South African Journal of Sports Medicine最新文献

{"title":"Changes in training activity post COVID-19 infection in recreational runners and cyclists.","authors":"A Emeran,&nbsp;E V Lambert,&nbsp;T Paruk,&nbsp;A Bosch","doi":"10.17159/2078-516X/2022/v34i1a13758","DOIUrl":"https://doi.org/10.17159/2078-516X/2022/v34i1a13758","url":null,"abstract":"<p><strong>Background: </strong>Anecdotal evidence suggests that athletes struggle to return to exercise post COVID-19 infection. However, studies evaluating the effect of COVID-19 on athletes' exercise activity are limited.</p><p><strong>Objectives: </strong>The objectives of this study were: (i) to describe the perceptions of recreational runners and cyclists recovering from COVID-19 on their training activity and general well-being, (ii) to compare device-measured training data in runners and cyclists pre- and post COVID-19, with non-infected controls that had a training interruption.</p><p><strong>Methods: </strong>Participants who were recruited via social media completed an online questionnaire (n=61), including demographic, health and COVID-19 descriptive data. In a sub-sample, device-measured training data (heart rate, time, distance and speed, n=27) were obtained from GPS devices for four weeks before infection and on resumption of training. Similar data were collected for the control group (n=9) whose training had been interrupted but by factors excluding COVID-19.</p><p><strong>Results: </strong>Most participants experienced a mild to moderate illness (91%) that was associated with a training interruption time of two-four weeks. Decreases in heart rate, relative exercise intensity, speed, time and distance were observed during the first week of returning to training for both groups, followed by an increase from Week two onwards.</p><p><strong>Discussion: </strong>Results failed to support a 'COVID-19 effect' on exercise activity as reductions in training variables occurred in both the COVID-19 and control groups. A possible explanation for the reductions observed is a deliberate gradual return to training by athletes post-COVID-19.</p><p><strong>Conclusion: </strong>More research is needed using device-measured training data prior to and post COVID-19 infection to better understand the impact of the SARS-CoV-2 virus on the exercise activity of athletes.</p>","PeriodicalId":31065,"journal":{"name":"South African Journal of Sports Medicine","volume":"34 1","pages":"v34i1a13758"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9924504/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10766488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Do upper leg compression garments aid performance and reduce exercise-induced muscle damage in recreational marathon runners?","authors":"K M Kabongo,&nbsp;A Emeran,&nbsp;A N Bosch","doi":"10.17159/2078-516X/2022/v34i1a14169","DOIUrl":"10.17159/2078-516X/2022/v34i1a14169","url":null,"abstract":"<p><strong>Background: </strong>Despite the lack of scientific knowledge on the physiological and biomechanical effects of wearing compression garments (CGs), there has been an increase in the use of compression garments (CG) amongst endurance runners.</p><p><strong>Objectives: </strong>To compare marathon race performance, post-race pain, and mid-thigh circumference in marathon runners using upper leg CGs, with runners who did not use CGs in the same marathon race.</p><p><strong>Methods: </strong>The study was conducted on healthy, long-distance runners (n=18) participating in the Winelands Marathon race, Cape Town, South Africa. The CG group (n=10) participated in the race wearing upper leg CGs, while the control group (n=8) did not. Participants were tested on three occasions for various subjective markers of exercise-induced muscle damage (Visual analogue scale (VAS) pain rating score, and Likert scale for muscle pain), mid-thigh circumference for muscle swelling, and running performance (race pace).</p><p><strong>Results: </strong>VAS pain ratings for hamstring (p=0.04), knee flexion (p=0.02) and hip extension (p=0.04) were significantly lower than the ratings of the control group immediately post-race and two days post-race. No statistically significant differences were detected in race performance, mid-thigh circumferences or Likert scale for determination of muscle soreness.</p><p><strong>Discussion: </strong>Wearing of upper leg CGs while running a marathon race improved VAS pain ratings immediately post-race through to two days post-race. However, due to no placebo control, this beneficial effect may be psychological as opposed to a physiological effect of the CGs on muscle pain.</p><p><strong>Conclusion: </strong>The use of upper leg CGs reduced subjective muscle pain in runners in the first 48 hours post-race.