to develop this method of active microrheology in which the measurement times are orders of magnitude smaller than its existing counterparts.

This study compared bone mineral index (BMI, gm/cm²) of the femur, spine, and radius, measured by photon absorptiometry in various groups of eumenorrheic female athletes. The sample included body builders (11), swimmers (13), runners (5 collegiate, 11 recreational), and inactive controls (18) averaging 25 years of age, ranging from 17 to 38 years. Lumbar vertebral BMI for body builders (1.40 gm/cm²) was significantly (p ≤ 0.05) greater than controls (1.25 gm/cm²). The body builders' femoral neck BMI (1.09 gm/cm²) was significantly greater than swimmers (0.97 gm/cm², recreational runners and controls (0.95 gm/cm²). Years of exercise history and calcium consumption were not significant predictors of BMI. Correlation coefficients between fat-free body and all BMI sites were significant and more closely related to bone mineral than other variables (weight, height, weight/height²). Correlation coefficients for proximal and distal radius BMI and femoral and spine BMI were significant, the distal radius having higher association.