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Many coaches, athletes and sports medicine personnel hold the belief, based on observations and experiences, that massage can provide several benefits to the body such as increased blood flow, reduced muscle tension and neurological excitability, and an increased sense of well-being. Massage can produce mechanical pressure, which is expected to increase muscle compliance resulting in increased range of joint motion, decreased passive stiffness and decreased active stiffness (biomechanical mechanisms). Mechanical pressure might help to increase blood flow by increasing the arteriolar pressure, as well as increasing muscle temperature from rubbing. Depending on the massage technique, mechanical pressure on the muscle is expected to increase or decrease neural excitability as measured by the Hoffman reflex (neurological mechanisms). Changes in parasympathetic activity (as measured by heart rate, blood pressure and heart rate variability) and hormonal levels (as measured by cortisol levels) following massage result in a relaxation response (physiological mechanisms). A reduction in anxiety and an improvement in mood state also cause relaxation (psychological mechanisms) after massage. Therefore, these benefits of massage are expected to help athletes by enhancing performance and reducing injury risk. However, limited research has investigated the effects of pre-exercise massage on performance and injury prevention. Massage between events is widely investigated because it is believed that massage might help to enhance recovery and prepare athletes for the next event. Unfortunately, very little scientific data has supported this claim. The majority of research on psychological effects of massage has concluded that massage produces positive effects on recovery (psychological mechanisms). Post-exercise massage has been shown to reduce the severity of muscle soreness but massage has no effects on muscle functional loss. Notwithstanding the belief that massage has benefits for athletes, the effects of different types of massage (e.g. petrissage, effleurage, friction) or the appropriate timing of massage (pre-exercise vs post-exercise) on performance, recovery from injury, or as an injury prevention method are not clear. Explanations are lacking, as the mechanisms of each massage technique have not been widely investigated. Therefore, this article discusses the possible mechanisms of massage and provides a discussion of the limited evidence of massage on performance, recovery and muscle injury prevention. The limitations of previous research are described and further research is recommended.

Delayed onset muscle soreness (DOMS) is a familiar experience for the elite or novice athlete. Symptoms can range from muscle tenderness to severe debilitating pain. The mechanisms, treatment strategies, and impact on athletic performance remain uncertain, despite the high incidence of DOMS. DOMS is most prevalent at the beginning of the sporting season when athletes are returning to training following a period of reduced activity. DOMS is also common when athletes are first introduced to certain types of activities regardless of the time of year. Eccentric activities induce micro-injury at a greater frequency and severity than other types of muscle actions. The intensity and duration of exercise are also important factors in DOMS onset. Up to six hypothesised theories have been proposed for the mechanism of DOMS, namely: lactic acid, muscle spasm, connective tissue damage, muscle damage, inflammation and the enzyme efflux theories. However, an integration of two or more theories is likely to explain muscle soreness. DOMS can affect athletic performance by causing a reduction in joint range of motion, shock attenuation and peak torque. Alterations in muscle sequencing and recruitment patterns may also occur, causing unaccustomed stress to be placed on muscle ligaments and tendons. These compensatory mechanisms may increase the risk of further injury if a premature return to sport is attempted.A number of treatment strategies have been introduced to help alleviate the severity of DOMS and to restore the maximal function of the muscles as rapidly as possible. Nonsteroidal anti-inflammatory drugs have demonstrated dosage-dependent effects that may also be influenced by the time of administration. Similarly, massage has shown varying results that may be attributed to the time of massage application and the type of massage technique used. Cryotherapy, stretching, homeopathy, ultrasound and electrical current modalities have demonstrated no effect on the alleviation of muscle soreness or other DOMS symptoms. Exercise is the most effective means of alleviating pain during DOMS, however the analgesic effect is also temporary. Athletes who must train on a daily basis should be encouraged to reduce the intensity and duration of exercise for 1-2 days following intense DOMS-inducing exercise. Alternatively, exercises targeting less affected body parts should be encouraged in order to allow the most affected muscle groups to recover. Eccentric exercises or novel activities should be introduced progressively over a period of 1 or 2 weeks at the beginning of, or during, the sporting season in order to reduce the level of physical impairment and/or training disruption. There are still many unanswered questions relating to DOMS, and many potential areas for future research.

