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Objective: To determine baseline symptom and neurocognitive norms for non-concussed and previously concussed varsity athletes using the sport concussion assessment tool (SCAT). Study Design: Descriptive cohort study. Setting: University of Calgary. Subjects: 260 male and female university football, ice hockey and wrestling athletes over three seasons (2005–7). Methods: A baseline SCAT was completed during preseason medical evaluation. Subjects were grouped as follows: all participants, men, women, never concussed (NC) and previously concussed (PC). Main Results: The mean age of participants was 20.5 years (range 17–32). In total, 41.2% of all athletes had a total post-concussion symptom scale (PCSS) score of 0. The mean baseline PCSS scores were as follows: all participants 4.29; men 3.52; women 6.39; NC 3.75 and PC 5.25. The five most frequently reported symptoms for all athletes were fatigue/low energy (37% of subjects), drowsiness (23%), neck pain (20%), difficulty concentrating (18%) and difficulty remembering (18%). The median immediate recall score was 5/5 for all groups. Women scored a median of 5/5 on delayed recall, whereas all remaining groups scored a median of 4/5. Months in reverse order were successfully completed by 91.6% of subjects. All participants, women and PC scored a median of 6 on reverse digits, whereas men and NC scored a median of 5. Conclusions: The mean SCAT baseline PCSS score was approximately 5, although just under half of the athletes scored 0. Female athletes scored better on tests of neurocognitive function. PC athletes scored better than NC athletes on all neurocognitive tests except delayed five-word recall.

We quantified the lower extremity dynamics developed during the volleyball spike and block jumps to find out if predictive relations exist between jump dynamics and patellar tendinitis. Lower extremity movement biome chanics were analyzed for 10 members of the 1994 Canadian Men's National Volleyball Team (all right- handed hitters). Based on physical examination, 3 of the 10 players had patellar tendon pain associated with patellar tendinitis at the time of testing. In masked biomechanical and logistic regression analyses, we discovered that the vertical ground-reaction force dur ing the take-off phase of both spike and block jumps was a significant predictor of patellar tendinitis—cor rectly predicting the presence or absence of patellar tendinitis in 8 of 10 players. Deepest knee flexion angle (during landing from the spike jump) predicted 10 of 10 cases correctly for the left knee. The external tibial torsional moment (during the takeoff for the right knee with the spike jump and for the left knee with the block jump) was also a significant predictor of tendinitis. In these players, the likelihood of patellar tendon pain was significantly related to high forces and rates of loading in the knee extensor mechanism, combined with large external tibial torsional moments and deep knee flexion angles.

This review examines recent studies on the effects of exercise on tendons in animal models. Although tendon adaptation to exercise has been described using histology, morphometry, ultrasonography and molecular biology, precise measurements of excess tendon loading during exercise protocols have not been reported. Only a few studies have attempted to evaluate the mechanical strength of exercised tendons. The long term effect of exercise on tendons appears to be positive, but researchers have suggested that periods of mechanical weakness occur in tendons during adaptation to loading conditions. Studies documenting changes associated with the terminal state of pathological tendons are also summarised. Unfortunately, there are no descriptions of tendon tissue in the early stages of overuse injury. Since blood flow is commonly implicated in the emergence of tendinitis, the final section covers recent work on blood flow and tendon physiology. Related research identifying cellular mediators (hyperthermia, hypoxia, and oxidative stress) involved in the development of tendinitis is also presented. Suggestions for further research into exercise loading and the development of tendon overuse injuries are made.

This paper compares the pressure changes in the an terior compartment of the leg when cross-country skiing using the skating method on either skating skis or classic skis. Intracompartmental pressures of the right leg were recorded from the tibialis anterior muscle of 10 subjects at rest and 15 seconds after 10 to 12 minutes of cross-country skiing on a designated course. All subjects completed two trials on different days. In one trial, subjects used skating skis and for the other trial, classic skis were used for the skating technique. Although the average pressure increase was higher for the classic ski trials than for the skating ski trials, the difference was not significant. This finding indicates that cross-country skiers who skate on a classic ski as opposed to a shorter skating ski do not experience a significantly greater increase in their anterior compart ment pressure. Thus, it appears that the type of ski used is not the most significant factor contributing to chronic compartment syndrome.

