Effect of N-acetylcysteine on markers of skeletal muscle injury after fatiguing contractile activity

The effects of N-Acetylcysteine (NAC), an unspecific antioxidant, on fatiguing contractile activity-induced injury were investigated. Twenty-four male Wistar rats were randomly assigned to two groups. The placebo group (N=12) received one injection of phosphate buffer (PBS) 1 h prior to contractile activity induced by electrical stimulation. The NAC group (NAC; N=12) received electrical stimulation for the same time period and NAC (500 mg/kg, i.p.) dissolved in PBS 1 h prior to electrical stimulation. The contralateral hindlimb was used as a control, except in the analysis of plasma enzyme activities, when a control group (rats placebo group not electrically stimulated and not treated) was included. The following parameters were measured: tetanic force, muscle fatigue, plasma activities of creatine kinase (CK) and lactate dehydrogenase (LDH), changes in muscle vascular permeability using Evans blue dye (EBD), muscle content of reactive oxygen species (ROS) and thiobarbituric acid-reactive substances (TBARS) and myeloperoxidase (MPO) activity. Muscle fatigue was delayed and tetanic force was preserved in NAC-treated rats. NAC treatment decreased plasma CK and LDH activities. The content of muscle-derived ROS, TBARS, EBD and MPO activity in both gastrocnemius and soleus muscles were also decreased by NAC pre-treatment. Thus, NAC has a protective effect against injury induced by fatiguing contractile activity in skeletal muscle.

Infrared (810 nm) Low-Level Laser Therapy in Experimental Model of Strain-Induced Skeletal Muscle Injury in Rats: Effects on Functional Outcomes

Muscle strains are among the most prevalent causes for athletes absence from sport activities. Low-level laser therapy (LLLT) has recently emerged as a potential contender to nonsteroidal anti-inflammatory drugs in muscle strain treatment. In this work we investigated effects of LLLT and diclofenac on functional outcomes in the acute stage after muscle strain injury in rats. Muscle strain was induced by overloading the tibialis anterior muscle of rats during anesthesia. The injured groups received either no treatment, or a single treatment with diclofenac 30 min prior to injury, or LLLT (810 nm, 100 mW) with doses of 1, 3, 6 or 9 J, at 1 h after injury. Functional outcome measures included a walking index and assessment of electrically induced muscle performance. All treatments (except 9 J LLLT) significantly improved the walking index 12 h postinjury compared with the untreated group. The 3 J group also showed a significantly better walking index than the drug group. All treatments significantly improved muscle performance at 6 and 12 h. LLLT dose of 3 J was as effective as the pharmacological agent in improving functional outcomes in the early phase after a muscle strain injury in rats.

Regular and moderate exercise before experimental sepsis reduces the risk of lung and distal organ injury

de Araujo CC, Silva JD, Samary CS, Guimaraes IH, Marques PS, Oliveira GP, do Carmo LGRR, Goldenberg RC, Bakker-Abreu I, Diaz BL, Rocha NN, Capelozzi VL, Pelosi P, Rocco PRM. Regular and moderate exercise before experimental sepsis reduces the risk of lung and distal organ injury. J Appl Physiol 112: 1206-1214, 2012. First published January 19, 2012; doi:10.1152/japplphysiol.01061.2011.-Physical activity modulates inflammation and immune response in both normal and pathologic conditions. We investigated whether regular and moderate exercise before the induction of experimental sepsis reduces the risk of lung and distal organ injury and survival. One hundred twenty-four BALB/c mice were randomly assigned to two groups: sedentary (S) and trained (T). Animals in T group ran on a motorized treadmill, at moderate intensity, 5% grade, 30 min/day, 3 times a week for 8 wk. Cardiac adaptation to exercise was evaluated using echocardiography. Systolic volume and left ventricular mass were increased in T compared with S group. Both T and S groups were further randomized either to sepsis induced by cecal ligation and puncture surgery (CLP) or sham operation (control). After 24 h, lung mechanics and histology, the degree of cell apoptosis in lung, heart, kidney, liver, and small intestine villi, and interleukin (IL)-6, KC (IL-8 murine functional homolog), IL-1 beta, IL-10, and number of cells in bronchoalveolar lavage (BALF) and peritoneal lavage (PLF) fluids as well as plasma were measured. In CLP, T compared with S groups showed: 1) improvement in survival; 2) reduced lung static elastance, alveolar collapse, collagen and elastic fiber content, number of neutrophils in BALF, PLF, and plasma, as well as lung and distal organ cell apoptosis; and 3) increased IL-10 in BALF and plasma, with reduced IL-6, KC, and IL-1 beta in PLF. In conclusion, regular and moderate exercise before the induction of sepsis reduced the risk of lung and distal organ damage, thus increasing survival.