Golf biomechanics applies the principles and technique of mechanics to the structure and function of the golfer in an effort to improve golf technique and performance. A common recommendation for technical correction is maintaining a single fixed centre hub of rotation with a two-lever one-hinge moment arm to impart force on the ball. The primary and secondary spinal angles are important for conservation of angular momentum using the kinetic link principle to generate high club-head velocity. When the golfer wants to maximise the distance of their drives, relatively large ground reaction forces (GRF) need to be produced. However, during the backswing, a greater proportion of the GRF will be observed on the back foot, with transfer of the GRF on to the front foot during the downswing/acceleration phase. Rapidly stretching hip, trunk and upper limb muscles during the backswing, maximising the X-factor early in the downswing, and uncocking the wrists when the lead arm is about 30 degrees below the horizontal will take advantage of the summation of force principle. This will help generate large angular velocity of the club head, and ultimately ball displacement. Physical conditioning will help to recruit the muscles in the correct sequence and to optimum effect. To maximise the accuracy of chipping and putting shots, the golfer should produce a lower grip on the club and a slower/shorter backswing. Consistent patterns of shoulder and wrist movements and temporal patterning result in successful chip shots. Qualitative and quantitative methods are used to biomechanically assess golf techniques. Two- and three-dimensional videography, force plate analysis and electromyography techniques have been employed. The common golf biomechanics principles necessary to understand golf technique are stability, Newton's laws of motion (inertia, acceleration, action reaction), lever arms, conservation of angular momentum, projectiles, the kinetic link principle and the stretch-shorten cycle. Biomechanics has a role in maximising the distance and accuracy of all golf shots (swing and putting) by providing both qualitative and quantitative evidence of body angles, joint forces and muscle activity patterns. The quantitative biomechanical data needs to be interpreted by the biomechanist and translated into coaching points for golf professionals and coaches. An understanding of correct technique will help the sports medicine practitioner provide sound technical advice and should help reduce the risk of golfing injury.

Kinesio tape (KT) is an elastic therapeutic tape used for treating sports injuries and a variety of other disorders. Chiropractor, Dr Kenso Kase, developed KT taping techniques in the 1970s. It is claimed that KT supports injured muscles and joints and helps relieve pain by lifting the skin and allowing improved blood and lymph flow. The profile of KT rose after the tape was donated to 58 countries for use during the 2008 Olympic Games, and was seen on high-profile athletes. Practitioners are asking whether they should use KT over other elastic adhesive tapes. The aim of this review was to evaluate, using meta-analysis, the effectiveness of KT in the treatment and prevention of sports injuries. Electronic databases including SPORTDiscus, Scopus, MEDLINE, ScienceDirect and sports medicine websites were searched using keywords 'kinesio taping/tape'. From 97 articles, ten met the inclusion criteria (article reported data for effect of KT on a musculoskeletal outcome and had a control group) and were retained for meta-analyses. Magnitude-based inferences were used to assess clinical worth of positive outcomes reported in studies. Only two studies investigated sports-related injuries (shoulder impingement), and just one of these involved injured athletes. Studies attending to musculoskeletal outcomes in healthy participants were included on the basis that these outcomes may have implications for the prevention of sporting injuries. The efficacy of KT in pain relief was trivial given there were no clinically important results. There were inconsistent range-of-motion outcome results, with at least small beneficial results seen in two studies, but trivial results in two other studies across numerous joint measurements. There was a likely beneficial effect for proprioception regarding grip force sense error, but no positive outcome for ankle proprioception. Seven outcomes relating to strength were beneficial, although there were numerous trivial findings for quadriceps and hamstrings peak torque, and grip strength measures. KT had some substantial effects on muscle activity, but it was unclear whether these changes were beneficial or harmful. In conclusion, there was little quality evidence to support the use of KT over other types of elastic taping in the management or prevention of sports injuries. KT may have a small beneficial role in improving strength, range of motion in certain injured cohorts and force sense error compared with other tapes, but further studies are needed to confirm these findings. The amount of case study and anecdotal support for KT warrants well designed experimental research, particularly pertaining to sporting injuries, so that practitioners can be confident that KT is beneficial for their athletes.

The acceleration magnitudes and number of head impacts in amateur rugby union players over a season of matches, measured via instrumented mouthguard accelerations, were higher than for most sports previously reported. Mean linear acceleration measured over a season of matches was similar to the mean linear accelerations previously reported for youth, high school, and collegiate American football players but lower than that for female youth soccer players. Mean rotational acceleration measured over a season of matches was similar to mean rotational accelerations for youth, high school, and collegiate American football players but less than those for female youth soccer players, concussed American collegiate players, collegiate American football players, and professional American football players.

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The injury epidemiology of competitive power lifters was investigated to provide a basis for injury prevention initiatives in power lifting. Self-reported retrospective injury data for 1 year and selected biographical and training information were obtained via a 4-page injury survey from 82 men and 19 women of varying ages (Open and Masters), body masses (lightweight and heavyweight), and competitive standards (national and international). Injury was defined as any physical damage to the body that caused the lifter to miss or modify one or more training sessions or miss a competition. A total of 118 injuries, which equated to 1.2 +/- 1.1 injuries per lifter per year and 4.4 +/- 4.8 injuries per 1,000 hours of training, were reported. The most commonly injured body regions were the shoulder (36%), lower back (24%), elbow (11%), and knee (9%). More injuries appeared to be of a sudden (acute) (59%) rather than gradual (chronic) nature (41%). National competitors had a significantly greater rate of injury (5.8 +/- 4.9 per 1,000 hours) than international competitors (3.6 +/- 3.6 per 1,000 hours). The relative proportion of injuries at some body regions varied significantly as a function of competitive standard and gender. No significant differences in injury profile were seen between Open and Masters or between lightweight and heavyweight lifters. Power lifting appears to have a moderately low risk of injury, regardless of the lifter's age, body mass, competitive standard, or gender, compared with other sports. Future research should utilize a prospective cohort or case-controlled design to examine the effect of a range of other intrinsic and extrinsic factors on injury epidemiology and to assess the effects of various intervention strategies.