Several benefits have been identified for individuals who regularly participate in sports and exercise. Those benefits include, but are not limited to, reduced risk for premature death due to cardiovascular disease, increased bone density, reduction of hypertension and diabetes, improved weight and body fat control, and improved mental health. Increased sport participation, however, is also accompanied by increased risk of injury. Fortunately, many sports-related injuries are preventable, and physical therapists can play an important role in the education of athletes and the prevention of acute and chronic injuries. The main goal of this special issue is to provide up-to-date commentaries on a wide range of topics related to preventive sports medicine.

J Orthop Sports Phys Ther. 2003; 33(10):556.

Key Words: preventative sports medicine, exercise

Muscles operate eccentrically to either dissipate energy for decelerating the body or to store elastic recoil energy in preparation for a shortening (concentric) contraction. The muscle forces produced during this lengthening behavior can be extremely high, despite the requisite low energetic cost. Traditionally, these high-force eccentric contractions have been associated with a muscle damage response. This clinical commentary explores the ability of the muscle-tendon system to adapt to progressively increasing eccentric muscle forces and the resultant structural and functional outcomes. Damage to the muscle-tendon is not an obligatory response. Rather, the muscle can hypertrophy and a change in the spring characteristics of muscle can enhance power; the tendon also adapts so as to tolerate higher tensions. Both basic and clinical findings are discussed. Specifically, we explore the nature of the structural changes and how these adaptations may help prevent musculoskeletal injury, improve sport performance, and overcome musculoskeletal impairments.

J Orthop Sports Phys Ther. 2003;33(10):557-571.

Key Words: muscle action, plyometrics, strength

Lateral ankle sprains are one of the most common injuries incurred in recreational and competitive athletics. These injuries have a significant impact in terms of cost, athletic participation, and activities of daily living. Prophylactic ankle braces are often used to reduce the risk of injury recurrence when individuals return to athletic participation. The purpose of this clinical commentary is to review the literature and provide our own experience relative to the use of prophylactic ankle bracing. Relatively high incidence rates of ankle sprain injury have been reported for basketball and soccer athletes, military trainees, and individuals with a previous history of ankle sprain injury. Semirigid and laced ankle braces have significantly reduced the incidence of initial and recurrent ankle sprain injuries in athletic and military samples. With few exceptions, these braces do not appear to affect functional performance adversely. The prophylactic use of semirigid ankle braces appears warranted to reduce the incidence of initial and, in particular, recurrent ankle sprain injuries for individuals who participate in activities that have the highest risk for these injuries. Additional research is needed to evaluate the many new braces that are available and in use and their influence on the incidence of ankle sprain injury and functional performance.

J Orthop Sport Phys Ther. 2003;33(10):572-577.

Key Words: brace, compliance, incidence, injury, orthosis, performance

Participation in sports increases the risk of joint injuries that can lead to posttraumatic osteoarthritis, a clinical syndrome caused by trauma-initiated joint degeneration that results in permanent and often progressive joint pain and dysfunction. Minimizing the risk of joint injuries and helping people with osteoarthritis participate in regular physical activity, including some sports, requires understanding of the relationships between joint use, joint injury, and joint degeneration. Lifelong participation in sports that cause minimal joint impact and torsional loading by individuals with normal joints and neuromuscular function does not increase the risk of posttraumatic osteoarthritis. In contrast, participation in sports that subject joints to high levels of impact and torsional loading increases the risk of joint injury and subsequent joint degeneration. Immediate diagnosis and appropriate treatment and rehabilitation following joint injuries decrease the risk of subsequent injuries and posttraumatic osteoarthritis. Individuals with abnormal joint anatomy or alignment, previous significant joint injury, osteoarthritis, joint surgery, joint instability, disturbances of joint or muscle innervation, or inadequate muscle strength have increased risk of joint damage during participation in athletics. These individuals can benefit from regular exercise, including selected sports, but they should have an evaluation of their joint structure and function, muscle strength, and neuromuscular function before participating in vigorous physical activity.

J Orthop Sports Phys Ther. 2003;33(10):578-588.

Key Words: arthritis, cartilage, joints, knee, osteoarthritis

Sudden cardiac death in competitive athletes is a rare event in spite of the large numbers participating in organized sports. These tragic episodes usually receive significant media coverage and stimulate intense discussion in the lay and medical communities about how future occurrences might be avoided. This clinical commentary will review a variety of issues concerning sudden cardiac death in competitive athletes, including epidemiology, causes, screening methods, and potential for prevention.

J Orthop Sports Phys Ther. 2003;33(10):589-593.

Key Words: arrhythmia, cardiovascular system, heart disease, medical screening

Over the last thirty years, participation by girls and women in organized athletics has increased dramatically. This presents unique challenges in the area of sports medicine, orthopaedics, and pediatrics. While the benefits of participation in sports and exercise vastly outweigh the risks of permanent injury, an evolving concern is the number of stress fractures in active women. The female athlete triad ("triad") describes the coexistence of 3 distinct medical conditions that may occur in athletic girls and women. Originally, the triad included eating disorders, amenorrhea, and osteoporosis. Presently, it includes eating disorders/disordered eating behavior, amenorrhea/oligomenorrhea, and decreased bone mineral density (osteoporosis and osteopenia). Briefly, when coupled with inadequate nutrition, the high caloric expenditure of exercise training results in a sustained negative caloric balance or low energy availability, which is exquisitely sensed by the hypothalamus, initiating a complex neuroendocrine adaptive cascade. This cascade is associated with changes in the hypothalamic-pituitary-ovarian axis, such that estrogen levels are decreased, resulting in reproductive dysfunction that may include amenorrhea, oligomenorrhea, or anovulation. Low estrogen in otherwise young healthy women, like menopause, is associated with decreased bone mineral density and increased risk of fractures. The triad is not an inevitable consequence of participation in sports or physical activity at any level; however, exercise may contribute to the disruption of caloric balance. The triad is a complex disorder that requires intervention by a multidisciplinary team. Physical therapists bring a unique expertise to the team. The present review summarizes each component of the triad, component linkage, and the role of physical therapy in prevention, assessment, and intervention.

J Orthop Sports Phys Ther. 2003;33(10):594-614.
 

Key Words: amenorrhea, eating disorders, osteopenia, women athletes

Nutritional supplements and other ergogenic aids have gained widespread use among professional, amateur, recreational, and student athletes for their potential to enhance athletic performance and provide a competitive edge. Creatine monohydrate is one of the more commonly used and potentially beneficial supplements that currently is viewed to be safe. Supplementation with oral creatine augments skeletal muscle creatine concentrations in most individuals, which has been shown to promote gains in lean body mass when used in conjunction with resistance training, to enhance power and strength, and to improve performance in intense exercise, especially during repeated bouts. Young athletes, however, must be cautious about taking creatine because its effects on growth and development are unknown and long-term safety has not been established. Variability in research study designs and small sample sizes have left many questions unanswered regarding the safety and efficacy of chronic supplementation. This is an active area of clinical investigation and the results of ongoing and future research should guide the appropriate use of creatine to enhance athletic performance among athletes of all ages.

J Orthop Sports Phys Ther. 33(10):615-621.
 

Key Words: athletes, ergogenic aid, exercise, nutritional supplement