Women sport injuries: a retrospective study of elite windsurfers

This study was designed to identify the injuries of professional women windsurfers, from their anatomical location, type of sport, context when they occurred, type of injury, the time of inactivity as a result of the same, the type of health care received and the relationship between the number of injuries and the position in the final classification of professional windsurfing competitions. We gave a retrospective questionnaire to 18 women elite windsurfers, who took part in the World Cup competition held in Fuerteventura (2008). Women are injured more frequently during training than competition (77.8%; p<0.05 vs. 20.5%). Women suffer leg injuries more than men (83.3%; p<0.05 vs. 14.3%) in freestyle. Serious injuries were more frequent for women (66.7%; p<0.05 vs. 28.2%) and the time of inactivity due to the injury was shorter for women (50%; p<0.05 vs. 20.5%). These results indicate that female windsurfers are more liable to suffer injuries, generally serious, during training sessions. Freestyle involves a greater risk of leg injuries for women. The knee is the area where most injuries occur, both for men and women, followed by the legs.

Incidence injury analysis on rowers in the Spanish Mediterranean fixed bench championship 2012

The standardized assessment of sports injuries provides important epidemiological information and instructions to prevent them. The aim of this study was to determine if the pattern detrimental impact on fixed seat rowing agreed with the literature review of the Olympic rowing modality. A retrospective questionnaire was administer to 79 male rowers, with an age mean of 27.66 ± 7.15, belonging to the male in the senior category VIII Rowing Spanish Mediterranean Bank Fixed Championship that took place in Torrevieja during the 25th, 26th and 27th of May. The anatomical regions that were damage the most were the ankle (15.4%) and lower back (13.2%). These injuries have occurred with higher incidence in training (55.1%) as the most recidivist injury, the ankle, which has occurred for 73% of the time during this moment. The most common injury is the overuse (44.2%) and the most repeated diagnosis was sprain (23.1%).

Dizziness and unsteadiness following whiplash injury: Characteristic features and relationship with cervical joint position error

Dizziness and/or unsteadiness are common symptoms of chronic whiplash-associated disorders. This study aimed to report the characteristics of these symptoms and determine whether there was any relationship to cervical joint position error. Joint position error, the accuracy to return to the natural head posture following extension and rotation, was measured in 102 subjects with persistent whiplash-associated disorder and 44 control subjects. Whiplash subjects completed a neck pain index and answered questions about the characteristics of dizziness. The results indicated that subjects with whiplash-associated disorders had significantly greater joint position errors than control subjects. Within the whiplash group, those with dizziness had greater joint position errors than those without dizziness following rotation (rotation (R) 4.5degrees (0.3) vs 2.9degrees (0.4); rotation (L) 3.9degrees (0.3) vs 2.8degrees (0.4) respectively) and a higher neck pain index (55.3% (1.4) vs 43.1% (1.8)). Characteristics of the dizziness were consistent for those reported for a cervical cause but no characteristics could predict the magnitude of joint position error. Cervical mechanoreceptor dysfunction is a likely cause of dizziness in whiplash-associated disorder.

