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Objectives To investigate performance levels and accommodation period to functional knee brace (FKB) use in non-injured braced subjects while completing acceleration, agility, lower extremity power and speed tasks. Design A 2 (non-braced and braced conditions) x 5 (testing sessions) repeated-measures design. Methods 27 healthy male athletes were provided a custom fitted FKB. Each subject performed acceleration, agility, leg power and speed tests over 6 days; five non-braced testing sessions over 3 days followed by five braced testing sessions also over 3 days. Each subject performed two testing sessions (3.5 h per session) each day. Performance levels for each test were recorded during each non-braced and braced trial. Repeated measures analysis of variance, with a post hoc Tukey's test for any test found to be significant, were used to determine if accommodation to FKB was possible in healthy braced subjects. Results Initial performance levels were lower for braced than non-braced for all tests (acceleration p=0.106; agility p=0.520; leg power p=0.001 and speed p=0.001). However, after using the FKB for approximately 14.0 h, no significant performance differences were noted between the two testing conditions (acceleration non-braced, 0.53±0.04 s; braced, 0.53±0.04 s, p=0.163, agility non-braced, 9.80±0.74 s; braced, 9.80±0.85 s, p=0.151, lower extremity power non-braced, 58±7.4 cm; braced, 57±8.1 cm, p=0.163 and speed non-braced, 1.86±0.11 s; braced, 1.89±0.11 s, p=0.460). Conclusions An initial decrement in performance levels was recorded when a FKB is used during an alactic performance task. After 12.0-14.0 h of FKB use, performance measures were similar between the two testing conditions. [ABSTRACT FROM AUTHOR]

BACKGROUND: The present study examines the injury status in women runners who are randomised to receive a neutral, stability or motion control running shoe. METHODS: 81 female runners were categorised into three different foot posture types (39 neutral, 30 pronated, 12 highly pronated) and randomly assigned a neutral, stability or motion control running shoe. Runners underwent baseline testing to record training history, as well as leg alignment, before commencing a 13-week half marathon training programme. Outcome measures included number of missed training days due to pain and three visual analogue scale (VAS) items for pain during rest, activities of daily living and with running. RESULTS: 194 missed training days were reported by 32% of the running population with the stability shoe reporting the fewest missed days (51) and the motion control shoe (79) the most. There was a significant main effect (p<0.001) for footwear condition in both the neutral and pronated foot types: the motion control shoe reporting greater levels of pain in all three VAS items. In neutral feet, the neutral shoe reported greater values of pain while running than the stability shoe; in pronated feet, the stability shoe reported greater values of pain while running than the neutral shoe. No significant effects were reported for the highly pronated foot, although this was limited by an inadequate sample size. CONCLUSION: The findings of this study suggest that our current approach of prescribing in-shoe pronation control systems on the basis of foot type is overly simplistic and potentially injurious. [ABSTRACT FROM AUTHOR]

Background: Tarsal navicular stress fracture is a condition that has curtailed many athletic careers. Management protocols remain varied and somewhat controversial.Hypotheses: (1) Clinical practice does not mirror the recommendations reported from previous case series. (2) Clinical outcome is poor when navicular stress fracture is managed in a variety of ways. (3) Imaging does not correlate strongly with clinical status at long-term follow-up after navicular stress fracture.Study Design: Case series (prognosis); Level of evidence, 4.Methods: From a computer registry, we identified patients who had attended a university sports medicine center between 1996 and 2002 and whose final diagnosis was navicular stress fracture (n = 11) or navicular stress reaction (n = 9). All patients had provided demographic and clinical data at their original evaluation, and all had undergone bone scans and computed tomographic imaging. These data were extracted by chart review. Follow-up clinical and imaging assessments took place a median of 3.7 years later (range, 1-15.7 years). At these assessments, we administered a questionnaire, performed a structured physician examination (blinded to other data), scanned both feet with computed tomography, and obtained magnetic resonance images of the affected foot.Results: Only 2 of 11 patients (18%) with navicular stress fractures received the literature-recommended treatment of at least 6 weeks' nonweightbearing cast immobilization. Of these 11 patients, only 6 (55%) returned to sports at their previous level. Only 3 patients with navicular stress fractures regained normal imaging appearance at follow-up. Pain score, stiffness, sporting success, current sporting involvement, and recurrence/time to recurrence were not statistically associated with computed tomographic or magnetic resonance imaging parameters. Of 9 patients with navicular stress reactions, 7 developed clinical and radiological features of navicular stress fracture, but 6 of 9 patients (67%) returned successfully to sports.Conclusions: Contemporary management of navicular stress fracture differs from that recommended in the literature. This stress fracture prevented almost half of the participants in this study from returning to sports at their previous level. Imaging parameters do not correlate with the clinical assessment of a patient at long-term follow-up of navicular stress fracture. [ABSTRACT FROM AUTHOR]

Objectives: To identify physical activity that is beneficial for the maintenance of bone strength with increasing age by examining the relation between bone mineral density (BMD) and chronic endurance training in men. BMD at the proximal femur, its subregions, and the lumbar spine, and serum testosterone were compared between two groups of long distance runners with more than 20 years of training experience and non-athletic controls.Methods: Runners (n = 12) were divided into (a) high volume runners (n = 7), running 64-80 km a week, and (b) very high volume runners (n = 5), running more than 95 km a week, and compared with non-athletic male controls, exercising in non-endurance oriented activities two to four times a week. BMD (g/cm2) at the total proximal femur, femoral neck, trochanteric region, and lumbar spine was measured by dual energy x ray absorptiometry. Total testosterone (nmol/l) and free testosterone (pmol/l) in serum were measured by radioimmunoassay from single fasting blood samples.Results: Height, weight, and age (range = 40-55 years) were not significantly different between groups. The high volume runners had significantly higher BMD at the total proximal femur (1.09 (0.17) v 0.94 (0.056)), femoral neck (0.91 (0.16) v 0.78 (0.071)), and trochanteric region (0.85 (0.14) v 0.73 (0.053)) than controls (p<0.05). The differences in BMD for the proximal femur between the very high volume runners and the other two groups were not significant. There was no difference in lumbar spine BMD, total testosterone, or free testosterone between groups. However, there was a significant negative correlation between total testosterone (r = -0.73, p<0.01) and free testosterone (r = -0.79, p<0.005) and running volume in the distance runners.Conclusions: Long term distance running with training volumes less than 80 km a week had a positive effect on BMD of the proximal femur. With running volumes greater than 64 km a week, training was inversely related to testosterone levels, but levels remained within the normal range. [ABSTRACT FROM AUTHOR]

Overuse tendinopathies are common in primary care. Numerous investigators worldwide have shown that the pathology underlying these conditions is tendinosis or collagen degeneration. This applies equally in the Achilles, patellar, medial and lateral elbow, and rotator cuff tendons. If physicians acknowledge that overuse tendinopathies are due to tendinosis, as distinct from tendinitis, they must modify patient management in at least eight areas. These include adaptation of advice given when counseling, interaction with the physical therapist and athletic trainer, interpretation of imaging, choice of conservative management, and consideration of whether surgery is an option. [ABSTRACT FROM AUTHOR]

