bluuebunny/crossref_metadata_2025 huggingface dataset:
A NOVEL MOBILE DEVICE BASED HAMSTRING STRENGTH TEST RESULT CAN PREDICT ISOKINETIC HAMSTRING STRENGTH IN PROFESSIONAL FOOTBALL PLAYERS: A STUDY OF RELIABILITY AND VALIDITY
Authors: Lee JWY , Yan SJ , Chan HCK , Yau QKC , SHYung P , Chan KM
Published: March 2014

Background

Isokinetic hamstring strength test is considered as a golden standard for identifying players with increased risk of hamstring strain injuries. However, those testing protocols were time consuming and inconvenient.

Objective

The aim of this study is to examine the reliability and validity of a novel mobile device based hamstring strength test in soccer players. It is hypothesized that a greater forward flexion angle is associated a greater isokinetic hamstring strength.

Design

Cross-sectional study.

Setting

A physical test of hamstring strength in clinical setting.

Participants

30 first team players were recruited from professional football clubs.

Main Outcome Measurements

In the CUHK hamstring strength test (CUHK test), a smartphone was attached on subject's lower back. Subjects were instructed to lower the upper body from a kneeling position until the point he cannot sustain. Trunk forward flexion angle and angular velocity were recorded by the device. In the isokinetic hamstring strength test, it examined subjects' concentric and eccentric hamstring peak torque. Pearson Correlation, linear regression and intra-class correlation coefficient (ICC) were used to examine the validity and reliability.

Results

Result shown that the reliability was good, R=0.845. The CUHK strength test result was highly correlated with isokinetic hamstring peak torque at ecc. 30 degree/second, con. 60 degree/second, con. 240 degree/second respectively, i.e. R=0.81, 0.73 and 0.66. Linear regression analysis shown that the CUHK test was the best to predict isokinetic eccentric hamstring performance at 30 degree/second, R2=0.81, P<.001).

Conclusions

CUHK hamstring strength test is a reliable and valid tool to examine athletes' hamstring muscle performance. Clinician and sports coaches may adopt this test for screening and monitoring athletes or patients during rehabilitation or preseason period. Individualized rehabilitation or strength training recommendation could be made based on the test result.
TWO BIOMARKERS FOR THE SCREENING OF CARDIAC RISK AMONG RUNNERS?
Authors: Le Goff C , Kaux JF , Fillet M , Mélon P , Cavalier E
Published: March 2014

Background

Heart-type fatty acid-binding protein (H-FABP) is a low molecular weight protein involved in the intracellular uptake and buffering of long chain fatty in the myocardium. Troponin T is a component of the contractile apparatus of the striated musculature. Both are early markers for acute coronary syndrome.

Objective

The aim of our study was to compare the results obtained with the H-FABP and the highly sensitive cardiac troponins (hsTnT) and to test their cardiospecificity in healthy runners.

Design

Prospective, cohort study.

Setting

Amateur marathon runners.

Patients

23 runners (marathon) were enrolled.

Interventions

We drowned blood samples at three times: just before (T0), just after (T1), and three hours after the end of the race (T3).

Main outcome measurements

H-FABP and hs-TnT were performed according to the manufacturer's instructions. A linear regression was calculated to observe if there is any correlation between the two biomarkers. Values above the 95th percentile for H-FABP (2.5 ng/mL) and the 99th percentile for hsTnT (14 ng/L) were considered as positive.

Results

At T0, none of the subjects were positive for hsTnT but 35% were positive for H-FABP; at T1, 83% for hsTnT and 100% for H-FABP; at T3, 83% for hsTnT and 96% for H-FABP. At T0, the regression equation was H-FABP T0=3.9454–0.1001×hsTnT T0; at T1: H-FABP T1=51.838–1.7026×hsTnT T1; at T3: H-FABP T3=47.977–1.6193×hsTnT T3. No correlation was observed between the 2 biomarkers.