</p>","PeriodicalId":31065,"journal":{"name":"South African Journal of Sports Medicine","volume":"34 1","pages":"v34i1a14169"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9924514/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10771129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of systematic exercise training on skeletal muscle strength in a patient with advanced inclusion body myositis: A case study.","authors":"C D'Alton,&nbsp;R Johnstone,&nbsp;C du Plessis,&nbsp;A Pursad,&nbsp;T A Kohn","doi":"10.17159/2078-516X/2022/v34i1a13145","DOIUrl":"https://doi.org/10.17159/2078-516X/2022/v34i1a13145","url":null,"abstract":"<p><p>Inclusion body myositis (IBM) is an inflammatory and degenerative autoimmune disease that targets specific muscle groups, causing severe muscle weakness. Exercise training is often contraindicated in myopathies as it may aggravate muscle damage and inflammation. Although some reported positive outcomes in muscle strength of early diagnosed IBM patients undergoing resistance training, there remains uncertainty as to whether exercise could be beneficial and safe in advanced stage IBM. Thus the aims of this research were to evaluate the safety and response of 16-weeks supervised resistance training on the health and muscle performance of an elderly participant diagnosed with advanced stage IBM. It was shown that the training had no adverse effects on the health of the patient. Muscle strength measured at eight weeks and on completion of the intervention, remained the same as at baseline. In conclusion, the exercise programme was found to be safe and seemed to maintain muscle strength in a patient with advanced stage IBM.</p>","PeriodicalId":31065,"journal":{"name":"South African Journal of Sports Medicine","volume":"34 1","pages":"v34i1a13145"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9924562/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10771131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SA Rugby Injury and Illness Surveillance and Prevention Project (SARIISPP): The Carling Currie Cup Premiership Competition, Injury Surveillance Report, 2021.","authors":"","doi":"10.17159/2078-516X/2022/v34i1a15259","DOIUrl":"10.17159/2078-516X/2022/v34i1a15259","url":null,"abstract":"","PeriodicalId":31065,"journal":{"name":"South African Journal of Sports Medicine","volume":"34 1","pages":"v34i1a15259"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9924578/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10765198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"'Do we know if we need to reduce head impact exposure?': A mixed-methods study highlighting the varied understanding of the long-term risk and consequence of head impact exposure across all stakeholders at the highest level of rugby union.","authors":"L T Starling,&nbsp;C McKay,&nbsp;M Cross,&nbsp;S Kemp,&nbsp;K A Stokes","doi":"10.17159/2078-516X/2022/v34i1a13839","DOIUrl":"https://doi.org/10.17159/2078-516X/2022/v34i1a13839","url":null,"abstract":"<p><strong>Background: </strong>One strategy to prevent and manage concussion is to reduce head impacts, both those resulting in concussion and those that do not. Because objective data on the frequency and intensity of head impacts in rugby union (rugby) are sparse, stakeholders resort to individual perceptions to guide contact training. It is unknown whether there is a level of contact training that is protective in preparing elite players for contact during matches.</p><p><strong>Objectives: </strong>This study aimed to describe how contact training is managed in elite male rugby, and how staff and players perceive contact training load and head impact load.</p><p><strong>Methods: </strong>This was a sequential explanatory mixed-methods study. Forty-four directors of rugby, defence coaches, medical and strength/conditioning staff and 23 players across all 13 English Premiership Rugby Union clubs and the National senior team participated in semi-structured focus groups and completed two bespoke questionnaires.</p><p><strong>Results: </strong>The study identified the varied understanding of what constitutes head impact exposure across all stakeholder groups, resulting in different interpretations and a range of management strategies. The findings suggest that elite clubs conduct low levels of contact training; however, participants believe that some exposure is required to prepare players and that efforts to reduce head impact exposure must allow for individualised contact training prescription.</p><p><strong>Conclusion: </strong>There is a need for objective data, possibly from instrumented mouthguards to identify activities with a high risk for head impact and possible unintended consequences of reduced exposure to these activities. As data on head impact exposure develop, this must be accompanied with knowledge exchange within the rugby community.</p>","PeriodicalId":31065,"journal":{"name":"South African Journal of Sports Medicine","volume":"34 1","pages":"v34i1a13839"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9924567/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10754707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The cycle ergometer test is not a reliable alternative to the countermovement jump in the assessment of power output.","authors":"K R Peyper,&nbsp;B Olivier,&nbsp;A Green","doi":"10.17159/2078-516X/2022/v34i1a12869","DOIUrl":"https://doi.org/10.17159/2078-516X/2022/v34i1a12869","url":null,"abstract":"<p><strong>Background: </strong>Rugby union is a physically demanding collision sport that requires optimal neuromuscular function for maximal power output, with mechanical power an integral component of performance. Peak power (P_p) and relative P_p are parameters of neuromuscular function commonly assessed through the countermovement jump (CMJ) as a measure of fatigue. The Wattbike cycle ergometer test (CET) is a non-load bearing method of evaluating lower limb power. The cost-effective CET could therefore offer a viable alternative to the CMJ.