Objectives: There is a paucity of long term studies on exercise training in elderly women. The purpose of this study was to investigate the effects of one year of progressive resistance exercise (PRE) on dynamic muscular strength and the relations to bone mineral density (BMD) in elderly women.Methods: Forty four healthy sedentary women (mean age 68.8 years) volunteered for this study and were randomly assigned to either an exercise group or a control group. The exercise group were involved in three one hour sessions a week for 52 weeks of supervised PRE to strengthen the large muscle groups of the body, while the control group were instructed to continue their normal lifestyle. The exercise circuit included three sets of eight repetitions at 75% of one repetition maximum focused on the large muscle groups. BMD was measured by dual energy x ray absoptiometry (Lunar DPX) at the lumbar spine and at three sites in the proximal femur. Other selected parameters of physical fitness were also measured.Results: Statistical analyses (analysis of covariance) showed significant strength gains (p < 0.01) in bilateral bench press (> 29%), bilateral leg press (> 19%), and unilateral biceps curl (> 20%). No significant difference between groups was evident in body weight, grip strength, flexibility, waist to hip ratio, or the sum of eight skinfolds. Significant relations (p < 0.05) were recorded between dynamic leg strength and the BMD of the femoral neck, Ward's triangle, and the lumbar spine.Conclusions: Significant strength changes, after one year of PRE, were evident in elderly women, and the muscle increases may parallel changes in BMD; however, correlation coefficients were moderate. [ABSTRACT FROM AUTHOR]

Objective: Functional strength deficits associated with chronic isolated posterior cruciate ligament (PCL) insufficiency have received limited attention in the literature. The purpose of this study was to determine the eccentric and concentric isokinetic moment characteristics of the quadriceps and hamstrings in a sample of patients with isolated PCL injury.Methods: Eccentric and concentric mean average and average peak moments were measured for 17 patients with a history of conservatively treated isolated PCL injury using an isokinetic dynamometer. Quadriceps and hamstring isokinetic moments were recorded from 10 degree to 90 degree of knee flexion. Strength ratios were calculated and compared with those reported in the literature for healthy subjects.Results: The hamstrings of the involved side (eccentric/concentric (E/C) ratio = 1.06) were significantly weaker (p<0.05) eccentrically than those of the contralateral side (E/C ratio = 1.29). All hamstrings/quadriceps (H/Q) ratios were less than the universally accepted value of 0.60 and the eccentric H/Q ratio for the injured extremity was significantly lower than the non-injured (p<0.05). In a bilateral comparison, the injured/non-injured (I/N) ratio was less than 1.00 for concentric quadriceps, eccentric quadriceps, and hamstring isokinetic moments. Calculation of the E/C ratio showed that, for the quadriceps, it was 1.08 on the injured side and 1.07 on the non-injured extremity.Conclusions: Eccentric strengthening should be an integral part of functionally rehabilitating the quadriceps and hamstrings of athletes who suffer from the complications associated with chronic isolated PCL insufficiency. [ABSTRACT FROM AUTHOR]

Many elderly women in industrially developed countries are at, or near to, functionally important strength related thresholds and so have either lost, or are in danger of losing, the ability to perform some important everyday tasks. The increased rate of healthcare expenditure due to loss of physical function is a major economic issue. Even though women make up most of the senior population, little current research on the impact of physical activity on strength and function in elderly people has included women. Elderly women typically have more barriers to participation in physical activity than do other groups and because of decreased participation, may possibly experience higher disability rates. Physical activity in old age may delay the progression of osteoporosis and is of paramount importance for maintaining the functional abilities needed to carry out daily tasks. Current research on exercise and the elderly population suggests that strength training may be the exercise mode of choice for maintenance of strength, physical function, bone integrity, and psychosocial health. This review summarises recent research on the impact of strength training on the fitness and health of elderly women and highlights considerations and potential barriers to physical activity that must be taken into account when planning exercise programmes for them. [ABSTRACT FROM AUTHOR]

Objective: Provide a current review of the literature concerning the epidemiology and risk factors for injuries in runners. Data sources: The information in this paper is taken from a review of articles and book chapters (Source: PubMed and MEDLINE, years covered 1966-2006). Conclusions: Understanding the precise causative nature of risk factors in running populations remains a challenging task. Comparison of various works in the literature is impeded by large variations in injury definition, subject population and study design. Weekly running volume continues to be considered a strong risk factor, however more work is needed to determine whether it is the absolute volume, or the increase in volume that is deleterious. Recent research has provided greater insight into the risks that previous injury and lack of full rehabilitation may play in recreational runners starting a training program. Variables related to excessive rear-foot eversion and pronation are frequently sited in combination with the incidence of specific injuries; however, the role of impact characteristics remains in debate. Isokinetic research of hip muscle function is helping to link our understanding of lower extremity kinematics, but requires more research to be proven as a causative factor. Future research in joint coupling and functional training of the complete lower extremity wilI be beneficial in implementing preventative interventions for running populations. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the landing strategies used after discontinuing and continuing the use of a functional knee brace (FKB) while performing a drop jump., Methods: Following published methodology and power analysis, 23 uninjured male athletes, mean age of 19.4 ± 3.0 years, performed seven tests, during three test conditions (nonbraced, braced and removed brace or continued brace use), over 6 days of 12 testing sessions (S) for a total of 38.5 h. Each subject was provided with a custom-fitted FKB. This study focuses on the single leg drop jump kinetics during S12 when subjects were randomly selected to remove the FKB after 17.5 h or continued use of FKB. The time to peak vertical ground reaction forces (PVGRF) and PVGRF were recorded on landing in eight trials., Results: After brace removal, a significantly shorter mean time to PVGRF was recorded (9.4 ± 22.9 msec (3.9%), p = 0.005, 95% confidence interval (95% CI): -168.1, 36.1), while continued brace use required a nonsignificant (n.s.) longer mean duration to achieve PVGRF (19.4 ± 53.6 msec (8.9%), n.s., 95% CI: -49.7, 73.4). No significant mean PVGRF difference was found in brace removal (25.3 ± 65.8 N) and continued brace use (25.1 ± 23.0 N)., Conclusion: Removal of FKB after 17.5 h of use led to a significantly shorter time to achieve PVGRF, while continued brace use for 21 h required a longer duration to achieve PVGRF, suggesting faster and slower knee joint loading, respectively. Understanding the concerns associated with the use of FKB and the kinetics of the knee joint will assist clinicians in counselling athletes about the risks and benefits of using an FKB., Level of Evidence: Level II., (© 2024 European Society of Sports Traumatology, Knee Surgery and Arthroscopy.)

Purpose: To examine the association between day-to-day resting cardiac parasympathetic variability over consecutive non-training days (i.e. weekend) and accumulated exercise stress when quantified using indices of cardiovascular strain. Methods: Twelve international calibre female field hockey players training as part of a national team were participants over a four-week mesocycle prior to a 2016 Olympic qualifying tournament. On-field exercise stress was examined using heart rate (HR) dynamics and quantified as; (1) training load and (2) time (min) spent above anaerobic threshold. The square root of the mean squared differences of successive cardiac cycles (R-R intervals) recorded on Saturday and Sunday were individually calculated and log-transformed prior to being averaged (Ln rMSSDweekend). Day-to-day variation in Ln rMSSD over the weekend was expressed using the coefficient of variation (Ln rMSSD CV ). Non-linear regression analysis examined the association between accumulated exercise stress and Ln rMSSD CV . Results: A quadratic association between each index of exercise stress and Ln rMSSD CV was identified. After converting the coefficient of determination into a correlation coefficient (90% CL), the respective association between Ln rMSSD CV and training load (AU); r  = 0.40 (0.16:0.59) and time above threshold; r  = 0.35 (0.06:0.59) were observed. Conclusion: Ln rMSSD CV derived over consecutive non-training days displayed a moderate, yet significant association between accumulated exercise stress when expressed as global or high-intensity indices of cardiovascular strain. Weekend assessments may offer a practical and appropriate juncture between microcycles to assess the magnitude of perturbation in cardiac autonomic homeostasis prior to entering subsequent training periods.