Conclusion

We observed a significant increase of H-FABP and hsTnT in runners. These markers are independent to each other. These values could biologically correspond to a heart ischemia. These biomarkers could be helpful for the screening of cardiac risk among runners.
THE INFLUENCE OF HIP JOINT CONTROL ON KNEE JOINT VALGUS MOMENT IN YOUNG FEMALE ELITE ATHLETES
Authors: Bencke J , Lauridsen HB , Thorborg K , Hölmich P , Andersen LL , Aagaard P , Zebis MK
Published: March 2014

Background

Biomechanical investigations of sports-specific movements may yield information on which measures could be most efficient for prevention of Anterior Cruciate Ligament (ACL) injuries. High knee valgus moments have been related to increased risk of ACL injury, but further knowledge is needed on how hip strength and hip joint control may influence valgus moments during sidecutting.

Objective

To investigate the relation between isolated hip muscle strength, hip kinematics and knee valgus moments.

Design

Cross-sectional.

Setting

Biomechanical laboratory. Youth elite level.

Participants

97 female handball and football players aged 15–19 yrs selected for the youth national teams were recruited.

Assessment of risk factors

Maximal isometric hip strength was measured during hip abduction, hip extension and hip external rotation [N/kg BM]) by a handheld dynamometer. A standardized sidecutting was performed by each player and hip joint kinematics were measured at initial contact (IC) along with identification of the peak knee joint valgus moment in the contact phase.

Main outcome measurements

Regression analysis was used to determine which of the measured parameters would affect knee valgus moment, and as such represent potential risk factors that should be targeted in future prophylactic training regimes.

Results

No relation between maximal isometric hip muscle strength and knee valgus moment was found. Regression analysis showed weak but significant effect of hip internal rotation at IC and hip abduction at IC on knee valgus moment (r2=.33, P<.001, β-coefficients=0.49 and 0.35 for hip internal rotation and hip abduction, respectively).

Conclusions

The study shows that isometric hip muscle strength did not relate to peak knee valgus moment in young female elite handball and football players. However, increased hip internal rotation and increased hip abduction appeared to negatively influence the magnitude of knee valgus moment during sidecutting, and thus potentially increase the risk of ACL-injury.
INJURY RATE AND INJURY PATTERN AMONG ELITE WORLD CUP SNOWBOARDERS: A 6-YEAR COHORT STUDY
Authors: Major D , Steenstrup SE , Bere T , Bahr R , Nordsletten L
Published: March 2014

Background

There is limited knowledge on the injury rate and injury pattern in the different disciplines among elite snowboarders.

Objective

The aim of this study was to describe and compare the injury rate and injury pattern among the different International Ski Federation (Fédération Internationale de Ski, FIS) World Cup (WC) snowboard disciplines.

Methods

We conducted retrospective interviews with FIS WC snowboard athletes at the end of each season in the period 2007–2012, to register all acute injuries sustained during training or competition during the competitive season requiring attention by medical personnel. To calculate the exposure, we obtained information from result lists from the FIS competition database for all WC competitions for each of the interviewed athletes.

Results

We registered a total of 574 injuries among 1432 athletes, accounting for an overall injury rate of 40.1 injuries/100 athlete/season. A total of 171 injuries occurred during the FIS WC competitions, corresponding to 6.4 injuries/1000 runs. During competition, injury risk was highest in snowboard cross with 11.9/1000 runs, followed by 6.3 in halfpipe, 3.6 in big air and 2.8 in parallel giant slalom/parallel slalom (PGS/PSL). Snowboard cross also had the highest risk of severe injuries (>28 days absence). No differences in injury risk were detected between male and female snowboarders. The most commonly injured body part was the knee (17.8%), followed by the shoulder/clavicle (13.4%) and head/face (13.2%). The risk of knee injury (the most common injury type) and head injury was significantly higher in snowboard cross and halfpipe compared to PGS/PSL.

