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Basic walker-assisted gait characteristics derived from forces and moments exerted on the walker's handles: results on normal subjects. Alwan Majd,Ledoux Alexandre,Wasson Glenn,Sheth Pradip,Huang Cunjun Medical engineering & physics This paper describes a method that passively assesses basic walker-assisted gait characteristics using only force-moment measurements from the walker's handles. The passively derived gait characteristics of 22 subjects were validated against motion capture gait analysis. The force-moment based heel initial contact detection algorithm have produced a high level of concordance with heel initial contacts detected by a human inspecting the heel marker data sets of the Vicon video capture system. The algorithm has demonstrated 97% sensitivity and 98% specificity with a narrow 95% confidence interval of +/-1% during all experiments, which included five navigational scenarios. Temporal error in detecting the instances of heel initial contacts were within 5.27+/-3.66% of the overall stride time obtained from Vicon when the subjects walked in a straight line, whereas the toe-off instance estimates were within 5.18+/-2.75% of the gait cycle. The errors in determining the duration of stride time, single support, and double support were within 5.86+/-2.49%, 5.24+/-2.29%, and 4.34+/-2.13% of the gait cycle respectively. The stride time estimated, using the method presented here, correlated well with stride time computations based on visual inspection of Vicon's data, Pearson correlation coefficient r=0.86 for straight line segments. However, absolute errors were too high to estimate the single and double support phases with acceptable accuracy. The potential application of the instrumented walker and the method presented here is longitudinal basic gait assessment that can be performed outside of the conventional gait labs. 10.1016/j.medengphy.2006.06.001
Force-velocity profile: imbalance determination and effect on lower limb ballistic performance. Samozino P,Edouard P,Sangnier S,Brughelli M,Gimenez P,Morin J-B International journal of sports medicine This study sought to lend experimental support to the theoretical influence of force-velocity (F-v) mechanical profile on jumping performance independently from the effect of maximal power output (P max ). 48 high-level athletes (soccer players, sprinters, rugby players) performed maximal squat jumps with additional loads from 0 to 100% of body mass. During each jump, mean force, velocity and power output were obtained using a simple computation method based on flight time, and then used to determine individual linear F-v relationships and P max values. Actual and optimal F-v profiles were computed for each subject to quantify mechanical F-v imbalance. A multiple regression analysis showed, with a high-adjustment quality (r²=0.931, P<0.001, SEE=0.015 m), significant contributions of P max , F-v imbalance and lower limb extension range (h PO ) to explain interindividual differences in jumping performance (P<0.001) with positive regression coefficients for P max and h PO and a negative one for F-v imbalance. This experimentally supports that ballistic performance depends, in addition to P max , on the F-v profile of lower limbs. This adds support to the actual existence of an individual optimal F-v profile that maximizes jumping performance, a F-v imbalance being associated to a lower performance. These results have potential strong applications in the field of strength and conditioning. 10.1055/s-0033-1354382
Timing of anterior cruciate ligament reconstruction and preoperative pain are important predictors for postoperative kinesiophobia. Theunissen W W E S,van der Steen M C,Liu W Y,Janssen R P A Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA PURPOSE:Fear of movement (kinesiophobia) is a major limiting factor in the return to pre-injury sport level after anterior cruciate ligament reconstruction (ACLR). The aim of this study was to gain insight into the prevalence of kinesiophobia pre-ACLR, 3 months post-ACLR and 12 months post-ACLR. Furthermore, the preoperative predictability of kinesiophobia at 3 months post-ACLR was addressed. METHODS:A retrospective study with data, which were prospectively collected as part of standard care, was conducted to evaluate patients who underwent ACLR between January 2017 and December 2018 in an orthopaedic outpatient clinic. Patient characteristics (age, sex, body mass index), injury-to-surgery time, preoperative pain level (KOOS pain subscale) and preoperative knee function (IKDC-2000) were used as potential predictor variables for kinesiophobia (TSK-17) at 3 months post-ACLR in linear regression analysis. RESULTS:The number of patients with a high level of kinesiophobia (TSK > 37) reduced from 92 patients (69.2%) preoperatively to 44 patients (43.1%) 3 months postoperatively and 36 patients (30.8%) 12 months postoperatively. The prediction model, based on a multivariable regression analysis, showed a positive correlation between four predictor variables (prolonged injury-to-surgery time, high preoperative pain level, male sex and low body mass index) and a high level of kinesiophobia at 3 months postoperatively (R = 0.384, p = 0.02). CONCLUSION:The prevalence of kinesiophobia decreases during postoperative rehabilitation, but high kinesiophobia is still present in a large portion of the patients after ACLR. Timing of reconstruction seems to be the strongest predictor for high kinesiophobia 3 months post-ACLR. This study is the first step in the development of a screening tool to detect patients with kinesiophobia after ACLR. Identifying patients preoperatively opens the possibility to treat patients and thereby potentially increase the return to pre-injury sport level rate after ACLR. LEVEL OF EVIDENCE:III. 10.1007/s00167-019-05838-z