Protective Eyewear Promotion: Applying Principles of Behaviour Change in the Design of a Squash Injury Prevention Programme

Eye injuries in squash have the potential to be severe. Although these injuries can be prevented through the use of protective eyewear, few players wear such eyewear. The aim of this paper is, to outline the behavioural principles guiding the design of a squash eyewear promotion initiative, the Protective Eyewear Promotion (PEP). Ecological principles of behaviour change were used to provide a comprehensive perspective on intrapersonal factors, policies and physical environmental influences of protective eyewear use. Results of baseline player surveys and venue manager inter-views were used to provide relevant and specific intervention content. At baseline, protective eyewear was not found to be readily available, and players' behaviours, knowledge and attitudes did not favour its use. The main components of PEP involved informing and educating both players and squash venue operators of the risk of eye injury and of appropriate protective eyewear, as well as assisting with the availability of the eyewear and offering incentives for players to use it. A structural strength of PEP was the strong collaborative links with the researchers of different disciplines, the squash governing body, eyewear manufacturers, squash venue personnel, as well as players. Attempts were made within the project structure to make provision for the future dissemination and sustainability of more widespread eye injury prevention measures in the sport of squash.

Validity of accelerometry for measurement of activity in people with brain injury

Purpose: To evaluate the validity of a uniaxial accelerometer (MTI Actigraph) for measuring physical activity in people with acquired brain injury (ABI) using portable indirect calorimetry (Cosmed K4b(2)) as a criterion measure. Methods: Fourteen people with ABI and related gait pattern impairment (age 32 +/- 8 yr) wore an MTI Actigraph that measured activity (counts(.)min-(1)) and a Cosmed K4b(2) that measured oxygen consumption (mL(.)kg(-1.)min(-1)) during four activities: quiet sitting (QS) and comfortable paced (CP), brisk paced (BP), and fast paced (FP) walking. MET levels were predicted from Actigraph counts using a published equation and compared with Cosmed measures. Predicted METs for each of the 56 activity bouts (14 participants X 4 bouts) were classified (light, moderate, vigorous, or very vigorous intensity) and compared with Cosmed-based classifications. Results: Repeated-measures ANOVA indicated that walking condition intensities were significantly different (P < 0.05) and the Actigraph detected the differences. Overall correlation between measured and predicted METs was positive, moderate, and significant (r = 0.74). Mean predicted METs were not significantly different from measured for CP and BP, but for FP walking, predicted METs were significantly less than measured (P < 0.05). The Actigraph correctly classified intensity for 76.8% of all activity bouts and 91.5% of light- and moderate-intensity bouts. Conclusions: Actigraph counts provide a valid index of activity across the intensities investigated in this study. For light to moderate activity, Actigraph-based estimates of METs are acceptable for group-level analysis and are a valid means of classifying activity intensity. The Actigraph significantly underestimated higher intensity activity, although, in practice, this limitation will have minimal impact on activity measurement of most community-dwelling people with ABI.

Unprotected eyes in squash: not seeing the risk of injury

The use of appropriate eyewear in squash can protect the eyes against injury. However, few adult squash players adequately protect their eyes against potential severe injuries. We describe the characteristics of non-users of protective eyewear and examine predictors of appropriate eyewear use. Self-report surveys of adult players were conducted in metropolitan Melbourne, Australia. Information on players' knowledge, behaviours and attitudes associated with protective eyewear use was collected, in addition to player demographic data. Appropriate eyewear was defined as Standards-approved polycarbonate lens eyewear. The majority 92.2% of players did not adequately protect their eyes while playing squash. Significant predictors of reported eyewear use were: previous eye injury; playing squash on average more than 2 hr per wk; having played for more than 20 y; and having more favourable attitudes towards eye safety in squash. The significant predictors of appropriate eyewear use were: being female; previous eye injury; playing squash on average more than 2 hr per week; and having more favourable attitudes towards eye safety in squash. Understanding the characteristics of both users and non-users of appropriate eye protection in squash is essential for informing future prevention strategies.

