Journal of sports science & medicine最新文献

{"title":"Challenges in Maintaining Emotion Regulation in a Sleep and Energy Deprived State Induced by the 4800Km Ultra-Endurance Bicycle Race; The Race Across AMerica (RAAM).","authors":"Ian M Lahart,&nbsp;Andrew M Lane,&nbsp;Andrew Hulton,&nbsp;Karen Williams,&nbsp;Richard Godfrey,&nbsp;Charles Pedlar,&nbsp;Mathew G Wilson,&nbsp;Gregory P Whyte","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Multiday ultra-endurance races present athletes with a significant number of physiological and psychological challenges. We examined emotions, the perceived functionality (optimal-dysfunctional) of emotions, strategies to regulate emotions, sleep quality, and energy intake-expenditure in a four-man team participating in the Race Across AMerica (RAAM); a 4856km continuous cycle race. Cyclists reported experiencing an optimal emotional state for less than 50% of total competition, with emotional states differing significantly between each cyclist over time. Coupled with this emotional disturbance, each cyclist experienced progressively worsening sleep deprivation and daily negative energy balances throughout the RAAM. Cyclists managed less than one hour of continuous sleep per sleep episode, high sleep latency and high percentage moving time. Of note, actual sleep and sleep efficiency were better maintained during longer rest periods, highlighting the importance of a race strategy that seeks to optimise the balance between average cycling velocity and sleep time. Our data suggests that future RAAM cyclists and crew should: 1) identify beliefs on the perceived functionality of emotions in relation to best (functional-optimal) and worst (dysfunctional) performance as the starting point to intervention work; 2) create a plan for support sufficient sleep and recovery; 3) create nutritional strategies that maintain energy intake and thus reduce energy deficits; and 4) prepare for the deleterious effects of sleep deprivation so that they are able to appropriately respond to unexpected stressors and foster functional working interpersonal relationships. Key PointsCompleting the Race Across AMerica (RAAM); a 4856km continuous cycle race associated with sleep disturbance, an energy-deficient state, and experiencing intense unwanted emotions.Cyclists reported experiencing an optimal emotional state for less than 50% of total competition and actual sleep and sleep efficiency was better maintained during longer rest periods.We suggest that future RAAM cyclists and crew should:Identify individual beliefs on the perceived functionality of emotional states in relation to best (optimal) and worst (dysfunctional) performance as the starting point to identifying if emotion regulation strategies should be initiated.Plan for enhanced sleep and recovery not just plan and train for maintaining a high average velocity;Create nutritional strategies that maintain energy intake and thus reduce energy deficits;Psychologically prepare cyclists and crew for the deleterious effects of sleep deprivation so that they both are able to appropriately respond to unexpected stressors and foster functional interpersonal working relationships. </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"481-8"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772592/pdf/jssm-12-481.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40259109","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":"Microcirculation Under an Elastic Bandage During Rest and Exercise - Preliminary Experience With the Laser-Doppler Spectrophotometry System O2C.","authors":"Björn Sommer,&nbsp;Gereon Berschin,&nbsp;Hans-Martin Sommer","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>There is an abundace of studies on the influence of rest and exercise as well as external compression on cutaneous, subcutaneous and muscle tissue blood flow using different measurement techniques. As a novel approach, we simultaneously examined the influence of a custom- made elastic thigh bandage on cutaneous and subcutaneous venous blood oxygenation (SO2), postcapillary venous filling pressures (rHb) and blood flow (flow) using the non-invasive laser- Doppler spectrophotometry system \"Oxygen-to-see(O2C)\". Parameters were obtained in 20 healthy volunteers in 2 mm and 8 mm tissue depth during rest, 5 and 10 minutes of moderate bicycle exercise following a 10-minute recovery period. Without the bandage, results matched the known physiological changes indicating higher blood backflow from superficial and deep veins. Underneath the elastic bandage, we observed lower post-capillary filling pressures during exercise. However, after the bandage was removed in the post-exercise period, all obtained parameters of microcirculation remained increased, indicating a higher amount of local venous blood volume in this area. Our observations might be the result of external compression, thermoregulatory and exercise-dependent vascular mechanisms. With the O2C device, a promising new non- invasive technique of measuring local microcirculation in soft tissue exists. This study gives new insights in the field of non-invasive diagnostics with special regard to the influence of elastic bandages on local microcirculation. Key PointsIt can be demonstrated that a novel non-invasive laser-Doppler spectrophotometry system allows the determination of