Active control stabilization of pelvic position in the transverse plane: An evaluation of soccer players' performance

ObjectivesTo describe the capability of soccer players to stabilize pelvic position actively in the transverse plane; and, to evaluate the influence of lower limb dominance, length of exposure to soccer practice, and field position on pelvic stabilization capability.DesignCross-sectional.ParticipantsSixty-eight soccer players from under-15 (U-15) and professional categories.Main outcome measuresMagnitude and asymmetry of pelvic tilt in the transverse plane, evaluated using the bridge test with unilateral knee extension.ResultsThe magnitude of pelvic tilt did not differ between dominant and non-dominant sides, suggesting absence of relative asymmetry. However, there was difference between the sides of greater and lesser magnitude of pelvic tilt, indicating presence of absolute asymmetry. Players with shorter length of exposure to soccer practice (U-15 group) had greater pelvic tilt than players with longer length of exposure (professional group). There was no association of field position with the magnitude and asymmetry of pelvic tilt.ConclusionSoccer players showed asymmetry in pelvic stabilization capability that was unrelated to lower limb dominance or field position. Athletes with longer length of exposure to soccer practice present better capability to stabilize the pelvis in the transverse plane than those with shorter length of exposure to soccer practice.     

Pain perception in athletes compared to normally active controls: a systematic review with meta-analysis

This study systematically reviewed differences in pain perception between athletes and normally active controls. We screened MEDLINE, Sport-Discus, EMBASE, Web of Science, PsycINFO, PSYNDEX, and the citations of original studies and systematic reviews. All studies on experimentally induced pain that compared pain perception between athletes and normally active controls were eligible. The main outcome measures were pain tolerance and pain threshold. Effects are described as standardized mean differences and were pooled using random-effects models. Fifteen studies including 899 subjects met the inclusion criteria. Twelve of these studies assessed pain tolerance, and 9 studies examined pain threshold. A meta-analysis of these studies revealed that athletes possessed higher pain tolerance compared to normally active controls (effect size calculated as Hedges' g=0.87, 95% confidence interval [CI(95)] 0.53-1.21; P<0.00001), whereas available data on pain threshold were less uniform (Hedges' g=0.69, CI(95) 0.16-1.21; P=0.01). After exclusion of studies with high risk of bias, differences between groups in pain threshold were not significant any longer. Our data suggest that regular physical activity is associated with specific alterations in pain perception. Psychological and biological factors that may be responsible for these alterations are discussed.     

Dynamic component of sports is an important determinant factor of heart rate recovery

Objective

It is usually suggested that life expectancy of top athletes especially in endurance sports is longer than that of sedentary people. On the other hand, heart rate recovery (HRR) after exercise is an independent risk factor for cardiovascular disease and mortality, but differences in HRR between various top athletes are unclear. We examined HRR in various top athletes to clarify a role of HRR that may affect their life expectancy.

Methods

HRR was defined as the difference between the heart rate at peak exercise and that at 2 min after the finish of exercise using symptom-limited maximal graded bicycle ergometer exercise testing. The relationships between HRR with the grade of static and dynamic component of classification of sports, age, and body mass index (BMI) were estimated.

Subjects

The subjects were 720 male athletes participating in the National Sports Festival Japan in 2005–2008 and age-matched 28 sedentary controls.

Results

HRR was significantly correlated (p < 0.0001) with the higher grade of dynamic component of sports, younger age, and lower BMI in both univariate and multivariate analysis.

Conclusions

HRR of top athletes is predicted by increased dynamic component of sports, younger age, and lower BMI.     