Conclusions

The risk of injuries was higher in snowboard cross than in halfpipe, big air and PGS/PSL. The most commonly injured body part was the knee. Prevention of snowboard injuries among elite snowboarders should focus on knee injuries, severe injuries and snowboard cross athletes.
DIFFERENCES IN NEUROMUSCULAR ACTIVITY OF QUADRICEPS AND HAMSTRINGS WITH RESPECT TO DIFFERENT LANDING PATTERNS IN FEMALE ATHLETES
Authors: Malfait B , Dingenen B , Staes F , Vanrenterghem J , Verschueren S
Published: March 2014

Background

A high knee abduction moment (KAM) and an erect movement pattern during landing have been suggested as anterior cruciate ligament (ACL) injury risk factors. Previous research focused mainly on determination of parameters with a predictive value for ACL injuries. However, few studies have investigated neuromuscular activity patterns.

Objective

To investigate muscular activity of quadriceps and hamstrings with respect to a flexed or erect landing pattern during drop vertical jumps (DVJ) and its association with the KAM.

Design

Cross-sectional exploratory study.

Setting

Controlled laboratory study.

Participants

48 uninjured female elite athletes were recruited. Based on “peak knee flexion angle” (pKFA) and “peak hip flexion angle” during landing, subjects were subdivided in a “high flexion group” (hip and knee flexion>mean; n=17) or “low flexion group” (hip and knee flexion<mean; n=15).

Risk factor assessement

3D movement analysis was used during DVJ.

Main Outcome Measurements

The root mean square of normalized EMG amplitude was calculated for medial vastus (VM), lateral vastus (VL), medial hamstrings (HM) and lateral hamstrings (HL) from touchdown until pKFA during the first landing of the DVJ. Muscular activity, co-contraction ratios and KAM were compared between groups with independent t-tests.

Results

Subjects that performed landing with low hip and knee flexion (low flexion group), showed a significantly higher activity of the VL (P=.007), a significantly lower VM/VL activity ratio (P=.01) and a significantly higher absolute and normalized (to bodyweight * height) peak KAM compared to the ones with a high flexion landing pattern (respectively P=.03; P=.02). No significant results were found for hamstrings activity.

Conclusions

A more erect landing pattern is associated with higher VL activity, a more disproportional medial/lateral activation pattern, and a higher KAM. These associations provide new support to proposed mechanisms of increased ACL injury risk.
IMPACT OF TRAINING CHARACTERISTICS ON RUNNING-RELATED INJURIES IN RECREATIONAL RUNNERS
Authors: Malisoux L , Urhausen A , Theisen D
Published: March 2014

Background

Most running-related injuries (RRI) are attributed to training errors.

Objective

This study investigated which running training characteristics are potential risk factors for RRI.

Design

Prospective cohort study.

Setting

Recreational distance runners.

Participants

A total of 267 participants accepted to upload weekly all information about running training characteristics, other sport participation and injuries on a dedicated internet platform.

Risk factor assessment

This 9-month follow-up investigated if the risk for RRI was influenced by some of the following running training characteristics: weekly volume (hours/week), weekly frequency (session/week), self-reported session intensity (CR10-Borg Scale), week-to-week absolute change in distance (km/week) and the concomitant use of different pairs of shoes (parallel use of a minimum of 2 different pairs of running shoes).

Main outcome measurements

The primary outcome measure was total volume (hours) of running training and competitions (exposure) until the first RRI (Cox regression analyses). A RRI was defined as any physical complaint located at the lower limbs or lower back region, sustained during or as a result of running practice and impeding planned running activity for at least 1 day.

Results

Overall, 89 participants (33%) recorded an RRI. The total incidence was 6.05 injuries per 1000h of exposure. The adjusted Cox regression analysis revealed that participants who practiced more than 2 hours/week were at a lower risk of RRI (Hazard ratio (HR): 0.539; 95% Confident interval (CI): 0.295-0.986) even when controlling for running experience and training regularity during the previous 12 months. The parallel use of more than one pair of running shoes (HR=0.600; 95% CI=0.369–0.975) and the week-to-week absolute change in distance (HR: 0.882; 68% CI: 0.836–0.931) were also protective factors, while previous injury was a risk factor (HR=1.841; 95% CI=1.185–2.860).