capillary-venous microcirculation in an in-vivo study during exercise-rest cycles.The results received with this technique indicate that a) without an elastic thigh bandage, turnover rates of capillary and post-capillary microperfusion in skin and subcutaneous fat tissue increase under physical exertion, b) skin blood flow decreases while subcutaneous blood flow remained constant in the subsequent recovery phase. While wearing the bandage, c) venous back flow during exercise is increased, whereas d) in the recovery phase, microcirculation remained increased in both tissue depths after removing the bandage.In conclusion, the elastic bandage has a negative impact on local microcirculation and capillary-venous back flow, which is possibly due to a displacement of blood volume into the deep venous system and heat accumulation impairing the thermoregulatory response at the same time. </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"414-21"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772583/pdf/jssm-12-414.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40257176","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":"Familiarization Effects of an Elliptical All-out Test and the Wingate Test Based on Mechanical Power Indices.","authors":"Ozgur Ozkaya","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The Wingate all-out test (WAT) is commonly used to estimate anaerobic capabilities of athletes by using an upper or lower body cycle ergometer, however, a new test modality called elliptical all-out test (EAT) which measures activated whole-body locomotor tasks has recently been proposed. The purpose of this study was to evaluate the familiarization effects of a 30-s EAT versus WAT. Twenty male trained athletes performed pre-familiarization (Trial- I), post-familiarization (Trial-II) and retest of Trial-II (Trial-III) sessions on both cycle ergometer and elliptical trainer. Peak power (PP), average power (AP), power drop (PD) and fatigue index ratio (FI%) were analyzed using student's t-test for paired samples and correlated by intra-class correlation coefficients (ICC). Moreover, an error detection procedure was administered using data attained from illogical interrelations among 5-s segments of 30-s tests. The main results showed that there were significant familiarization effects in all mechanical power outputs obtained from Trial-I and Trial-II in both EAT (ICC = 0.49-0.55) and WAT (ICC = 0.50-0.57) performances (p ≤ 0.01). Significant segmental disorders were detected in power production during Trial-I of EAT, however, none existed in any of test trails in the WAT (p ≤ 0.001). After familiarization sessions, reliability coefficients between Trial-II and Trial-III showed moderate to strong-level agreements for both EAT (ICC = 0.74-0.91) and the WAT (ICC=0.76-0.93). Our results suggested that prior to the performance tests, combination of a well designed familiarization session with one full all-out test administration is necessary to estimate the least moderately reliable and accurate test indices for both WAT and EAT. Key PointsA well designed familiarization session, and then, one additional all-out test administration, several days prior to main test, is suggested to estimate more accurate and reliable retest correlations for both cycling and elliptical all-out test modalities.Because of greater muscle recruitment and different movement pattern, familiarization seems more effective for a 30-s all-out test performed on an elliptical trainer compared to a cycle ergometer. </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"521-5"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772597/pdf/jssm-12-521.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40258512","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 physiological demands of table tennis: a review.","authors":"Miran Kondrič,&nbsp;Alessandro Moura Zagatto,&nbsp;Damir Sekulić","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Although table tennis has a tradition lasting more than 100 years, relatively little is known about players' physiological requirements - especially during competition. In this review we discuss research studies that have led to our current understanding of how the body functions during table tennis training and competition and how this is altered by training. Match and practice analysis of the table tennis game indicates that during intense practice and competition it is predominantly the anaerobic alactic system that is called into play, while the endurance system is relied on to recovery the anaerobic stores used during such effort. It is thus important for coaches to keep in mind that, while the anaerobic alactic system is the most energetic system used during periods of exertion in a table tennis game, a strong capacity for endurance is what helps a player recover quicker for the following match and the next day of competition. This paper provides a review of specific studies that relate to competitive table tennis, and highlights the need for training and research programs tailored to table tennis. Key PointsMatch and practice analysis of the table tennis game indicates that during intense practice and competition it is predominantly the anaerobic alactic system that is called into play.The endurance system is relied on to recovery the anaerobic stores used during hard practice and competition effort.It is important for coaches to keep in mind that, while the anaerobic alactic system is the most energetic system used during periods of exertion in a table tennis game, a strong capacity for endurance is what helps a player recover quicker for the following match and the next day of competition. </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"362-70"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772576/pdf/jssm-12-362.