Background: Although there have been reports of injury rates in men’s World Cup rugby, there has been no research into injury rates in women’s international rugby. Objective: To determine the rate of injury at the 2006 Women’s Rugby World Cup (WRWC). Methods: All participating teams in the 2006 WRWC were enrolled prospectively in this study. Healthcare workers for each team collected data on training and game exposure and information on injuries. Results: 55 players (16%) sustained at least one injury (10.0/1000 player hours); 4 players (1%) sustained two injuries. 45 injuries occurred during games (37.5/1000 player hours) and 14 injuries occurred during practice (12.5/1000 player hours), a statistically significant difference (RR = 12.5, 95% CI 6.9 to 22.8). The injury rate was 39.3/1000 player hours for the forwards and 42.2/1000 player hours for the backs (RR = 1.3, 95% CI 0.7 to 2.3). The front row had the highest injury rate (62.5/1000 player hours). 63.6% of injuries occurred during the tackle. Most injuries occurred to the neck, knee and head/face. The majority of injuries were sprains, muscle injuries and contusions. There were five fractures during the event and four reported concussions. Conclusion: Female players sustained a considerable rate of injury during the 2006 WRWC. Backs had a slightly higher rate of injury than forwards, but the players most often injured were in the front row. The neck/cervical spine and knee were the most commonly injured regions, followed by the head and face. This is the first study to examine injury rates in female rugby players at a World Cup and reports valuable data in this population.

The cause of pain in Achilles tendinopathy is thought to be related to the presence of neovascularization in the tendon as seen on color Doppler ultrasound. Asymptomatic pathology has been observed in patellar tendons of elite athletes. The purpose of this study was to examine the prevalence of Achilles tendon pain and the characteristics of Achilles tendons in a young athletic population. Sixty-four varsity athletes underwent color Doppler ultrasound imaging to determine tendon thickness, presence of degeneration and neovascularization. The presence of swelling and tenderness was determined, and Achilles tendon pain was rated on three visual analogue scales (VAS) (pain during exercise, pain at rest, pain during daily activities) as well as on the VISA-A scale. Tendon symptoms were not related to the presence of neovascularization. There was a low prevalence of Achilles tendinopathy, tenderness, and neovascularization in this population. Neovascularization was seen in both a painful and a non-painful tendon.

Objective To determine the effectiveness of patellar bracing for treatment of patellofemoral pain syndrome (PFPS). Design Prospective, randomized, single-blinded clinical trial. Setting Subjects recruited from the general population of the city of Calgary. Subjects A total of 136 subjects (79 females and 57 males with a total of 197 affected knees) diagnosed with PFPS. Intervention Subjects were randomly assigned to 1 of 4 treatment groups: (1) home exercise program, (2) patellar bracing, (3) home exercise program with patellar bracing, and (4) home exercise program with knee sleeve. Outcome measures The outcome measurements were knee function (KF) and 10-cm visual analogue scale (VAS) pain ratings for 3 different situations: knee pain during sport activity, knee pain 1 hour after sport activity, and knee pain after sitting with knees bent for 30 minutes. The outcome measurements were assessed at baseline and at 3, 6, and 12 weeks. The investigators were blinded to the treatment group of each subject. Calculations were made for 95% confidence intervals for the change in KF and VAS pain ratings from baseline measurement to 12 weeks. Results There was no difference in the 95% confidence intervals in the change of KF and VAS pain ratings among the 4 treatment groups over 12 weeks. Conclusions Symptoms of PFPS improved over time in terms of pain and knee function regardless of the treatment group. Patellar bracing did not improve the symptoms of PFPS more quickly when added to a home program of leg strengthening. However, patellar bracing alone can improve the symptoms of PFPS.

This review examines the diagnosis and management of iliopsoas bursitis and/or tendinitis. It is a relatively uncommon and unrecognised cause of anterior hip pain and anterior snapping hip. In view of its pathology, iliopsoas bursitis might be better referred to as iliopsoas syndrome. It can usually be diagnosed by history and physical examination, though real time ultrasound may be useful in confirming the diagnosis. Magnetic resonance and computerised tomography imaging have limited roles in its diagnosis, but may identify other pathology or surgical lesions. Nonoperative management has not been well established. Surgical management does not guarantee treatment success. There is a need for further research into both diagnostic and treatment options for those patients with iliopsoas bursitis/tendinitis.