Conclusions

This study identified training characteristics which are related to RRI risk.
ECHOCARDIOGRAPHIC STUDY OF RIGHT VENTRICULAR REMODELING IN TOP-LEVEL GEORGIAN ATHLETES
Authors: Maskhuliva L , Akhalkatsi V , Chelidze K , Kakhabrishvili Z , Matiashvili M , Chabashvili N , Chutkerashvili T
Published: March 2014

Background

There are a large number of studies which have focused on left ventricular (LV) structural and functional characteristics, however insufficient data exist concerning right heart response to exercise in elite athletes of different sporting disciplines.

Objective

To investigate right ventricular (RV) dimensions and function in top-level athletes.

Design

Retrospective study.

Setting

Sports Medicine Clinical Centre.

Participants

124 top-level male athletes (18 cyclists, 62 football and 21 basketball players, 23 wrestlers) and 57 age-matched healthy sedentary controls were studied.All subjects were evaluated with 2D, spectral conventional, and tissue Doppler echocardiography. According to the guidelines of American Society of Echocardiography (ASE), RV subcostal wall thickness, RV diameters (RVD1, RVD2, RVD3, RVOT-Prox, RVOT-Distal) indexed by BSA, and functional parameters (TAPSE, FAC, TD MPI, E/A, E/E') were evaluated.

Main outcome measurements

Athletes of various sport disciplines with respect to RV remodeling.

Results

Morphologic parameters in most of the athletes and in all controls were within normal limits. Increased RV dimensions were found in 43(35%) athletes. RV wall thickness (3,82±0,71 vs. 3,51±0,32 mm) and RV diameters were significantly greater in athletes than in controls (P<.001). Most of the RV parameters in athletes were within the range of Mean and Upper Reference Values (URV), however RVD1 in 34 (27%) and RVD2 in 22 (18%) athletes exceeded URV by ASE criteria. By sporting disciplines RVD1 exceeded URV in 39% cyclists, 25% basketball players, 23% football players, 22% wrestlers. Interestingly, less than half of these athletes (47%) exhibited concomitant LV enlargement. RV functional parameters were in normal limits in athletes as in controls and did not differ (P>.20).

Conclusions

In elite athletes long-term intensive training was associated with RV remodeling, particularly of RV base. RV function was not altered despite significant chamber dilatation. The extent of changes in RV morphology varied between sports: cyclists were more prone to exercise-induced RV structural remodeling.
THE RELATION BETWEEN SELF-EFFICACY, INJURY AND FEAR OF INJURY AMONG ELITE ATHLETES
Authors: McCaffrey A , Mrazik M , Klassen R
Published: March 2014

Background

A growing body of research recognizes the significance of the psychological response to injury among athletes. Yet, to date there is paucity of research that conceptualizes the role which self-efficacy plays in an athlete's response to injury (Wiese-Bjornstal, 2010; Feltzet al., 2008).

Objective

To analysis the hypothetical relation between the types of injuries and the level of self-efficacy and fear to avoid future injuries.

Design

Quantitative retrospective survey style for correlational and regression analysis.

Setting

Elite male athletes in the Canadian Football League (CFL) at preseason training.

Participants

365 pre-season survey reports from CFL players, convenience sampling.

Risk factor assessment

Measures included a self-report measure of self-efficacy (measuring fears around injuries, perceptual control of injuries, and self-efficacy to avoid injuries) and a structured report of the frequency, severity and location of injuries sustained by the athlete in a playing season.

Main outcome measurements

Two main hypotheses were set out before the analysis. First was that injuries would relate to an athlete's level of self-efficacy to avoid injuries in a negative direction. Second was that fears of injuries and perceptual control of injuries could predict an athlete's level of self-efficacy.