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40255697","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 association between physical activity and sex-specific oxidative stress in older adults.","authors":"Masaki Takahashi,&nbsp;Masashi Miyashita,&nbsp;Jong-Hwan Park,&nbsp;Hyun-Shik Kim,&nbsp;Yoshio Nakamura,&nbsp;Shizuo Sakamoto,&nbsp;Katsuhiko Suzuki","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Oxidative stress increases with advancing age and is a mediator of several diseases including cancer, cardiovascular disease, and diabetes. Moreover, postmenopausal women have a lower estrogen concentration, which is associated with elevated oxidative stress. However, there is no definitive evidence regarding the relationship between daily physical activity and oxidative stress status in older adults, including postmenopausal women. Twenty-nine adults (age, 70.1 ± 1.0 years, mean ± SE; 12 women and 17 men) were examined in this cross-sectional study. Prior to blood collection, the participants were asked to wear a uniaxial accelerometer for 4 consecutive weeks to determine their level of physical activity. After a 48-h period of physical activity avoidance and a 10-h overnight fast, venous blood samples were obtained from each participant. Fasting plasma derivatives of reactive oxygen metabolites (d-ROMs) and malondialdehyde (MDA) concentrations of oxidative stress markers were negatively correlated with the amount of physical activity in women (d-ROMs; r = -0.708, p = 0.002) (MDA; r = -0.549, p = 0. 028), but not in men. Fasting plasma biological antioxidant potential of antioxidant capacity marker was positively correlated with the amount of physical activity in women (BAP; r = 0.657, p = 0.006) (GSH; r = 0.549, p = 0.028), but not in men. Moreover, superoxide dismutase activity of antioxidant capacity marker was positively correlated with the amount of physical activity in men (r = 0.627, p = 0.039), but not in women. There were no associations between physical activity and other oxidative stress markers (reduced and oxidized glutathione, glutathione peroxidise, thioredoxin). These findings suggest that regular physical activity may have a protective effect against oxidative stress by increasing total antioxidant capacity, especially in postmenopausal women. Key PointsIt is important to consider daily physical activity status when evaluating antioxidant capacity.Sex differences affect the alteration of oxidative stress markers induced by daily physical activity.Regular physical activity may have a protective effect against oxidative stress by increasing total antioxidant capacity, especially in postmenopausal women. </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"571-8"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772604/pdf/jssm-12-571.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40257957","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":"Differential response of heat shock proteins to uphill and downhill exercise in heart, skeletal muscle, lung and kidney tissues.","authors":"Pablo C B Lollo,&nbsp;Carolina S Moura,&nbsp;Priscila N Morato,&nbsp;Jaime Amaya-Farfan","doi":"","DOIUrl":"","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Running on a horizontal plane is known to increase the concentration of the stress biomarker heat-shock protein (HSP), but no comparison of the expression of HSP70 has yet been established between the uphill (predominantly concentric) and downhill (predominantly eccentric) muscle contractions exercise. The objective of the study was to investigate the relationships between eccentric and concentric contractions on the HSP70 response of the lung, kidney, gastrocnemius, soleus and heart. Twenty-four male Wistar weanling rats were divided into four groups: non-exercised and three different grades of treadmill exercise groups: horizontal, uphill (+7%) and downhill (-7% of inclination). At the optimal time-point of six hours after the exercise, serum uric acid, creatine kinase (CK) and lactate dehydrogenase (LDH) were determined by standard methods and HSP70 by the Western blot analysis. HSP70 responds differently to different types of running. For kidney, heart, soleus and gastrocnemius, the HSP70 expression increased, 230, 180, 150 and 120% respectively of the reference (horizontal). When the contraction was concentric (uphill) and compared to downhill the increase in response of HSP70 was greater in 80% for kidney, 75% for gastrocnemius, 60% for soleus and 280% for the heart. Uric acid was about 50% higher (0.64 ± 0.03 mg·dL(-1)) in the uphill group as compared to the horizontal or downhill groups. Similarly, the activities of serum CK and LDH were both 100% greater for both the uphill and downhill groups as compared to the horizontal group (2383 ± 253 and 647.00 ± 73 U/L, respectively). The responsiveness of HSP70 appeared to be quite different