High level of post-traumatic stress symptoms in patients with chronic neck pain is associated with poor mental health but does not moderate the outcome of a multimodal physiotherapy programme. Physiotherapy theory and practice INTRODUCTION:Chronic traumatic neck pain has a high prevalence of post-traumatic stress symptoms (PTSS). However, whether PTSS moderates treatment effects is unknown. This study investigated: 1) whether PTSS was associated with patient-reported outcomes and clinical test results at baseline; 2) whether PTSS moderated the effect of a multimodal physiotherapy intervention of exercise therapy and patient education; and 3) whether adherence to the intervention differed across PTSS groups. METHODS:Secondary data analysis from a randomized controlled trial on chronic neck pain with 12-month follow-up was conducted. Patients were divided into three groups (NT = non-traumatic, LT = traumatic low PTSS, HT = traumatic high PTSS) based on self-reported onset of pain and the Impact of Event Scale. The baseline data were used to analyze the association of PTSS with patient demographics and scores of physical and mental health-related quality of life, depression, neck-related disability, kinesiophobia, and clinical tests. Baseline, 4-month and 12-month follow-up data were analyzed to investigate possible moderating effects on outcomes. Data on adherence were collected at four months. RESULTS:115 participants were included (NT = 45; LT = 46; HT = 24). The HT group reported lower mental health scores and more depressive symptoms at baseline. PTSS did not significantly moderate the treatment effect on any outcomes. The HT group tended to have lower adherence to the multimodal physiotherapy intervention than the LT group. CONCLUSION:For patients with traumatic neck pain, high levels of PTSS are associated with poorer psychological outcomes but do not affect the outcomes of multimodal physiotherapy intervention. 10.1080/09593985.2022.2138730
More than a Metric: How Training Load is Used in Elite Sport for Athlete Management. West Stephen W,Clubb Jo,Torres-Ronda Lorena,Howells Daniel,Leng Edward,Vescovi Jason D,Carmody Sean,Posthumus Michael,Dalen-Lorentsen Torstein,Windt Johann International journal of sports medicine Training load monitoring is a core aspect of modern-day sport science practice. Collecting, cleaning, analysing, interpreting, and disseminating load data is usually undertaken with a view to improve player performance and/or manage injury risk. To target these outcomes, practitioners attempt to optimise load at different stages throughout the training process, like adjusting individual sessions, planning day-to-day, periodising the season, and managing athletes with a long-term view. With greater investment in training load monitoring comes greater expectations, as stakeholders count on practitioners to transform data into informed, meaningful decisions. In this editorial we highlight how training load monitoring has many potential applications and cannot be simply reduced to one metric and/or calculation. With experience across a variety of sporting backgrounds, this editorial details the challenges and contextual factors that must be considered when interpreting such data. It further demonstrates the need for those working with athletes to develop strong communication channels with all stakeholders in the decision-making process. Importantly, this editorial highlights the complexity associated with using training load for managing injury risk and explores the potential for framing training load with a performance and training progression mindset. 10.1055/a-1268-8791
The Preparticipation Physical Evaluation. MacDonald James,Schaefer Marie,Stumph Justin American family physician The preparticipation physical evaluation (PPE) is a common reason for young athletes to see a primary care physician. An annual PPE is required by most state high school athletic associations for participation in school-based sports, although there is limited evidence to support its effectiveness for detecting conditions that predispose athletes to injury or illness. In 2019, the American Academy of Pediatrics, with representatives from the American Academy of Family Physicians and other organizations, published updated PPE recommendations (PPE5). According to the guideline, the general goals of the PPE are determining general physical and psychological health; evaluating for life-threatening or disabling conditions, including risk of sudden cardiac arrest and other conditions that may predispose the athlete to illness or injury; and serving as an entry point into the health care system for those without a medical home or primary care physician. The guideline recommends that the evaluation take place in the physician's office rather than in a group setting. The PPE should include a structured physical examination that focuses on the cardiovascular, musculoskeletal, and neurologic systems. Screening for depression, anxiety disorders, and attention-deficit/hyperactivity disorder is also recommended. Clinicians should recognize any findings suggestive of the relative energy deficiency in sport syndrome. Additional consideration is required to address the needs and concerns of transgender athletes and athletes with physical and intellectual disabilities. Finally, guidelines have been published regarding return to play for athletes who have had COVID-19.