MODERN SPORT COACHING AND THE LAW: IMPLICATIONS FOR COACH EDUCATION

Introduction
The intersection between the law of negligence and sport coaching in the UK is a developing area (Partington, 2014; Kevan, 2005). Crucially, since the law of negligence may be regarded as generally similar everywhere (Magnus, 2006), with the predominance of volunteer coaches in the UK reflective of the majority of countries in the world (Duffy et al., 2011), a detailed scrutiny of this relationship from the perspective of the coach uncovers important implications for coach education beyond this jurisdiction.  
Argumentation
Fulfilment of the legal duty of discharging reasonable care may be regarded as consistent with the ethical obligation not to expose athletes to unreasonable risks of injury (Mitten, 2013). More specifically, any ‘profession’ requiring ‘special skill or competence’ (Bolam v Friern Hospital Management Committee [1957] 1 WLR 582), including the coaching of sport (e.g., Davenport v Farrow [2010] EWHC 550), requires a higher standard of care to be displayed than would be expected of the ordinary reasonable person (Lunney & Oliphant, 2013; Jones & Dugdale, 2010). For instance, volunteer coaches with no formal qualifications (e.g., Fowles v Bedfordshire County Council [1996] ELR 51) would be judged by this benchmark of professional liability (Powell & Stewart, 2012). Further, as the principles of coaching are constantly assessed and revised (Cassidy et al., 2009; Taylor & Garratt, 2010), so too is the legal standard of care required of coaches (Powell & Stewart, 2012). Problematically, ethical concerns may include coaches being unwilling to increase knowledge, abusive treatment of players and incompetence/inexperience (Haney et al., 1998). These factors accentuate coaches’ exposure to civil liability.
Implications
It is imperative that coaches have an awareness of this emerging intersection and develop a ‘proactive risk assessment lens’ (Hartley, 2010). In addition to supporting the professionalisation of sport coaching, coach education/CPD focused on the legal and ethical aspects of coaching (Duffy et al., 2011; Telfer, 2010; Haney et al., 1998) would enhance the safety and welfare of performers, safeguard coaches from litigation risk, and potentially improve all levels of coaching (Partington, 2014). Interestingly, there is evidence to suggest a demand from coaches for more training on health and safety issues, including risk management and (ir)responsible coaching (Stirling et al., 2012). Accordingly, critical examination of the issue of negligent coaching would inform coach education by: enabling the modelling and sharing of best practice; unpacking important ethical concerns; and, further informing the classification of coaching as a ‘profession’.

A review of risk factors for hamstring injury in soccer: a biomechanical approach

The aim has been to review the literature about the risk factors of hamstring injury in soccer from a biomechanical point of view. METHODOLOGY. Data bases of bibliography references were Medline, Scopus and SportDiscuss. RESULTS AND DISCUSSION. Many prospective studies have shown that the previous injury is the greatest risk factor of sustaining the injury. However the primary causes of the injury are unclear in soccer. A lack of hamstring flexibility has been one of the main injury risk factors with controversies on the results. Imbalance of isokinetic force is a risk factor but electrical coactivation of all muscles participating during knee flexion and extension are unknown in football. While the importance of lumbopelvic-hamstrings muscles synchronization during running seems to be crucial for understanding the risk of injury, no research has been developed in this topic in football. CONCLUSIONS. More research using new data recording procedures as Dynamic Scanners, Surface EMG, Inverse Dynamic Analysis are needed. The analysis of more specific movements as running, kicking or jumping is clearly required. Managers, coaches, physical trainers, physiotherapists, sport physicians and researchers should work together in order to improve the injury prevention and rehabilitation programs of football players. Key Words: sports biomechanics, soccer, hamstring injury, risk factors