广州市青少年运动员焦虑抑郁情绪相关因素分析

目的 探讨青少年运动员焦虑抑郁的危险因素和保护性因素.方法 随机整群抽取广州市两所中等体育运动学校的520名青少年运动员学生,利用综合性医院焦虑抑郁量表(HADS)对焦虑和抑郁情绪程度进行评估,用多元逐步回归分析焦虑抑郁相关影响因素.结果 438名青少年运动员中处于高危焦虑的有30名(6.9%),处于高危抑郁的有76名(17.4%);其中来自老师和教练压力较大(sβ=5.372)、年龄大于17岁(sβ=4.365)、母亲受教育水平中等(sβ=3.153)是焦虑的保护性因素,而低质量(sβ=2.482)则是焦虑的危险性因素;母亲的受教育水平中等(sβ=6.764)、来自老师和教练压力较大(sβ=4.167)是抑郁的保护性因素,而年龄在15～16岁之间(sβ=3.367)、有家族性慢性病史(sβ=2.765)、所受总的支持较差(sβ=4.365)是抑郁的危险性因素.结论 青少年运动员的焦虑抑郁情绪高发,影响因素众多,正确识别这些因素可以预防青少年运动员相关精神疾病的发生.     

Seasonal training and heart rate and blood pressure variabilities in young swimmers

To evaluate if changes in athletes’ physical fitness due to seasonal training are associated with changes in cardiovascular autonomic control, nine swimmers (three males and six females; aged 14–18 years) were evaluated before and after 5 months of training and competitions. Maximal oxygen consumption and ventilatory threshold were determined during a maximal test; heart rate (HR) and blood pressure (BP) variabilities’ power spectra were calculated at rest (supine and sitting positions) and in the recovery of two exercises at 25 and 80% pre-training At the end of the season: (a) and ventilatory threshold increased respectively by 12 and 34% (P<0.05); (b) at rest, HR decreased by 9 b min⁻¹ in both body positions, whereas BP decreased in supine position only by 17%. No change in low frequency (LF, 0.04–0.15 Hz) and high frequency (HF, 0.15–1.5 Hz) normalized powers and in LF/HF ratio of HR variability and in LF power of systolic BP variability was observed. In contrast, a significant increase in HF α-index (about 12 ms mmHg⁻¹) was found; (c) during recovery no change in any parameter was observed. Seasonal training improved exercise capacity and decreased resting cardiovascular parameters, but did not modify vagal and sympathetic spectral markers. The increase in α-index observed at rest after the season and expression of augmented baroreflex sensibility indicated however that HR vagal control could have been enhanced by seasonal training. These findings suggested that autonomic system might have played a role in short-term adaptation to training.     

A history of sport-related concussion on event-related brain potential correlates of cognition

Over the past decade, a growing body of research has detailed persistent changes to neuroelectric indices of cognition in amateur and professional athletes with a concussion history. Here, we review the relevant neuroelectric findings on this relationship while considering the duration from the last concussive event. Collectively, the findings support a negative relation of concussive injury to neuroelectric indices of brain health and cognition in the presence of normal clinical findings. The results suggest that event-related brain potentials are especially well-suited for identifying aspects of cognition that remain dysfunctional for an extended period of time, which are otherwise unidentified using standard neuropsychological tests. Such findings also suggest the need for additional research to fully elucidate the extent to which concussive injuries negatively impact brain health and cognition.     

The slope of the oxygen pulse curve does not depend on the maximal heart rate in elite soccer players

INTRODUCTION:

It is unknown whether an extremely high heart rate can affect oxygen pulse profile during progressive maximal exercise in healthy subjects.

OBJECTIVE:

Our aim was to compare relative oxygen pulse (adjusted for body weight) curves in athletes at their maximal heart rate during treadmill cardiopulmonary exercise testing.

METHODS:

A total of 180 elite soccer players were categorized in quartiles according to their maximum heart rate values (n  =  45). Oxygen consumption, maximum heart rate and relative oxygen pulse curves in the extreme quartiles, Q1 and Q4, were compared at intervals corresponding to 10% of the total duration of a cardiopulmonary exercise testing.