Objective: Running is an easy way of meeting physical activity recommendations for individuals with knee osteoarthritis (KOA); however, it remains unknown how their cartilage reacts to running. The objective of this pilot study was to compare the effects of 30 min of running on T2 and T1ρ relaxation times of tibiofemoral cartilage in female runners with and without KOA., Methods: Ten female runners with symptomatic KOA (mean age 52.6 ± 7.6 years) and 10 without KOA (mean age 52.5 ± 7.8 years) ran for 30 min on a treadmill. Tibiofemoral cartilage T2 and T1ρ relaxation times were measured using magnetic resonance imaging prior to and immediately after the bout of running. Repeated-measures analyses of covariance (ANCOVA) were conducted to examine between-group differences across scanning times., Results: No Group × Time interactions were found for T2 (P ≥ 0.076) or T1ρ (P ≥ 0.288) relaxation times. However, runners with KOA showed increased T2 values compared with pre-running in the medial and lateral femur 55 min post-running (5.4 to 5.5%, P < 0.022) and in all four tibiofemoral compartments 90 min post-running (6.9 to 11.1%, P < 0.01). A significant group effect was found for T1ρ in the medial femur, with greater values in those with KOA compared with controls., Conclusion: While Group × Time interactions in T2 and T1ρ relaxation times remained statistically insignificant, the observed significant increases in T2 in runners with tibiofemoral osteoarthritis TFOA may suggest slower and continuing changes in the cartilage and thus a need for longer recovery after running. Future research should investigate the effects of repeated exposure to running., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Perrotta, AS, Taunton, JE, Koehle, MS, White, MD, and Warburton, DER. Monitoring the prescribed and experienced heart rate-derived training loads in elite field hockey players. J Strength Cond Res 33(5): 1394-1399, 2019-This study examined the congruence between the prescribed and experienced heart rate-derived training loads over a 5-week periodized mesocycle. Twenty-four elite female field hockey players training as part of a national team were monitored before an (FIH) Hockey World League tournament. Three on-field training sessions per week were prospectively designed focusing on technical, tactical, and physiologically oriented hockey drills. A training load value, modeling the periodized weekly loading scheme, was prescribed for each training session and was calculated using normative training load responses from performing on-field hockey drills. Magnitude-based inferences focusing on the effect size (ES) and a Pearson correlation coefficient (r) were used to examine the degree of difference and the strength of correlation between the prescribed and experienced training loads. A significant correlation was observed between the experienced and prescribed training loads over the 5-week mesocycle (r = 0.92, 90% confidence limit [CL] [0.84-0.96]). The percentage difference and the ES between the achieved and prescribed training loads were as follows: week 1 demonstrated a 2.0% difference (ES = 0.10, 90% CL [-0.22-0.41]), week 2 a -5.4% difference (ES = -0.41, 90% CL [-0.75 to -0.07]), week 3 a -1.5% difference (ES = -0.09, 90% CL [-0.37 to 0.20]), week 4 a 7.1% difference (ES = 0.46, 90% CL [0.14-0.78]), and week 5 a 3.5% difference (ES = 0.18, 90% CL [-0.17 to 0.53]). This investigation demonstrates the efficacy for coaches to prospectively design on-field training sessions using normative training load data to enhance the congruence between the prescribed and experienced training loads over a periodized mesocycle.

High magnitudes and rates of loading have been implicated in the etiology of running-related injuries. Knowledge of kinematic variables that are predictive of kinetic outcomes could inform clinic-based gait retraining programs. Healthy novice female runners ran on a treadmill while 3-dimensional biomechanical data were collected. Kinetic outcomes consisted of vertical impact transient, average vertical loading rate, instantaneous vertical loading rate, and peak braking force. Kinematic outcomes included step length), hip flexion angle at initial contact, horizontal distance from heel to center of mass at initial contact, shank angle at initial contact, and foot strike angle. Stepwise multiple linear regression was used to evaluate the amount of variance in kinetic outcomes explained by kinematic outcomes. A moderate amount of variance in kinetic outcomes (vertical impact transient = 46%, average vertical loading rate = 37%, instantaneous vertical loading rate = 49%, peak braking force = 54%) was explained by several discrete kinematic variables-predominantly speed, horizontal distance from heel to center of mass, foot strike angle, and step length. Hip flexion angle and shank angle did not contribute to any models. Decreasing step length and transitioning from a rearfoot strike may reduce kinetic risk factors for running-related injuries. In contrast, clinical strategies such as modifying shank angle and hip flexion angle would not appear to contribute significantly to the variance of kinetic outcomes after accounting for other variables.

Background: The high rate of running-related injury may be associated with increased peak braking forces (PBFs) and vertical loading rates. Gait retraining has been suggested by some experts to be an effective method to reduce loading parameters., Objectives: To investigate whether PBF could be decreased following an 8-session gait retraining program among a group of female recreational runners and which self-selected kinematic strategies could achieve this decrease., Methods: In this exploratory study, 12 female recreational runners with high PBFs (greater than 0.27 body weight) completed an 8-session gait retraining program with real-time biofeedback of braking forces over the course of a half-marathon training program. Baseline and follow-up kinetics and kinematics were analyzed with a repeated-measures analysis of variance., Results: There was an average reduction of 15% in PBF (-0.04 body weight; 95% confidence interval [CI]: -0.07, -0.02 body weight; P = .001; effect size, 0.62), accompanied by a 7% increase in step frequency (11.3 steps per minute; 95% CI: 1.8, 20.9 steps per minute; P = .024; effect size, 0.38) and a 6% decrease in step length (-5.5 cm; 95% CI: -9.9, -1.0 cm; P = .020; effect size, 0.40), from baseline to follow-up., Conclusion: The gait retraining program significantly reduced the PBF among a group of female recreational runners. This was achieved through a combination of increased step frequency and decreased step length. Furthermore, the modified gait pattern was incorporated into the runners' natural gait pattern by the completion of the program. Based on these results, the outlined gait retraining program should be further investigated to assess whether it may be an effective injury prevention strategy for recreational runners. This study was registered with ClinicalTrials.gov (NCT03302975)., Level of Evidence: Prevention, level 4. J Orthop Sports Phys Ther 2019;49(3):136-144. Epub 7 Dec 2018. doi:10.2519/jospt.2019.8587.

Objectives: To evaluate the perceptions of the general public and healthcare practitioners (HCP) in Canada about the relationship between running and knee joint health, and to explore HCP`s usual recommendations to runners with knee osteoarthritis (KOA)., Methods: Non-runners and runners (with and without KOA) and HCP completed an online survey regarding the safety of running for knee joint health. HCP also provided information related to usual clinical recommendations. Proportions of agreement were compared between non-runners and runners., Results: A total of 114 non-runners, 388 runners and 329 HCP completed the survey. Overall, running was perceived as detrimental for the knee joint by 13.1% of the general public, while 25.9% were uncertain. More uncertainty was reported regarding frequent (33.9%) and long-distance (43.6%) running. Statistical analyses revealed greater proportions of non-runners perceiving running negatively compared with runners. Overall, 48.4% believed that running in the presence of KOA would lead to disease progression, while 53.1% believed running would lead to premature arthroplasty. In HCP, 8.2%, 9.1% and 22.2% perceived that running in general, running frequently, or running long-distances are risk factors for KOA, respectively. 37.1% and 2.7% of HCP typically recommended patients with KOA to modify their running training or to quit running, respectively., Conclusion: High rates of uncertainty among the general public and HCP in Canada outline the need for further studies about running and knee joint health. Filling knowledge gaps will help inform knowledge translation strategies to better orientate the general public and HCP about the safety of running for knee joint health., Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests: Jean-Francois Esculier receives salary from The Running Clinic for teaching post-graduate continuing education to healthcare practitioners and providing lectures about running injury prevention to the public. This does not alter our adherence to PLoS One policies on sharing data and materials”.