</p><p><strong>Objectives: </strong>This study aimed to determine the concurrent validity of the CMJ and CET.</p><p><strong>Methods: </strong>Thirty-eight professional rugby union players performed twelve CMJs on a force platform with four loads (bodyweight: BW-CMJ; 20kg: 20-CMJ; 40kg: 40-CMJ and 60kg: 60-CMJ) and a six second peak power (6PPO) CET assessment on a Wattbike ergometer.</p><p><strong>Results: </strong>CMJ power outputs were [BW-CMJ: P_p - 3101±648 W; 20-CMJ: P_p - 2724±513 W; 40-CMJ: P_p - 2490±496 W; 60-CMJ: P_p - 2238±366 W] and CET [P_p - 1310±161 W]. None of the CMJ-P_p values showed relationships with any CET power variables. Large (r = 0.51-0.63; p = 0.000 - 0.001) relationships were found to be between relative CMJ and relative CET power outputs. Bland-Altman plots, which were used to determine the level of agreement between the two assessments, showed the agreement between the tests was poor.</p><p><strong>Conclusion: </strong>Though positive relationships existed between relative CMJ and relative CET power variables, analyses of the level of agreement in the Bland-Altman plots suggest that the two power assessment methods are not interchangeable measures of power.</p>","PeriodicalId":31065,"journal":{"name":"South African Journal of Sports Medicine","volume":"34 1","pages":"v34i1a12869"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9927866/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10765197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of wearable resistance load placement on neuromuscular activity and stride kinematics: A preliminary study.","authors":"M Brown,&nbsp;C Giroux,&nbsp;M Lacome,&nbsp;C Leduc,&nbsp;K Hader,&nbsp;M Buchheit","doi":"10.17159/2078-516X/2022/v34i1a13102","DOIUrl":"10.17159/2078-516X/2022/v34i1a13102","url":null,"abstract":"<p><strong>Background: </strong>Wearable resistance (WR) training is a modality that allows athletes to perform loaded sport-specific movements to develop force and power outputs. The acute responses by which WR works is still relatively unknown, and the effects of WR load and location of the load has not yet been examined.</p><p><strong>Objectives: </strong>To investigate the acute neuromuscular and stride characteristic responses to different wearable resistance (WR) loads and placements on the calf muscles during high-speed running.</p><p><strong>Methods: </strong>Ten well-trained subjects completed a workout of ten sets of three 10s runs at 18km.h^-1 (20s of rest between runs and one min between sets). Five conditions were tested: (1) unloaded control, (2) bilateral 0.75 vs. 1.5% body mass (BM) loading on the distal posterior calf, (3) bilateral proximal vs. distal loading of 1.5% BM positioned posteriorly, (4) bilateral anterior vs. posterior loading of 1.5% BM positioned distally, (5) unilateral loading of 1.5% BM on the distal posterior calf. Data were collected using Electromyography (EMG) and back-mounted GPS-embedded accelerometers. Magnitude of differences of within athlete and between muscle comparisons were calculated using effect sizes (ES) ± 90% confidence limits (CL).</p><p><strong>Results: </strong>No substantial differences in accelerometry data were observed between any of the loaded conditions and the control. EMG activity was lower for proximal loading compared to the control for the gluteus maximus (ES±90%CL; -0.72±0.41), vastus lateralis (-0.89±0.47) and vastus medialis (VM) (-0.97±0.46). Anterior loading induced substantially lower EMG activity for the semitendinosus (-0.70±0.48) and VM (-0.64±0.39) muscles compared with the control. EMG activity of the VM (-0.73±0.46) muscle was also substantially lower for posterior loading compared to the control. Unilateral loading induced no substantial differences in EMG activity between the loaded and unloaded legs.</p><p><strong>Conclusion: </strong>This preliminary study has provided a rationale for the performance of further investigations into the effects of WR lower limb loading on stride characteristics and EMG activity from a chronic standpoint using a larger population.</p>","PeriodicalId":31065,"journal":{"name":"South African Journal of Sports Medicine","volume":"34 1","pages":"v34i1a13102"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9924529/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10766484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acetabular fracture after cycling related falls: High index of suspicion is required to avoid missing the injury on plain radiographs.","authors":"J Swart,&nbsp;M Horak,&nbsp;R de Villiers,&nbsp;C Oberholzer,&nbsp;A Rotunno","doi":"10.17159/2078-516X/2022/v34i1a14526","DOIUrl":"https://doi.org/10.17159/2078-516X/2022/v34i1a14526","url":null,"abstract":"<p><p>Cycling participation as a medium of transport and as a competitive sport has steadily increased in recent decades. Traumatic injuries secondary to falls and collisions occur relatively frequently. Fractures of the hip and pelvis are uncommon with no studies to date reporting their exact incidence in this sport. Injuries specific to the acetabulum are reported even less frequently. We present four cases that highlight the insidious nature of acetabular fractures in cyclists and document their management and recovery. The number of acetabular fractures following falls from bicycles directly onto the lateral hip result in a relatively high number of fractures. Many of these may be missed due to the absence of findings on plain x-ray imaging.It is therefore important to have a high index of suspicion for hip and pelvis fractures when treating cycling related traumatic injuries.