Results

Our results demonstrated significant correlations between self-efficacy to injury frequency, severity, and fears of re-injury. Regression analysis revealed variables (injuries, fear of injuries and perceptual control) significantly predict self-efficacy. Results also demonstrate that the location of injury also significantly impact levels of self-efficacy.

Conclusions

This study builds on the research of understanding how athletes are affected by injuries psychologically and how they can deal with the fears and anxieties due to injuries. Practically these results, with the amounting research, can help medical and psychological treatments in dealing with an athlete's self-efficacy and fears.
AN EPIDEMIOLOGICAL STUDY OF INJURY AND ILLNESS IN THE BRITISH SKELETON SQUAD – 2009–2013
Authors: Palmer-Green D , Thomas H , Danny H , Chris P , Kay R , Rod J , Glenn H
Published: March 2014

Background

Injury and illness prevention can have not only athlete health benefits but also potential positive performance gains in elite sport. Valid injury/illness surveillance data is needed in the first step towards prevention.

Objective

Provide injury/illness epidemiology information on the British Skeleton squad.

Design

Longitudinal prospective surveillance study, recording injury/illness, and training/competition exposure data. Definitions for injury/illness, time-loss and performance-restriction were used to identify the rate and severity of athlete injuries/illnesses.

Setting

British skeleton national training centre, including domestic and international training/competition venues between 2009–2013 (4 seasons).

Participants

21 (14 male; 7 female) National team athletes.

Interventions

Standardised report forms for injuries/illnesses were completed by medical, and competition/training exposure by coaching, support staff.

Main outcome measure

Injury/illness rate, severity and causes.

Results

There were 49 training (4.3/1000 athlete training hrs) and 10 competition (14/100 competition starts) injuries, with 10 days and 3 days lost per injury, respectively. Injuries to the thigh (41%), followed by knee and lumbar spine (20% each) were most common, with 4, 13, and 14 days lost per injury, respectively. Muscle strain was the most common type of injury (36%), and lesion of meniscus/disc the most severe (36d), the latter also causing the greatest burden. The most common cause of injury was push start strides and upright sprinting, all resulting in thigh (posterior) muscle strain injuries. There were 16 illnesses (40% squad seasonal prevalence; severity 4d) and respiratory was the most common illness type (80%), occurring most frequently around periods of high training volume, competition and travel.

Conclusions

Prevention initiatives focussed on thigh and lumbar spine injuries, and also illnesses around competitive periods in the season may be beneficial in reducing the number of athlete days lost to training/competition.
FUNCTIONAL AND RTD H/Q RATIO IN 11-16-YEAR OLD MALE FOOTBALL PLAYERS
Authors: Schuth G , Péter A , Hegyi A , Tihanyi J
Published: March 2014

Background

The strength profile of the hamstrings is reported to be important to prevent strain and anterior cruciate ligament (ACL) injuries. There is little information about the functional state of muscles around the knee in young soccer players.

Objective

To determine the differences in the characteristics of knee extensors and flexors in 11–16-year old, male soccer players.

Design

Randomized cross-sectional study.

Setting

Laboratory, youth sports.

Participants

60 randomly selected young male soccer players (11–16 years) – without lower extremity injury history – were assigned into 6 age groups: under 11, 12, 13, 14, 15 and U16 (10 players/group).

Main outcome measurements

The peak torque of isometric hamstring (ICH) and quadriceps (ICQ) (70° of knee flexion), eccentric hamstring (ECH) and concentric quadriceps (CCQ) (60°/s, 10–90° knee flexion range of movement) for both lower extremities were measured on an isokinetic dynamometer (Multicont II). Hecc/Qcc and rate of torque development (RTD) H/Q ratio were calculated 50 ms after the onset of the contraction (RTD H/Q50).