Our objective was to prospectively investigate the association of kinetic variables with running-related injury (RRI) risk. Seventy-four healthy female recreational runners ran on an instrumented treadmill while 3D kinetic and kinematic data were collected. Kinetic outcomes were vertical impact transient, average vertical loading rate, instantaneous vertical loading rate, active peak, vertical impulse, and peak braking force (PBF). Participants followed a 15-week half-marathon training program. Exposure time (hours of running) was calculated from start of program until onset of injury, loss to follow-up, or end of program. After converting kinetic variables from continuous to ordinal variables based on tertiles, Cox proportional hazard models with competing risks were fit for each variable independently, before analysis in a forward stepwise multivariable model. Sixty-five participants were included in the final analysis, with a 33.8% injury rate. PBF was the only kinetic variable that was a significant predictor of RRI. Runners in the highest tertile (PBF < -0.27 BW) were injured at 5.08 times the rate of those in the middle tertile and 7.98 times the rate of those in the lowest tertile. When analyzed in the multivariable model, no kinetic variables made a significant contribution to predicting injury beyond what had already been accounted for by PBF alone. Findings from this study suggest PBF is associated with a significantly higher injury hazard ratio in female recreational runners and should be considered as a target for gait retraining interventions., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Perrotta, AS, White, MD, Koehle, MS, Taunton, JE, and Warburton, DER. Efficacy of hot yoga as a heat stress technique for enhancing plasma volume and cardiovascular performance in elite female field hockey players. J Strength Cond Res 32(10): 2878-2887, 2018-This investigation examined the efficacy of hot yoga as an alternative heat stress technique for enhancing plasma volume percentage (PV%) and cardiovascular performance. Ten international caliber female field hockey players completed six 60-minute hot yoga sessions using permissive dehydration over 6 days, followed by a 6-day national team camp. Changes in PV% were examined throughout the intervention and postintervention period. A graded maximal exercise test was performed in a thermoneutral environment (23.2 ± 1.0° C) 24 hours before and 24 hours after intervention. Six days of hot yoga initiated a moderate state of hypovolemia (PV% = -3.5%, 90% confidence limit [CL] [-6.9 to -0.13]), trivial improvements in maximal aerobic power (V[Combining Dot Above]O2max) (effect size [ES] = 0.06, 90% CL [-0.16 to 0.28]), and run time to exhaustion (ES = 0.11, 90% CL [-0.07 to 0.29]). Small meaningful improvements were observed in running speed (km·h) at ventilatory threshold (VT1) (ES = 0.34, 90% CL [-0.08 to 0.76]), VT2 (ES = 0.53, 90% CL [-0.05 to 1.1]), along with adaptations in the respiratory exchange ratio during high-intensity exercise (ES = -0.25, 90% CL [-0.62 to 0.12]). A large plasma volume expansion transpired 72 hours after intervention (PV% = 5.0%, 90% CL [1.3-8.7]) that contracted to a small expansion after 6 days (PV% = 1.6%, 90% CL [-1.0 to 4.2]). This investigation provides practitioners an alternative heat stress technique conducive for team sport, involving minimal exercise stress that can preserve maximal cardiovascular performance over periodized rest weeks within the yearly training plan. Furthermore, improvements in submaximal performance and a delayed hypervolemic response may provide a performance-enhancing effect when entering a 6-day competition period.

Background: Abnormal biomechanics have been cited as a potential risk factor for running-related injury. Many modifiable biomechanical risk factors have also been proposed in the literature as interventions via gait retraining., Aim: To determine which interventions have successfully modified biomechanical variables linked to running-related injury., Study Design: Systematic literature review., Methods: MEDLINE, EMBASE, CINAHL, SportDiscus and PSYCINFO were searched using key terms related to running biomechanics and gait retraining. Quality of included studies was assessed using the modified Downs and Black Quality Index and a best evidence synthesis was performed., Results: 27 studies investigating the effect of biomechanical interventions on kinetic, kinematic and spatiotemporal variables were included in this review. Foot strike manipulation had the greatest effect on kinematic measures (conflicting evidence for proximal joint angles; strong evidence for distal joint angles), real-time feedback had the greatest effect on kinetic measures (ranging from conflicting to strong evidence), and combined training protocols had the greatest effect on spatiotemporal measures (limited to moderate evidence)., Conclusions: Overall, this systematic review shows that many biomechanical parameters can be altered by running modification training programmes. These interventions result in short term small to large effects on kinetic, kinematic and spatiotemporal outcomes during running. In general, runners tend to employ a distal strategy of gait modification unless given specific cues. The most effective strategy for reducing high-risk factors for running-related injury-such as impact loading-was through real-time feedback of kinetics and/or kinematics., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Purpose: The aim of the study was to investigate the landing strategies used by non-injured athletes while wearing functional knee braces (FKB, BR condition) during a drop jump task compared with non-injured, non-braced (NBR condition) subjects and also to ascertain whether accommodation to a FKB was possible by non-injured BR subjects., Methods: Twenty-three healthy male provincial and national basketball and field hockey athletes (age, 19.4 ± 3.0 years) were tested. Each subject was provided with a custom-fitted FKB. Five NBR testing sessions were performed over 3 days followed by five BR testing sessions also over 3 days, for a total of 17.5 h of testing per condition. Each subject performed eight trials of the drop jump task during each testing session per condition. Single-leg peak vertical ground reaction forces (PVGRF) and the time to PVGRF were recorded for each NBR and BR trail., Results: The BR group mean PVGRF at landing was significantly lower (1,628 ± 405 N, 2.1 ± 0.5 BW versus 1,715 ± 403 N, 2.2 ± 0.5 BW, F (1,22) = 6.83, P = 0.01) compared with NBR subjects, respectively. The group mean time to PVGRF was not statistically longer during the BR condition (F (1,22) = 0.967, P = 0.3). Further, an accommodation trend was noted as percent performance difference decreased with continued FKB use., Conclusions: The significantly lower group mean PVGRF while using a FKB could keep traumatic forces from reaching the ACL until the active neuromuscular restraints are activated to provide protection to the knee joint ligaments. Also, accommodation to FKB is possible after approximately 14.0 h of brace use. The results of this paper will assist clinicians in providing information to their patients regarding a FKB ability to offer protection to an ACL-deficient knee or to address concerns about early muscle fatigue, energy expenditure, heart rate, and decrease in performance level., Level of Evidence: Prospective study, Level I.

The purpose of this study was to determine the effects of short-term normoxic and hypoxic exercise on plasma endothelin-1 and nitric oxide levels, and the relationship of arterial compliance and pulmonary artery pressure to endothelin-1. Seven endurance-trained males completed two incremental and two steady-state exercise tests performed at ventilatory threshold in normoxia and hypoxia (fraction of inspired oxygen = 0.14). Plasma endothelin-1was measured throughout steady-state tests. Arterial compliance using applanation tonometry, plasma nitric oxide and pulmonary artery pressure using Doppler echocardiography were measured before and after exercise. Small arterial compliance and pulmonary artery pressure significantly increased following exercise. There were no main effects of condition or time for plasma endothelin-1and nitric oxide levels. There were no significant relationships between plasma endothelin-1 and arterial compliance or pulmonary artery pressure. In conclusion, mechanisms other than the endothelial system may play a role in the exercise-induced changes in small artery compliance in this study population. Moderate hypoxia and a 30-minute steady-state exercise have limited effects on plasma endothelin-1 in endurance-trained males.