International Olympic Committee consensus statement: molecular basis of connective tissue and muscle injuries in sport. Ljungqvist Arne,Schwellnus Martin P,Bachl Norbert,Collins Malcolm,Cook J,Khan K M,Maffulli Nicola,Pitsiladis Y,Riley G,Golspink G,Venter D,Derman E W,Engebretsen L,Volpi P Clinics in sports medicine Tendon and ligament injures cause significant loss of performance in sport and decreased functional capacity in the workplace. Many of these injures remain difficult to treat, and many individuals have long-term pain and discomfort. Animal studies of growth factor and cell-based therapies have shown promising results, but these treatments also can be misused to enhance athletic performance. The International Olympic Committee (IOC) now has high-level scientific advisors who can advise the IOC as to the use and abuse of these technologies. 10.1016/j.csm.2007.10.007
Upcoming Paralympic summer games in Rio: what did the German medical team learn from the London Games? Kubosch Eva J,Kosel Jürgen,Steffen Kathrin,Konstantinidis Lukas,Kubosch David,Südkamp Norbert P,Hirschmüller Anja The Journal of sports medicine and physical fitness BACKGROUND:Musculoskeletal complaints are frequently diagnosed in Paralympic athletes. Despite the increased professionalism in Paralympic Sports, the documentation of injuries and other health complaints during high-level competition is sparse. With respect to the upcoming Paralympic Summer Games in Rio de Janeiro, the aim of this study was the analysis of all musculoskeletal complaints within the German Paralympic Athletes during the London 2012 Paralympic Games. METHODS:All musculoskeletal complaints (MSC) of the 150 German athletes seeking medical attention, hereby defined as "injury", were recorded during the in-competition period of the London Paralympics Games (22 days), regardless of their severity and consequences. Standardized documentation included the onset of symptoms, the medical diagnoses, the therapeutic measures taken as well as consecutive restrictions in training and competition. Incidence rates and localizations were analyzed by sports discipline. RESULTS:A total of 201 musculoskeletal complaints were recorded for 140 athletes (93.3%), corresponding to 1.4 musculoskeletal complaints per "injured" athlete. The incidence of musculoskeletal complaints in German athletes was 62.9±15.4/1000 athlete-days. High incidence rates (IR) were observed in wheelchair basketball (IR 72/1000 athlete-days, 1.6 injuries per athlete) and equestrian events (IR 72.7, 1.6). Musculoskeletal complaints were mainly located in the upper extremities (37.6%) and the spine (37.6%). The most frequent diagnoses were myalgia (N.=105, 52%). CONCLUSIONS:We noted a high rate of musculoskeletal complaints among German Paralympic athletes across sports and body parts, highlighting the need for prevention programs that focus on the upper extremities and spine. 10.23736/S0022-4707.16.06537-3
Strength Abilities in Men 50+ as an Effect of Long-Distance Run Training. Iwańska Dagmara,Mróz Anna,Wójcik Agnieszka,Witek Katarzyna,Czajkowska Anna,Kusztelak Małgorzata American journal of men's health The aim of this study was to evaluate the effect of long-term running training on muscle strength of men aged 50 and above. The study involved two groups of men aged 50 and above: physically active (E, = 34) and inactive (NE, = 20). Body composition was assessed with the electrical bioimpedance method. The isometric maximum voluntary contraction (MVC) was the main measurement. The value of muscle torque achieved by a group of synergists (operating in the given joint) during a short isometric contraction was evaluated. Ten groups of flexor and extensor muscles of the elbow, shoulder, hip, knee, and torso joints were measured. In addition, a 3 s measurement of grip strength of the right (F) and left (F) hand was taken using a hand dynamometer. The obtained values enabled to calculate the symmetry index (SI). Men who had been running regularly were characterized by a significantly lower strength level ( < .05). Results in the NE group were determined to a great extent by significantly different body weights ( < .001) and a significantly higher body fat mass (FAT) content ( < .001). SI was statistically higher in the reference group ( < .05). Long-distance run training reduces FAT while maintaining a high level of muscle strength. These studies indirectly confirm the effect of strengthening slow-twitch motor units in men aged 50 (Doherty & Brown 1993; Kanda & Hashizume 1989). In addition, stimulating the body through physical effort helps it also to maintain a high level of strength symmetry, which is a preventive factor in reducing the number of injuries. 10.1177/1557988319859108