RESULTS:

Oxygen consumption was similar among all subjects during cardiopulmonary exercise testing; however subjects in Q1 started to exhibit lower maximum heart rate values when 20% of the test was complete. Conversely, the relative oxygen pulse was higher in this group when cardiopulmonary exercise testing was 40% complete (p<.01). Although the slopes of the lines were similar (p = .25), the regression intercepts differed (p<.01) between Q1 and Q4. During the last two minutes of testing, a flat or decreasing oxygen pulse was identified in 20% of the soccer players, and this trend was similar between subjects in Q1 and Q4.

CONCLUSION:

Relative oxygen pulse curve slopes, which serve as an indirect and non-invasive surrogate for stroke volume, suggest that the stroke volume is similar in young and aerobically fit subjects regardless of the maximum heart rate reached.     

山东省6所高校大学生田径运动员运动损伤调查

目的方法本文通过问卷调查等方法,研究了山东大学生田径运动员运动损伤的情况。结果结果表明山东大学生田径运动员的运动损伤与田径不同专项的特点有密切的关系,并且产生运动损伤的原因是复杂多样的,应针对产生运动损伤的原因开展预防工作结论结合运动损伤原因,提出了相关有效的预防措施,以期为提高教学质量提供科学的、有效的指导和理论依据。     

Syncope in the athlete – Minor changes,major diagnosis!

We report the case of a 17-year-old athlete who resorted to the emergency department for palpitations and dizziness while exercising. He mentioned two exercise-associated episodes of syncope in the last six months. He was tachycardic and hypotensive. The electrocardiogram showed regular wide complex tachycardia, left bundle branch block morphology with superior axis restored to sinus rhythm after electrical cardioversion. In sinus rhythm, it showed T-wave inversion in V1–V5. Transthoracic echocardiography revealed mild dilation and dysfunction of the right ventricle (RV) with global hypocontractility. Cardiac magnetic resonance (CMR) revealed a RV end diastolic volume indexed to body surface area of 180 ml/m², global hypokinesia and RV dyssynchrony, subepicardial late enhancement in the distal septum and in the middle segment of the inferoseptal wall. The patient underwent a genetic study which showed a mutation in the gene that encodes the desmocolin-2 protein (DSC-2), which is involved in the pathogenesis of arrhythmogenic right ventricular cardiomyopathy (ARVC). According to the modified Task Force Criteria for this diagnosis, the patient presented four major criteria for ARVC. Thus, a subcutaneous cardioverter was implanted, and the patient was followed up at the cardiology department.Arrhythmogenic right ventricular cardiomyopathy diagnosis is based on structural, functional, electrophysiological and genetic criteria reflecting underlying histological changes. This case depicts the essential characteristics for disease recognition.     

Therapeutic ultrasound related pain threshold in elite track & field athletes with tibial bone stress injuries

ObjectiveTibial stress injuries are challenging in terms of early diagnosis, management strategy, and safe return-to-play. In the present study, pain production associated with the application of therapeutic ultrasound (TUS) was used as a primary diagnostic tool to assess tibial bone stress injuries, and the sensitivity of this procedure was compared with Magnetic Resonance Imaging (MRI).Subject and methodsThe study was designed as a retrospective analysis of prospectively collected data on tibial bone stress injuries in elite Track and field athletes attending the National Track and Field Athletics Centre in Thessaloniki, Greece, in the period 1995–2007. All patients underwent evaluation by TUS, and the sensitivity of the procedure was compared with MRI.ResultsFour of 29 athletes showed a positive TUS examination for stress injury while MRI showed normal findings. Additionally, 5 athletes evidenced MRI findings typical of a tibial bone stress injury, while TUS evaluation was negative. Using MRI as the standard, TUS displayed a sensitivity of 79.2%.ConclusionTherapeutic ultrasound is a reproducible modality with satisfactory reliability and sensitivity related to MRI, and could represent a useful tool for clinicians to primarily assess suspected tibial bone stress injuries in high qualification Track and Field athletes.