Context: Knee braces were introduced in sports approximately 30 years ago. However, the effects of a functional knee brace (FKB) on aerobic and anaerobic performance after fatigue are unknown., Objective: To investigate whether FKB use in noninjured participants hindered performance during aerobic (Léger beep test) and anaerobic (repeated high-intensity shuttle test [RHIST]) tasks., Design: Crossover study., Setting: Laboratory., Patients or Other Participants: Twenty-seven healthy male provincial and national basketball and field hockey athletes (age = 19.4±3.0 years, range, 17-26 years; height = 182.6±6.8 cm, range, 168-196 cm; mass = 80.0±9.1 kg, range, 66-108 kg)., Intervention(s): Each participant was provided a custom-fitted FKB and performed 5 nonbraced (NBR) testing sessions over 3 days, followed by 5 braced (BR) testing sessions over 3 days, for a total of 17.5 hours of testing per condition. During each testing session, participants performed 1 trial of the Léger beep test and 1 trial of the RHIST in each condition., Main Outcome Measure(s): Predicted maximal oxygen consumption (Vo(2) max) and time performance measures were recorded for each NBR and BR trial., Results: Initial performance levels were lower for BR than NBR for both the Léger beep test (BR = 44.3 mL/kg/min, NBR = 47.3 mL/kg/min; F(1,26) = 8.726; P = .007) and the RHIST (BR = 16.5 seconds, NBR = 16.2 seconds; F(1,26) = 13.98, P = .001). However, with continued FKB use, the aerobic performance measure remained higher for only the first 2 BR testing sessions (NBR = 46.9 mL/kg/min, BR = 42.4 mL/kg/min; F(3.0,79.8) = 4.95, P = .003). For the anaerobic test, no performance difference was noted between the testing conditions (NBR = 16.2 seconds, BR = 16.4 seconds; P = .7), whereas fatigue levels were lower during BR testing sessions (NBR = 33%, BR = 31%). After 14.0 hours of FKB use, performance levels were almost equal between the testing conditions (NBR = 47.6 mL/kg/min, BR = 46.1 mL/kg/min)., Conclusions: We found an initial decrement in performance when the FKB was used during an aerobic or anaerobic task. However, after 14.0 hours of FKB use, accommodation to the FKB was possible.

Aim: The objective of this paper was to investigate if performance was hindered in non-injured braced athletes during an anaerobic task. If performance was affected, could accommodation to wearing a knee brace occur and thus decreasing performance hindrance concern while using a functional knee brace (FKB)., Methods: A 2x3 non-braced (NBr) and braced repeated measure factorial design. Five healthy athletes completed all testing. Subjects performed the Repeated High Intensity Shuttle Test (RHIST) over six days (three days NBr and three days braced). Running times were recorded each testing day to determine performance measures and percent fatigue levels while using a FKB and if accommodation to FKB use was possible., Results: Non significant (F1,4=1.42, P=0.299) faster group mean performance time, was recorded for braced subjects relative to the non-braced condition. Although relatively faster performance levels were noted during the braced testing conditions during days 1 and 3 compared to the non-braced condition, these results were also not significant (F2,8=2.82, P=0.118). Lower percent fatigue level was recorded during all three braced days compared to non-braced days. Further, a tendency for accommodation to knee brace trend use was noted as the percentage performance difference between the two conditions had decreased by the last day of testing., Conclusion: Use of a knee brace did not hinder performance once accommodation to using the knee brace occurred and fatigue was not a factor while using a knee brace. Additional research, using a larger sample size and longer testing duration, is required to confirm the potential accommodation trend.

Object: The aim of this study was to evaluate the effectiveness of an educational intervention on concussion knowledge within a sample of junior fourth-tier ice hockey players., Methods: A prospective cohort study, called the Hockey Concussion Education Project, was conducted during 1 junior ice hockey regular season (2009-2010) with 67 male fourth-tier ice hockey players (mean age 18.2 ± 1.2 years, range 16-21 years) from 2 teams. All participating players were randomized into 3 concussion education intervention groups (DVD group, interactive computer module [ICM] group, or control group) before the beginning of the season. Each individual received a preintervention knowledge test prior to the intervention. The DVD and ICM groups received a posttest after the completion of their intervention. All participants were offered the same knowledge test at 15 games (50 days) and 30 games (91 days) later., Results: In the concussion education intervention component no significant group differences were observed at baseline between individuals in the control group and between individuals within the interventional group. At the 15-game follow-up, however, the difference between groups approached significance (F [1, 30] = 3.91, p = 0.057). This group difference remained consistent at the 30-game follow-up., Conclusions: This study demonstrates a positive trend concerning concussion education intervention and knowledge acquisition with either the ICMs or the educational DVD. Both forms of intervention produced a positive and sustainable improvement that approached statistical significance when compared with the control group. The control group demonstrated a negative longitudinal trend concerning concussion knowledge.

Object: The objective of this study was to measure the incidence of concussion (scaled relative to number of athlete exposures) and recurrent concussion within 2 teams of fourth-tier junior ice hockey players (16-21 years old) during 1 regular season., Methods: A prospective cohort study called the Hockey Concussion Education Project was conducted during 1 junior ice hockey regular season (2009-2010) involving 67 male fourth-tier ice hockey players (mean age 18.2 ± 1.2 years, range 16-21 years) from 2 teams. Prior to the start of the season, every player underwent baseline assessments using the Sideline Concussion Assessment Tool 2 (SCAT2) and the Immediate Post-Concussion Assessment and Cognitive Test (ImPACT). The study protocol also required players who entered the study during the season to complete baseline SCAT2 and ImPACT testing. If the protocol was not followed, the postinjury test results of a player without true baseline test results would be compared against previously established age and gender group normative levels. Each regular season game was observed by a qualified physician and at least 1 other neutral nonphysician observer. Players who suffered a suspected concussion were evaluated at the game. If a concussion diagnosis was made, the player was subsequently examined in the physician's office for a full clinical evaluation and the SCAT2 and ImPACT were repeated. Based on these evaluations, players were counseled on the decision of when to return to play. Athlete exposure was defined as 1 game played by 1 athlete., Results: Twenty-one concussions occurred during the 52 physician-observed games (incidence 21.5 concussions per 1000 athlete exposures). Five players experienced repeat concussions. No concussions were reported during practice sessions. A concussion was diagnosed by the physician in 19 (36.5%) of the 52 observed games. One of the 5 individuals who suffered a repeat concussion sustained his initial concussion in a regular season game that was not observed by a physician, and as a result this single case was not included in the total of 21 total concussions. This initial concussion of the player was identified during baseline testing 2 days after the injury and was subsequently medically diagnosed and treated., Conclusions: The incidence of game-related concussions (per 100 [corrected] athlete exposures) in these fourth-tier junior [corrected] ice hockey players was 7 [corrected] times higher than [corrected] previously reported in the literature. This difference may be the result of the use of standardized direct physician observation, diagnosis, and subsequent treatment. The results of this study demonstrate the need for follow-up studies involving larger and more diverse sample groups to reflect generalizability of the findings. These follow-up studies should involve other contact sports (for example football and rugby) and also include the full spectrum of gender, age, and skill levels.