Perceptions of football players regarding injury risk factors and prevention strategies. Zech Astrid,Wellmann Kai PloS one Current approaches regarding injury prevention focus on the transfer of evidence into daily practice. One promising approach is to influence attitudes and beliefs of players. The objective of this study was to record player's perceptions on injury prevention. A survey was performed among players of one German high-level football (soccer) club. 139 professional and youth players between age 13 and 35 years completed a standardized questionnaire (response rate = 98%). It included categories with (1) history of lower extremity injuries, (2) perceptions regarding risk factors and (3) regularly used prevention strategies. The majority of players (84.2%) had a previous injury. 47.5% of respondents believe that contact with other players is a risk factor, followed by fatigue (38.1%) and environmental factors (25.9%). The relevance of previous injuries as a risk factor is differently perceived between injured (25%) and uninjured players (0.0%). Nearly all players (91.5%) perform stretching to prevent injuries, followed by neuromuscular warm up exercises (54.0%). Taping is used by 40.2% of previously injured players and 13.6% of players without a history of injuries. In conclusion, the perception of risk factors and performed preventive strategies are inconsistent with scientific evidence. Future transfer strategies should incorporate the players beliefs and attitudes. 10.1371/journal.pone.0176829
More data needed on injury risk among young elite athletes. Steffen Kathrin,Engebretsen Lars British journal of sports medicine Injuries can counter the beneficial effects of sports participation at a young age if a child or adolescent is unable to continue to participate because of residual effects of injury. Independent of activity level, injuries represent a considerable problem for the athlete and can result in an increased potential for future disability and inactivity. Injuries are also referred to as one of the major reasons for athletes to drop out of sports. Systematic injury registrations at the youth and adolescent level have been performed in recreational sports to gain knowledge on injury risk, as well as on the most common and most severe sport specific injuries. However, information on injury risk of the young athlete competing in high level sports seems less available or unknown. This paper reviews the current knowledge on injury risk of the youth and adolescent elite athlete participating in sports presented in the Youth Olympic Games 2010. Apart from football, little is known on injury epidemiology among young elite athletes. Systematic injury surveillance of this highly competitive population is needed to monitor injuries, identify high risk sports, and ensure new knowledge on injury trends, which can form the basis for further research on injury risk factors, mechanisms, and in the final step, on injury prevention. 10.1136/bjsm.2010.073833
Sports injuries related to flexibility, posture, acceleration, clinical defects, and previous injury, in high-level players of body contact sports. Watson A W International journal of sports medicine One-hundred-and-two high-level players of the field-games soccer, Gaelic football and hurling began a two-year investigation into the intrinsic causes of sports-injuries; 86 completed the study. During the first year all injuries, and the time affected by injury, were recorded. The subjects then underwent flexibility tests, an accurate photogrammetric assessment of posture, measures of speed and acceleration, and a clinical assessment of anatomical and physiological factors thought to be associated with the risk of sports injury. Time affected by injury was then recorded for a further 12-month period. Stepwise multiple-regression analysis revealed that the number of days of injury during the second 12-month period could be predicted from (1) the days of injury during the first 12-month period, (2) posture, (3) acceleration over 10m from a standing start, and (4) the number of musculo-skeletal clinical defects. Flexibility scores were not found to be significant predictors of injury. It is suggested that injury prevention programmes should concentrate on improving posture and the rehabilitation from previous injury rather than flexibility; and that research should be undertaken into the effectiveness of such interventions. 10.1055/s-2001-16383
Muscle Activation in the Main Muscle Groups of the Lower Limbs in High-Level Dancesport Athletes. Liébana Encarnación,Monleón Cristina,Morales Raquel,Pablos Carlos,Moratal Consuelo,Blasco Esther Medical problems of performing artists Dancers are subjected to high-intensity workouts when they practice dancesport, and according to the literature, they are prone to injury, primarily of the lower limbs. The purpose of this study was to determine whether differences exist in relative activation amplitudes for dancers involved in dancesport due to muscle, gender, and type of dance. Measurements were carried out using surface electromyography equipment during the choreography of a performance in the following leg muscles: rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius medialis. Eight couples of active dancesport athletes (aged 20.50±2.75 yrs) were analyzed. Significant gender differences were found in rumba in the tibialis anterior (p≤0.05) and gastrocnemius medialis (p≤0.05). Based on the different activations, it is possible to establish possible mechanisms of injury, as well as tools for preventing injuries and improving sports performance. 10.21091/mppa.2018.4034