depending on the type of tissue, suggesting that the impact of exercise was not restricted to the muscles, but extended to the kidney tissue. The uphill exercise increases HSP70 beyond the eccentric type and the horizontal running was a lower HSP70 responsive stimulus. Key PointsExercise can induce increases in HSP70 in the lung, kidney and heart, and in the soleus and gastrocnemius muscles, probably due to systemic alterations such as hypoxia, increase in temperature and the production of free radicals.Predominantly concentric contractions (running uphill), seem to be the most efficient way of increasing the HSP70 concentrations in the different tissues, followed by eccentric contraction (downhill) and lastly the concentric-eccentric cycle (horizontal).The energy demand, already known to influence HSP70, appears not to be the only factor responsible for the response of these proteins, considering that for the kidney and the soleus muscle, downhill running was more efficient in raising the HSP70 response than horizontal running.Future research should explore the mechanisms by which the eccentric, concentric and eccentric-concentric contractions are capable of influencing the responses of the heat shock proteins, opening possibilities for increasing the levels of these proteins in desirable situations, ","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"461-6"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772589/pdf/jssm-12-461.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40259106","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 acute vibration exercise on short-distance sprinting and reactive agility.","authors":"Darryl J Cochrane","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Vibration exercise (VbX) has been a popular modality to enhancing physical performance, where various training methods and techniques have been employed to improve immediate and long-term sprint performance. However, the use of acute side-alternating VbX on sprint and agility performance remains unclear. Eight female athletes preformed side-alternating vibration exercise (VbX) and control (no VbX) in a cross over randomised design that was conducted one week apart. After performing a warm-up, the athletes undertook maximal 5m sprints and maximal reactive agility sprints (RAT), this was followed by side-alternating VbX (26 Hz, 6mm) or control (no VbX). Immediately following the intervention, post-sprint tests and RAT were performed. There was a significant treatment effect but there was no time effect (pre vs. post) or interaction effect for sprint and RAT; however, side-alternating VbX did not compromise sprint and agility performance. Key PointsAcute VbX could be beneficial for the acceleration phase (1.5m) of a short-distance sprint.Acute VbX does not have positive influence on short-distance (3m & 5m) sprint performance.Acute VbX does not enhance reactive agility performance. </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"497-501"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772594/pdf/jssm-12-497.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40259111","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":"Psychological preparation of competitive judokas - a review.","authors":"Gal Ziv,&nbsp;Ronnie Lidor","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The purpose of this article was to review a series of studies (n = 18) on psychological preparation of competitive judokas. These studies were grouped according to the type of study performed - observational, experimental, and case studies. In addition, five psychological categories were identified: (a) imagery, (b) motivation, (c) stress, anxiety, and mood states, (d) eating attitudes and weight control, and (e) coach/athlete interactions. The main findings of this review are that (a) there is a lack of data regarding the use of imagery to improve judo performance; (b) goal involvement states of competitive judokas fluctuate and undergo abrupt changes during actual combat, according to the ecological constraints of the situation; (c) cortisol levels and somatic and cognitive anxiety tend to increase prior to and during a judo combat; (d) weight reduction programs that judokas undergo prior to a judo combat can lead to unpleasant moods, and cultural differences can lead to conflicting results; (e) psychological preparation plans should be tailored to each individual judoka, as there can be significant individual differences among the judokas. Based on the findings of our review, a number of research limitations and methodological concerns are discussed. Key PointsThis article reviews a series of studies (n = 18) examining psychological aspects of judokas who compete at the intermediate level, national team level, and international level, and who hold international titles.Weight reduction programs that judokas undergo prior to a judo combat can lead to unpleasant moods.Psychological preparation plans should be tailored to each individual judoka, as there can be significant individual differences among competitive judokas.An effort should be made to conduct experimental-designed studies in order to assess the effectiveness of psychological interventions in judo. </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"371-80"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772577/pdf/jssm-12-371.