Object: The authors investigated return-to-play duration for initial and recurrent concussion in the same season in 2 teams of junior (16-21-year-old) ice hockey players during a regular season., Methods: The authors conducted a prospective cohort study during 1 junior regular season (2009-2010) of 67 male fourth-tier ice hockey players (mean age 18.2 ± 1.2 years [SD], range 16-21 years) from 2 teams. Prior to the start of the season, every player underwent baseline assessments that were determined using the Sideline Concussion Assessment Tool 2 (SCAT2) and the Immediate Post-Concussion Assessment and Cognitive Test (ImPACT). The study protocol also required players who entered the study during the season to complete a baseline SCAT2 and ImPACT. If the protocol was not followed, the postinjury test results of a player without true baseline test results were compared with previously established age- and sex-matched group normative levels. Each game was directly observed by a physician and at least 1 neutral nonphysician observer. Players suspected of suffering a concussion were evaluated by the physician during the game. If a concussion was diagnosed, the player underwent clinical evaluation at the physician's office within 24 hours. The return-to-play decision was based on clinical evaluation guided by the Zurich return-to-play protocol (contained in the consensus statement of international expert opinion at the 3rd International Conference on Concussion in Sport held in Zurich, November 2008). This clinical evaluation and return-to-play protocol was augmented by the 2 tests (SCAT2 and ImPACT) also recommended by the Zurich consensus statement, for which baseline values had been obtained., Results: Seventeen players sustained a physician-observed or self-reported, physician-diagnosed concussion during a physician-observed ice hockey game. The mean clinical return-to-play duration (in 15 cases) was 12.8 ± 7.02 days (median 10 days, range 7-29 days); the mean number of physician office visits by players who suffered a concussion (15 cases) was 2.1 ± 1.29 (median 1.5 visits). Five of the 17 players who sustained a concussion also suffered a recurrent or second concussion. One of the 5 individuals who suffered a repeat concussion sustained his initial concussion in a regular season game that was not observed by a physician, and as a result this single case was not included in the total of 21 concussions. This initial concussion of the player was identified during baseline testing 2 days after the injury and was subsequently medically diagnosed and treated. The mean interval between the first and second concussions in these 5 players was 78.6 ± 39.8 days (median 82 days), and the mean time between the return-to-play date of the first and second concussions was 61.8 ± 39.7 days (median 60 days)., Conclusions: The mean rates of return to play for single and recurrent concussions were higher than rates cited in recent studies involving sport concussions. The time interval between the first and second concussions was also greater than previously cited. This difference may be the result of the methodology of direct independent physician observation, diagnosis, and adherence to the Zurich return-to-play protocol.

Objective: To report on the effectiveness of sonographically guided injections of hyperosmolar dextrose at reducing the pain associated with chronic plantar fasciitis., Design: Case series., Setting: Ultrasound division of St Paul's Hospital., Patients: 20 referrals (3 men, 17 women; age 51 (SD 13) years) from local sports medicine primary care practitioners who had failed previous conservative treatments., Interventions: A 27-gauge needle administered a 25% dextrose/lidocaine solution under sonographic guidance at 6 week intervals returning for a median of three consultations., Main Outcome Measures: Visual analogue scale (VAS) items for pain levels at rest (VAS1), activities of daily living (VAS2), and during or after physical activity (VAS3) were recorded at baseline and at the final treatment consultation (post-test). A telephone interview conducted an average of 11.8 months after the post-test consultation provided a measure of long-term follow-up., Results: 16 patients reported a good to excellent outcome, while the symptoms in 4 patients were unchanged. There was a significant decrease (p<0.001) in all mean VAS items from pre-test to post-test: VAS1 (36.8 (SD 25.6) to 10.3 (10.9)), VAS2 (74.7 (20.8) to 25.0 (27.7)) and VAS3 (91.6 (9.2) to 38.7 (35.1)) and there were no apparent changes after the follow-up interview., Conclusions: Sonographically guided dextrose injections showed a good clinical response in patients with chronic plantar fasciitis insofar as pain was reduced during rest and activity. Further studies including a control group are needed to validate these outcomes.

Aim: The objective of this paper was to identify the rate, profile, and severity of injuries associated with participating on a provincial/state hockey (field) and compare these data, where possible, with available ice hockey data., Methods: An injury was defined as ''any event, during team or team-related game, practice, and/or activity (on or off the playing surface), requiring any attention by the team's Therapist and/or Physician and subsequent game and/or practice time-loss''. Seventy-five players, under the age of 21 years participated in the study over a 5-year duration. All injury data were collected post-injury. Data were collected on the player position, games versus practice conditions, injury time, injury type, injury etiology, anatomical region and plane injured, injury status, and duration required to return to full activity., Results: A total of 2 828 athletes exposure's and 198 injuries were recorded. The combined injury rate was 70 injuries per 1 000 player game and practice exposures with significantly higher risk of injury resulting during the second half of a game or practice. Backs experienced the highest percentage and have a higher risk of injuries. The predominant injuries sustained included muscle strains, followed by tendonitis, while the highest number of injuries resulted from no contact. The lower back and ankle/foot were the most vulnerable to injury, followed by the knee., Conclusion: From this study it can be concluded that hockey (field) players can experience higher injury rates than ice hockey. Also, field hockey players are at greater risk of injury depending on the playing position and are more likely to be injured during the latter duration of a game and/or practice. In identifying injury trends related to hockey, injury prevention strategies should be developed as players use limited protective equipment.

It is estimated that knee injuries account for up to 60% of all sport injuries, with the anterior cruciate ligament (ACL) accounting for almost half of these knee injuries. These knee injuries can result in high healthcare costs, as an ACL injury is often associated with surgery, long and costly rehabilitation, differing degrees of impairment and potential long-term consequences such as osteoarthritis. The interest in ACL injury prevention has been extensive for the past decade. Over this period, many ACL (intrinsic and extrinsic) injury risk factors have been identified and investigated by numerous researchers. Although prevention programmes have shown potential in decreasing knee ligament injuries, several researchers have suggested that no conclusive evidence has been presented in reducing the rate and/or severity of ACL injuries during sporting competition. Knee braces have been available for the last 30 years and have been used to assist individuals with ACL-deficient and ACL-reconstructed knees. However, research is limited on the use of knee braces (prophylactic and functional) to potentially prevent knee ligament injury in the non-injured population. One possible explanation for the limited research could be that the use of these devices has raised concerns of decreased or impaired athletic performance. In summary, the review of subjective and some objective publications suggests that a functional knee brace may offer stability to an ACL-deficient knee joint; however, research is limited on the use of a knee brace for prophylactic use in non-injured athletes. The limited research could be a result of fear of performance hindrance that has led to poor knee brace compliance.

Purpose: The purposes of this study were to quantitatively examine hip abductor strength in patients presenting with iliotibial band friction syndrome (ITBFS) and to determine whether a multi-modal physiotherapy approach, including hip abductor strengthening, might play a role in recovery., Method: Our observational, pretest-posttest study is one of the first prospective studies in this area. Patients presenting to physiotherapy with unilateral ITBFS were recruited to participate. Participants followed a 6-week rehabilitation programme designed to strengthen hip abductors; strength was measured every 2 weeks using a hand-held dynamometer and compared bilaterally., Results: Sixteen subjects (five men, 11 women) aged 20 to 53 years participated. All but 2 reported running as one of their main physical activities. A trend toward a significant difference in hip abductor strength was found between the injured and uninjured sides at baseline, but this difference disappeared by 6 weeks. Hip abductor strength was significantly related to physical function at weeks 2, 4, and 6. Nine subjects were discharged from physiotherapy after the 6-week period, while the other 7 subjects continued attending for up to 5 months., Conclusions: Hip abductor strengthening appeared to be beneficial in the treatment of ITBFS, but further research on the use of hip abductor strengthening for treatment and prevention of ITBFS is needed.

Objective: Chronic tendinosis of the Achilles tendon is a common overuse injury that is difficult to manage. We report on a new injection treatment for this condition., Subjects and Methods: Thirty-six consecutive patients (25 men, 11 women; mean age, 52.6 years) with symptoms for more than 3 months (mean, 28.6 months) underwent sonography-guided intratendinous injection of 25% hyperosmolar dextrose every 6 weeks until symptoms resolved or no improvement was shown. At baseline and before each injection, clinical assessment was performed using a visual analogue scale (VAS) for pain at rest (VAS1), pain during normal daily activity (VAS2), and pain during or after sporting or other physical activity (VAS3). Sonographic parameters including tendon thickness, echogenicity, and neovascularity were also recorded. Posttreatment clinical follow-up was performed via telephone interview., Results: Thirty-three tendons in 32 patients were successfully treated. The mean number of treatment sessions was 4.0 (range, 2-11). There was a mean percentage reduction for VAS1 of 88.2% (p < 0.0001), for VAS2 of 84.0% (p < 0.0001), and for VAS3 of 78.1% (p < 0.0001). The mean tendon thickness decreased from 11.7 to 11.1 mm (p < 0.007). The number of tendons with anechoic clefts or foci was reduced by 78%. Echogenicity improved in six tendons (18%) but was unchanged in 27 tendons (82%). Neovascularity was unchanged in 11 tendons (33%) but decreased in 18 tendons (55%); no neovascularity was present before or after treatment in the four remaining tendons. Follow-up telephone interviews of the 30 available patients a mean of 12 months after treatment revealed that 20 patients were still asymptomatic, nine patients had only mild symptoms, and one patient had moderate symptoms., Conclusion: Intratendinous injections of hyperosmolar dextrose yielded a good clinical response--that is, a significant reduction in pain at rest and during tendon-loading activities--in patients with chronic tendinosis of the Achilles tendon.

