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Journal: Journal of athletic training


  To test a helmetless-tackling behavioral intervention for reducing head impacts in National Collegiate Athletic Association Division I football players.

Concepts: College football, American football


 Identification of strategies to prevent spinal injury, optimize rehabilitation, and enhance performance is a priority for practitioners. Different exercises produce different effects on neuromuscular performance. Clarity of the purpose of a prescribed exercise is central to a successful outcome. Spinal exercises need to be classified according to the objective of the exercise and planned physical outcome.

Concepts: Physical exercise, Exercise, Sports training


Weakness or decreased activation of the hip abductors and external rotators has been associated with lower extremity injury, especially in females. Resisted side stepping is commonly used to address hip weakness. Whereas multiple variations of this exercise are used clinically, few data exist regarding which variations to select.


After knee-joint injury, pain, effusion, and mechanoreceptor damage alter afferent signaling, which can result in quadriceps inhibition and subsequent weakness. The individual contributions of each factor to inhibition remain unclear due to confounding knee-joint injuries and indirect experimental models.


Overtraining syndrome (OTS) and related conditions cause decreased training performance and fatigue through an imbalance among training volume, nutrition, and recovery time. No definitive biochemical markers of OTS currently exist.


Context :  After an intense bout of exercise, foam rolling is thought to alleviate muscle fatigue and soreness (ie, delayed-onset muscle soreness [DOMS]) and improve muscular performance; however, no empirical evidence confirms this belief. Potentially, foam rolling may be an effective therapeutic modality to reduce DOMS while enhancing the recovery of muscular performance. Objective :  To examine the effects of foam rolling as a recovery tool after an intense exercise protocol through assessment of pressure-pain threshold, sprint time, change-of-direction speed, power, and dynamic strength-endurance. Design :  Controlled laboratory study. Setting :  University laboratory. Patients or Other Participants :  A total of 8 healthy, physically active males (age = 22.1 ± 2.5 years, height = 177.0 ± 7.5 cm, mass = 88.4 ± 11.4 kg) participated. Intervention(s) :  Participants performed 2 conditions, separated by 4 weeks, involving 10 sets of 10 repetitions of back squats at 60% of their 1-repetition maximum , followed by either no foam rolling or 20 minutes of foam rolling immediately, 24, and 48 hours postexercise. Main Outcome Measure(s) :  Pressure-pain threshold, sprint speed (30-m sprint time), power (broad-jump distance), change-of-direction speed (T-test), and dynamic strength-endurance. Results :  Foam rolling substantially improved quadriceps muscle tenderness by a moderate to large amount in the days after fatigue (Cohen d range, 0.59 to 0.84). Substantial effects ranged from small to large in sprint time (Cohen d range, 0.68 to 0.77), power (Cohen d range, 0.48 to 0.87), and dynamic strength-endurance (Cohen d = 0.54). Conclusions :  Foam rolling effectively reduced DOMS and associated decrements in most dynamic performance measures.

Concepts: Exercise physiology


The ratio of clinicians to patients has been associated with health outcomes in many medical contexts but has not been explored in collegiate sports medicine. The relationship between administrative and financial oversight models and staffing is also unknown.


  To provide certified athletic trainers, physicians, and other health care and fitness professionals with recommendations based on current evidence regarding the prevention of noncontact and indirect-contact anterior cruciate ligament (ACL) injuries in athletes and physically active individuals.

Concepts: Health care, Medicine, Public health, Knee, Anterior cruciate ligament, Ligament, Anterior cruciate ligament injury, Cruciate ligament


Structural features of health care environments are associated with patient health outcomes, but these relationships are not well understood in sports medicine.


Background :  The knee joint is the second most commonly injured body site after the ankle and the leading cause of sport-related surgeries. Knee injuries, especially of the anterior cruciate ligament (ACL), are among the most economically costly sport injuries, frequently requiring expensive surgery and rehabilitation. Objective :  To investigate the epidemiology of ACL injuries among high school athletes by sport and sex. Design :  Descriptive epidemiology study. Main Outcome Measure(s) :  Using an Internet-based data-collection tool, Reporting Information Online (RIO), certified athletic trainers from 100 nationally representative US high schools reported athlete-exposure and injury data for athletes from 9 sports during the 2007/08-2011/12 academic years. The outcome of interest in this study was ACL injuries. Results :  During the study period, 617 ACL injuries were reported during 9 452 180 athlete exposures (AEs), for an injury rate of 6.5 per 100 000 AEs. Nationally, in the 9 sports studied, an estimated 215 628 ACL injuries occurred during the study period. The injury rate was higher in competition (17.6) than practice (2.4; rate ratio [RR] = 7.3, 95% confidence interval [CI]= 6.08,8.68). Girls' soccer had the highest injury rate (12.2) followed by boys' football (11.1), with boys' basketball (2.3) and boys' baseball (0.7) having the lowest rates. In sex-comparable sports, girls had a higher rate (8.9) than boys (2.6; RR = 3.4, 95% CI = 2.64,4.47). Overall, 76.6% of ACL injuries resulted in surgery. The most common mechanisms of injury were player-to-player contact (42.8%) and no contact (37.9%). Conclusions :  Anterior cruciate ligament injury rates vary by sport, sex, and type of exposure. Recognizing such differences is important when evaluating the effectiveness of evidence-based, targeted prevention efforts.

Concepts: Surgery, Knee, Anterior cruciate ligament, Joint, High school, Anterior cruciate ligament injury, Cruciate ligament, Lateral meniscus