It has been reported that there is a relationship between power output and fibre type distribution in mixed muscle. The strength of this relationship is greater in the range of 3–8 rad · s−1 during knee extension compared to slower or faster angular knee extensor speeds. A mathematical model of the force: velocity properties of muscle with various combinations of fast- and slow-twitch fibres may provide insight into why specific velocities may give better predictions of fibre type distribution. In this paper, a mathematical model of the force: velocity relationship for mixed muscle is presented. This model demonstrates that peak power and optimal velocity should be predictive of fibre distribution and that the greatest fibre type discrimination in human knee extensor muscles should occur with measurement of power output at an angular velocity just greater than 7 rad · s−1. Measurements of torque: angular velocity relationships for knee extension on an isokinetic dynamometer and fibre type distribution in biopsies of vastus lateralis muscles were made on 31 subjects. Peak power and optimal velocity were determined in three ways: (1) direct measurement, (2) linear regression, and (3) fitting to the Hill equation. Estimation of peak power and optimal velocity using the Hill equation gave the best correlation with fibre type distribution (r > 0.5 for peak power or optimal velocity and percentage of fast-twitch fibres). The results of this study confirm that prediction of fibre type distribution is facilitated by measurement of peak power at optimal velocity and that fitting of the data to the Hill equation is a suitable method for evaluation of these parameters.

The purpose of the present study was to derive a regression equation relating variables obtained from a series of noninvasive functional tests in a normal subject population to the fiber type distribution of vastus lateralis muscle (VL) determined using muscle biopsy. All functional tests were designed to distinguish between basic properties of Type II fibers (fast twitch fibers) and Type I fibers (slow twitch fibers) and included assessment of peak torque, power output at nine different angular velocities (60 degrees.s-1 to 300 degrees.s-1), as well as a fatigue test consisting of 60 consecutive contractions at 90 degrees.s-1 to establish fatigue resistance of the knee extensor muscles. Using a stepwise multiple regression procedure, relative torque after 53-55 contractions (T55) in the fatigue test and power output at an angular velocity of 280 degrees.s-1 normalized for fat free mass of the thigh (FFMT) were the best predictors for fiber type distribution, explaining 51.8% of the variance in the proportion of Type II fibers in VL. No other measured variable met entering criteria. Subgroup analyses revealed a higher peak torque/FFMT, higher power/FFMT values at angular velocities of 200 degrees.s-1 and higher, and lower relative torque beyond 30 contractions in the fatigue test for the fast twitch group, FTG (subjects with > 60% Type II fibers, N = 8) as compared with the STG (subjects with < 45% Type II fibers, N = 9). Results from the present study suggest that two simple functional tests on a Cybex dynamometer yield reasonable estimates of the fiber type distribution in VL.

Salbutamol and treadmill performance in non-atopic athletes. Med. Sci. Sports Exerc., Vol. 15, No. 6, pp. 520-522, 1983. Nineteen aerobic, non-atopic, athletes (10 females, 9 males) were studied in a double-blind fashion to determine the effect of a therapeutic dosage of salbutamol on pulmonary function, oxygen consumption (VO2max), heart rate (HR), and anaerobic threshold (AT). A placebo and salbutamol (in aerosol form) were administered in a dosage of two puffs four times per day. Forced vital capacity (FVC), FEV1.0, and mid-maximal expiratory flow were assessed prior to a maximal treadmill run, and at 5, 10, and 15 min of recovery. Resting and maximal HR, VO2max, AT, and VE were determined prior to and immediately after the 1-wk experimental period. Pre-test results showed no evidence of airway obstruction in any athlete. There was no significant change in any pulmonary function variable as a result of salbutamol administration. Maximal oxygen consumption showed a slight, nonsignificant (P greater than 0.05) decrease in both the salbutamol and placebo groups. There was also a similar nonsignificant decrease in pulmonary function in both groups. Resting and maximal HR and AT were unchanged. These results indicate that therapeutic administration of a selective beta-2 agonist does not affect pulmonary function or performance-related variables in non-atopic elite athletes.