In general, elite climbers have been characterised as small in stature, with low percentage body fat and body mass. Currently, there are mixed conclusions surrounding body mass and composition, potentially because of variable subject ability, method of assessment and calculation. Muscular strength and endurance in rock climbers have been primarily measured on the forearm, hand and fingers via dynamometry. When absolute hand strength was assessed, there was little difference between climbers and the general population. When expressed in relation to body mass, elite-level climbers scored significantly higher, highlighting the potential importance of low body mass. Rock climbing is characterised by repeated bouts of isometric contractions. Hand grip endurance has been measured by both repeated isometric contractions and sustained contractions, at a percentage of maximum voluntary contraction. Exercise times to fatigue during repeated isometric contractions have been found to be significantly better in climbers when compared with sedentary individuals. However, during sustained contractions until exhaustion, climbers did not differ from the normal population, emphasising the importance of the ability to perform repeated isometric forearm contractions without fatigue becoming detrimental to performance. A decrease in handgrip strength and endurance has been related to an increase in blood lactate, with lactate levels increasing with the angle of climbing. Active recovery has been shown to provide a better rate of recovery and allows the body to return to its pre-exercised state quicker. It could be suggested that an increased ability to tolerate and remove lactic acid during climbing may be beneficial. Because of increased demand placed upon the upper body during climbing of increased difficulty, possessing greater strength and endurance in the arms and shoulders could be advantageous. Flexibility has not been identified as a necessary determinant of climbing success, although climbing-specific flexibility could be valuable to climbing performance. As the difficulty of climbing increases, so does oxygen uptake (VO(2)), energy expenditure and heart rate per metre of climb, with a disproportionate rise in heart rate compared with VO(2). It was suggested that these may be due to a metaboreflex causing a sympathetically mediated pressor response. In addition, climbers had an attenuated blood pressure response to isometric handgrip exercises when compared with non-climbers, potentially because of reduced metabolite build-up causing less stimulation of the muscle metaboreflex. Training has been emphasised as an important component in climbing success, although there is little literature reviewing the influence of specific training components upon climbing performance. In summary, it appears that success in climbing is not related to individual physiological variables but is the result of a complex interaction of physiological and psychological factors.

Exercise-induced inspiratory muscle fatigue (IMF) has been reported in males but there are few reports of IMF in females. It is not known if a gender difference exists for inspiratory muscle strength following heavy exercise, as is reported in locomotor muscles. Therefore, the relationship between fatigue and subsequent recovery of maximal inspiratory pressure (MIP) following exercise to maximal oxygen consumption (VO2max) was examined in a group of moderately trained males and females. Eighteen males (23+/-3 years; mean +/- SD) and 16 females (23+/-2 years) completed ten MIP and ten maximal handgrip (HG) strength maneuvers to establish baseline. Post-exercise MIP and HG were assessed successively immediately following a progressive intensity VO2max test on a cycle ergometer and at 1, 2, 3, 4, 5, 10, and 15 min. VO2max, relative to fat-free mass was not statistically different between males (62+/-7 ml kg(-1) min(-1)) and females (60+/-8 ml kg(-1) min(-1)). Males had higher absolute MIP values than females at all time intervals (P<0.05). Immediately following exercise, MIP was significantly reduced in both genders (M=83+/-16%; F=78+/-15% of baseline) but HG values were not different than resting values. MIP values remained depressed for both males and females throughout the 15 min (P<0.05). Differences for MIP between males and females were not statistically significant at any measurement time (P>0.05). The findings in this study conclude that IMF, observed immediately following maximal exercise, demonstrated the same pattern of recovery for both genders.

This study examined the effect of running and cycling on exercise-induced arterial hypoxemia (EIAH) in individuals well trained in each modality. Thirteen male triathletes (X+/-SD: age=36+/-5 years, mass=69+/-8 kg, body fat=12+/-1%) performed progressive exercise to exhaustion during cycle ergometry and treadmill running. Gas exchange was determined, while oxyhemoglobin saturation (SaO(2)) was measured with an ear oximeter. At maximal exercise, the respiratory exchange ratio (1.15+/-0.06 vs. 1.10+/-0.05) and the ventilatory equivalent for oxygen uptake (37.6+/-3.8 vs. 34.2+/-2.7) were greater during cycling vs. running (P<0.05). However, there were no differences at maximal exercise in oxygen uptake (64.4+/-3.2 vs. 67.0+/-4.6 mL kg(-1) min(-1)), SaO(2) (93.4+/-2.8% vs. 92.6+/-2.2%), or the ventilatory equivalent for carbon dioxide (V(E)/VCO(2); 33.1+/-3.1 vs. 31.0+/-3.1), during cycling vs. running, respectively. During submaximal exercise, the V(E)/VCO(2) was less for cycling (26.0+/-1.0) compared with running (29.1+/-0.4; P<0.05), but this had no apparent effect on the SaO(2) response. In conclusion, EIAH was not significantly different during cycling and running in athletes who were well trained in both exercise modalities.

Kleine-Levin syndrome (KLS) is a rare disorder characterised, most notably, by periodic episodes of hypersomnolence and hyperphagia. Associated features of the disorder include a lack of concentration, mood changes, and anxiety. Laboratory tests may show slight changes in the electroencephalogram. However, clinical presentation and laboratory tests are normal during asymptomatic intervals. KLS most often presents in adolescent males, with complete recovery by the 3rd to 4th decade of life. Possible precipitating factors include excessive workload, febrile illness, and respiratory infections. Presented is a classical case of KLS in an adolescent male athlete. The patient's history, complete laboratory results, and symptoms are discussed. Possible treatments for this disorder are also mentioned, along with diagnostic criteria.

Objective: To present a practical approach for preventing running injuries., Quality of Evidence: Much of the research on running injuries is in the form of expert opinion and comparison trials. Recent systematic reviews have summarized research in orthotics, stretching before running, and interventions to prevent soft tissue injuries., Main Message: The most common factors implicated in running injuries are errors in training methods, inappropriate training surfaces and running shoes, malalignment of the leg, and muscle weakness and inflexibility. Runners can reduce risk of injury by using established training programs that gradually increase distance or time of running and provide appropriate rest. Orthoses and heel lifts can correct malalignments of the leg. Running shoes appropriate for runners' foot types should be selected. Lower-extremity strength and flexibility programs should be added to training. Select appropriate surfaces for training and introduce changes gradually., Conclusion: Prevention addresses factors proven to cause running injuries. Unfortunately, injury is often the first sign of fault in running programs, so patients should be taught to recognize early symptoms of injury.