</p>","PeriodicalId":31065,"journal":{"name":"South African Journal of Sports Medicine","volume":"34 1","pages":"v34i1a14526"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9924554/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10754702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bilateral patellar tendon rupture in a weightlifter during an acute high-loading resistance exercise bout: A case study.","authors":"L A Alexander,&nbsp;J T Mchunu,&nbsp;R D Kgabu,&nbsp;E W Derman","doi":"10.17159/2078-516X/2022/v34i1a11781","DOIUrl":"https://doi.org/10.17159/2078-516X/2022/v34i1a11781","url":null,"abstract":"<p><p>Bilateral patellar tendon ruptures are exceedingly uncommon, especially when they occur in individuals without predisposing risk factors or systemic disease. Due to its rarity, many cases are missed on initial presentation resulting in poor patient outcomes. Identifying associated risk factors aids in diagnosis and mitigates this oversight. We report a case of a healthy, recreational weightlifter who sustained bilateral patellar tendon ruptures during an acute high-loading resistance exercise bout. We discuss how a spike in acute workload may have predisposed our patient to this injury. Research into training load and athlete injury risk is currently in vogue, however, no studies have analysed whether poor load management increases the risk of tendon ruptures. This case prompts awareness for clinicians who diagnose and manage this injury and helps to stimulate the formation of educational initiatives for athletes and coaches, aimed at injury prevention.</p>","PeriodicalId":31065,"journal":{"name":"South African Journal of Sports Medicine","volume":"34 1","pages":"v34i1a11781"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9924605/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10754704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heat shock protein response during fixed intensity and self-paced exercise in the heat in young, healthy women on oral contraceptives compared with young healthy men.","authors":"K J Onus,&nbsp;J Cannon,&nbsp;F E Marino","doi":"10.17159/2078-516X/2022/v34i1a11757","DOIUrl":"https://doi.org/10.17159/2078-516X/2022/v34i1a11757","url":null,"abstract":"<p><strong>Background: </strong>Heat shock proteins respond to a variety of physiological and environmental stresses, including heat stress, ischemia and endotoxic shock. Hormonal changes during the female menstrual cycle can have a thermogenic effect on body temperature. The monophasic oral contraceptive (OC) pill provides low doses of progesterone and oestrogen over the course of the normal menstrual phase. There is little evidence regarding the combined effects of OC on exercise performance and heat stress with respect to heat shock protein response.</p><p><strong>Objectives: </strong>This study aimed to determine the response of heat shock proteins (Hsp72) during fixed-intensity and self-paced exercise in the heat in young, healthy women on oral contraceptives compared with young healthy men.</p><p><strong>Methods: </strong>Sixteen physically active men and women performed 30 min fixed-intensity cycling at 50% of maximum workload, followed by 30 min of a self-paced time trial (TT) interspersed by 30 s maximal sprint at 9, 19 and 29 min respectively. Trials were undertaken in cool (20°C; 48±3% relative humidity (RH)) and warm (32°C; 66±2% RH) ambient conditions. Core (<i>T</i> _c) and skin temperature, heart rate (HR) and subjective responses were measured before, during and post exercise.</p><p><strong>Results: </strong>The distance, mean and peak power output, mean and peak speed during the self-paced time trial showed no difference between the ambient temperatures for men and women. Hsp72 in females was higher than males at all sample points at both 20°C and 32°C, except for pre-exercise at 20°C (<i>p</i>< 0.04). Women also attained a higher <i>T</i> _c than men at the end of the TT in the heat (38.5°C v 37.9°C for women and men, respectively; <i>p</i><0.03), higher mean HR and perceived exertion.</p><p><strong>Conclusion: </strong>This study indicates that females who use oral contraceptives (OC) had higher levels of Hsp72 than males when tested under the same environmental conditions.</p>","PeriodicalId":31065,"journal":{"name":"South African Journal of Sports Medicine","volume":"34 1","pages":"v34i1a11757"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9924522/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10761908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}