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40255699","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":"Interactive effects of visual and auditory intervention on physical performance and perceived effort.","authors":"Ju-Han Lin,&nbsp;Frank Jing-Horng Lu","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The purpose of this study was to investigate the effects of using different types of media on physical performance and perceived exertion. This study was divided into two parts. In Part 1, we examined the effects of different combination of audio and video interventions on physical performance and rating of perceived effort (RPE). We recruited 20 collegiate students who performed a 12-minute cycling task (where they were asked to bike as hard as possible) under 4 conditions (music, video, music and video, and control) in a randomized order. Results indicated participants in the 2 media groups (music & audio) reported a significantly lower score for RPE. In addition, there was also an effect of media type where participants in music condition perceived less effort on the cycling task compared to the video condition. Part 2 examined how music preference influenced physical performance, but used a running task (where they were asked to run as hard as possible), and by recruiting a much larger sample. Seventy-five students were assigned into 5 groups (high preference and high motivation, high preference and low motivation, low preference and low motivation, low preference and high motivation, and control) based on responses on the Brunel Music Rating Inventory (BMRI. Results showed that music preference, but not its motivational quality, had a significant effect on physical performance. Overall, these results show that listening to music, and in particular preferred music increases physical performance and reduces perceived effort. Key PointsAmong different sensory stimulations, music can enhance physical performance more strongly than video.In addition to the motivational level of the music, music preference can also influence the physical performance of aerobic exercise participants. </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"388-93"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772579/pdf/jssm-12-388.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40257172","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":"In vivo motion of femoral condyles during weight-bearing flexion after anterior cruciate ligament rupture using biplane radiography.","authors":"Kaining Chen,&nbsp;Li Yin,&nbsp;Liangjun Cheng,&nbsp;Chuan Li,&nbsp;Cheng Chen,&nbsp;Liu Yang","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The purpose of this study was to investigate in vivo three- dimensional tibiofemoral kinematics and femoral condylar motion in knees with anterior cruciate ligament (ACL) deficiency during a knee bend activity. Ten patients with unilateral ACL rupture were enrolled. Both the injured and contralateral normal knees were imaged using biplane radiography at extension and at 15°, 30°, 60°, 90°, and 120° of flexion. Bilateral knees were next scanned by computed tomography, from which bilateral three-dimensional knee models were created. The in vivo tibiofemoral motion at each flexion position was reproduced through image registration using the knee models and biplane radiographs. A joint coordinate system containing the geometric center axis of the femur was used to measure the tibiofemoral motion. In ACL deficiency, the lateral femoral condyle was located significantly more posteriorly at extension and at 15° (p < 0.05), whereas the medial condylar position was changed only slightly. This constituted greater posterior translation and external rotation of the femur relative to the tibia at extension and at 15° (p < 0.05). Furthermore, ACL deficiency led to a significantly reduced extent of posterior movement of the lateral condyle during flexion from 15° to 60° (p < 0.05). Coupled with an insignificant change in the motion of the medial condyle, the femur moved less posteriorly with reduced extent of external rotation during flexion from 15° to 60° in ACL deficiency (p < 0.05). The medial- lateral and proximal-distal translations of the medial and lateral condyles and the femoral adduction-abduction rotation were insignificantly changed after ACL deficiency. The results demonstrated that ACL deficiency primarily changed the anterior-posterior motion of the lateral condyle, producing not only posterior subluxation at low flexion positions but also reduced extent of posterior movement during flexion from 15° to 60°. Key PointsThree-dimensional tibiofemoral kinematics and femoral condylar motion in ACL-deficient knees during upright weight-bearing flexion were measured using biplane radiography with the geometric center axis.ACL deficiency caused posterior subluxation of the lateral condyle with excess external femoral rotation at early flexion positions.On flexion from 15° to 60°, the lateral condyle moved slightly posteriorly in ACL deficiency leading to reduced extent of external femoral rotation. </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"579-87"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772605/pdf/jssm-12-579.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40257958","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}