Objectives: Seventeen running training clinics were investigated to determine the number of injuries that occur in a running programme designed to minimise the injury rate for athletes training for a 10 km race. The relative contributions of factors associated with injury were also reported., Methods: A total of 844 primarily recreational runners were surveyed in three trials on the 4th, 8th, and 12th week of the 13 week programme of the "In Training" running clinics. Participants were classified as injured if they experienced at least a grade 1 injury-that is, pain only after running. Logistic regression modelling and odds ratio calculation were performed for each sex using the following predictor variables: age, body mass index (BMI), previous aerobic activity, running frequency, predominant running surface, arch height, running shoe age, and concurrent cross training., Results: Age played an important part in injury in women: being over 50 years old was a risk factor for overall injury, and being less than 31 years was protective against new injury. Running only one day a week showed a non-significant trend for injury risk in men and was a significant risk factor in women and overall injury. A BMI of > 26 kg/m(2) was reported as protective for men. Running shoe age also significantly contributed to the injury model. Half of the participants who reported an injury had had a previous injury; 42% of these reported that they were not completely rehabilitated on starting the 13 week training programme. An injury rate of 29.5% was recorded across all training clinics surveyed. The knee was the most commonly injured site., Conclusions: Although age, BMI, running frequency (days a week), and running shoe age were associated with injury, these results do not take into account an adequate measure of exposure time to injury, running experience, or previous injury and should thus be viewed accordingly. In addition, the reason for the discrepancy in injury rate between these 17 clinics requires further study.

Objective: To assess the hypothesis that subjects exposed to intermittent hyperbaric oxygen treatments would recover from signs and symptoms indicative of delayed-onset muscle soreness faster than subjects exposed to normoxic air., Design: Randomized, double-blinded study with a 4-day treatment protocol., Setting: University-based sports medicine clinic., Participants: Sixteen sedentary female university students., Interventions: All subjects performed 300 maximal voluntary eccentric contractions (30 sets of 10 repetitions per minute) of their nondominant leg (110 to 35 degrees of knee flexion) at a slow speed (30 degrees per second) on a dynamometer to elicit muscle damage and injury. Hyperbaric oxygen treatments consisted of 100% oxygen for 60 minutes at 2.0 atmospheres absolute (ATA), while the control group received 21% oxygen at 1.2 ATA for the same amount of time. Both groups received treatment immediately after the induction of delayed-onset muscle soreness and each day thereafter for a period of 4 days (day 1 postexercise through day 4 postexercise)., Main Outcome Measures: Dependent variables (perceived muscle soreness, isokinetic strength, quadriceps circumference, creatine kinase, and malondialdehyde) were assessed at baseline (preexercise, day 0), 4 hours postexercise (day 1), 24 hours postexercise (day 2), 48 hours postexercise (day 3), and 72 hours postexercise (day 4). Magnetic resonance images (T2 relaxation time/short tip inversion recovery) were assessed at baseline (day 0), 24 hours postexercise (day 3), and 72 hours postexercise (day 5)., Results: Repeated-measures analysis of variance was performed on all of the dependent variables to assess differences between treatment and control groups. Analyses revealed no significant differences between groups for treatment effects for any of the dependent variables (pain, strength, quadriceps circumference, creatine kinase, malondialdehyde, or magnetic resonance images)., Conclusions: The findings of this study suggest that hyperbaric oxygen therapy is not effective in the treatment of exercise-induced muscle injury as indicated by the markers evaluated.

Objectives: The purpose of this study was to determine the effects of a proprioceptive training program (PT) vs. a strength training (ST) program on neuromuscular function after anterior cruciate ligament (ACL) reconstruction. The second purpose was to establish the determinants of functional ability for the operated limb., Methods: Ten participants with unilateral ACL reconstructions were randomly assigned to one of the following 12-week training protocols: (1) isotonic ST, and (2) PT. The outcome measures were: (1) peak torque time of the hamstring muscles (PeakTT), (2) average concentric and eccentric torques of the quadriceps and hamstring muscles, (3) one-legged single hop for distance (SLHD), (4) one-legged time hop (TH), and (5) subjective scores., Results: : There was a significant group by time interaction effect for PeakTT (P = 0.017). The PT group demonstrated greater percent change in isokinetic torques than the ST group at the end of the 12 weeks (P < or = 0.05). Participants in both groups demonstrated similar significant gains in functional ability and subjective scores (P < or = 0.014). Quadriceps strength is a determinant of functional ability for the operated limb (R2 = 0.72)., Conclusions: : Both training protocols influenced PeakTT. The beneficial effects of ST on PeakTT appear to be load-dependent, while sufficient practice may be crucial in maintaining PeakTT improvements induced by PT. Proprioceptive training alone can induce isokinetic strength gains. Restoring and increasing quadriceps strength is essential to maximize functional ability of the operated knee joint.

Objectives: To (a) compare ultrasound (US; including grey scale and colour and power Doppler) and magnetic resonance imaging (MRI; with high resolution and fat saturation sequences) with a clinical yardstick in the evaluation of chronic Achilles tendinopathy, and (b) examine whether either imaging method predicted 12 and 24 month clinical outcome., Methods: Forty five patients with symptoms in 57 Achilles tendons were diagnosed with tendinopathy by an experienced sports medicine doctor. All patients underwent US examination (12 MHz probe) with colour and power Doppler, and 25 consecutive patients also underwent MRI with high resolution T1 weighted and STIR sequences., Results: US identified abnormal morphology in 37 of the 57 symptomatic tendons (65%) and normal morphology in 19 of 28 asymptomatic tendons (68%). Baseline US findings did not predict 12 month clinical outcome. The addition of colour and power Doppler did not improve the diagnostic performance of US. MRI identified abnormal morphology in 19 of 34 symptomatic tendons (56%) and normal morphology in 15 of 16 asymptomatic tendons (94%). Lesser grades of MR signal abnormality at baseline were associated with better clinical status at 12 month follow up., Conclusions: US and MRI show only moderate correlation with clinical assessment of chronic Achilles tendinopathy. Graded MRI appearance was associated with clinical outcome but US was not.

The purpose of this study was, firstly, to investigate the intensity of exercise performance of highly trained ultra-endurance triathletes during the cycling portion of an Ironman triathlon, and, secondly, to examine the anaerobic threshold and its relationship to this performance. Following a peak oxygen consumption (VO(2peak)) test on a cycle ergometer to determine the heart rate (HR(Th,vent)) and power output (PO(Th,vent)) at the ventilatory threshold (Th(vent)), 11 highly trained male triathletes [mean (SEM) age 35.8 (1.6) years, body fat 11.7 (1.2)%. VO(2peak) 67.5 (1.0) ml x kg(-1) x min(-1)] who were participating in an Ironman triathlon, in random order: (1) cycled at their PO(Th,vent) (Bi(Th,vent)) until they were exhausted, and (2) cycled for 5 h at a self-selected intensity (Bi(SSI)). Cycling power output (PO), oxygen uptake (VO(2)), heart rate (HR) and blood lactate concentration ([La(-)](b)) were recorded at regular intervals during these trials, while performance HR was recorded during the cycling phase of the Ironman triathlon. Significantly greater (P < 0.05) values were attained during Bi(Th,vent) than during Bi(SSI) for PO [274 (9) compared to 188 (9) W], VO(2) [3.61 (0.15) compared to 2.64 (0.09) l x min(-1)], and [La(-)](b) [6.7 (0.8) compared to 2.8 (0.4) mmol x l(-1)]. Moreover, mean HR during the Ironman triathlon cycle phase [146.3 (2.4) beats.min(-1); n=7] was significantly greater than mean HR during Bi(SSI) [130 (4) beats x min(-1)], and significantly less than mean HR during Bi(Th,vent) [159 (3) beats x min(-1); all P < 0.05]. However, HR during the cycle portion of the Ironman triathlon was highly related to (r = 0.873; P < 0.05) and not significantly different to HR(Th,vent) [150 (4) beats x min(-1)]. These data suggest that ultra-endurance triathletes cycle during the Ironman triathlon at a HR intensity that approximates to HR(Th,vent), but at a PO that is significantly below PO(Th,vent).