Results

ICH and ICQ significantly differed (P<.05) between U11 and U14 for both legs. There were no significant differences in ICH and in ECH between U13-U16 in the dominant leg, similarly between U14-U16 in the non-dominant leg (P>.05). Hecc/Qcc was significantly higher in the U11 group than in the U16 group (P<.05) in the dominant leg. There were no differences in RTD H/Q50 across age groups for both legs (P>.05).

Conclusions

As eccentric and isometric hamstring peak torques did not differ between U14-U16, hamstring-emphasized strength training is advisable. RTD H/Q50 may have clinical relevance, as most ACL injuries occur 17–50 ms after initial contact. It did not differ between age groups, so the effects of intervention programs should be tested aiming to increase the RTD of the hamstrings.
DO RISK FACTORS DIFFER FOR CONCUSSION AND PROLONGED RECOVERY FOLLOWING CONCUSSION IN ELITE YOUTH ICE HOCKEY PLAYERS?
Authors: Blake T , Meeuwisse WH , Lemke N , Schneider K , Taylor K , Kang j , Emery CA
Published: March 2014

Background

Pediatric concussion risk factor identification will facilitate targeted injury prevention strategy development.

Objective

To examine risk factors for concussion and prolonged recovery amongst elite youth ice hockey players.

Design

Cohort study.

Setting

Community ice rinks and sport medicine clinic (2011/12 season).

Participants

Male and female elite Bantam (13–14 years) and Midget (15-17 years) ice hockey players (n=780).

Assessment of risk factors

Baseline age group, sex, previous concussion history and SCAT2 component scores [Total Symptom Score (TSS), Balance Error Score (BES) and Standardized Assessment of Concussion (SAC) score] were evaluated.

Main outcome measurements

Players with a suspected concussion were referred to a sport medicine physician by team therapists/trainers (n=137). Concussions with time loss of >10 days were defined as prolonged recovery.

Results

Concussion incidence rate ratios (IRR) were estimated using multivariate (concussion) and univariate (prolonged recovery) Poisson regression analyses (cluster and exposure hours adjusted). Males were at greater risk than females [IRR=1.44 (95% CI: 1.09–1.90)]. In females with no concussion history, Bantam players were at greater risk than Midget players [IRR=4.04 (95% CI: 1.24–13.19)]. In Midget players, those with a history of concussion were at greater risk than those with no concussion history [IRR=2.68 (95% CI: 1.61–4.46)]. Players with baseline TSS in the lowest 25th%ile were at greater risk of concussion [IRR=1.50 (95% CI: 1.03–2.18)] and prolonged recovery [IRR=1.88 (95% CI: 1.18–2.99)]. Players with a history of concussion were at increased risk for prolonged recovery [IRR=2.02 (95% CI: 1.29–3.16)]. SAC and BES were not risk factors.

Conclusions

Age group, sex, previous concussion history, and baseline symptom reporting affected the risk of concussion and prolonged recovery in elite youth ice hockey players. This study will inform the development of youth sport concussion prevention strategies.
RETURN-TO-PLAY FOLLOWING INJURY: WHOSE DECISION SHOULD IT BE?
Authors: Shrier I , Safai P , Charland L
Published: March 2014

Background

Return-to-play (RTP) decision-making is required for every injured athlete. However, conflict can and often does emerge between sport medicine clinicians, athletes, coaches and sport associations when engaging in recommended shared decision making processes.

Objective

This study explores differences in professionals' opinion about which criteria should be used for RTP decisions, and who is best able to evaluate them.

Design

Cross-sectional survey.

Setting

Canada.

Participants

Canadian sport medicine physicians, physiotherapists, athletic therapists, chiropractors, massage therapists, athletes, coaches and representatives from the Canadian Olympic Committee, Canada Games, and Canadian Soccer Association.

Risk factor assessment

None.

Main outcome measurements

Descriptive analysis of a 10-min online survey that asked respondents to rate criteria as mandatory to irrelevant on a 5-point Likert scale, and to indicate which profession was best able to evaluate the criteria.

Results

In general, medical doctors, physiotherapists and athletic therapists were considered best able to assess factors related to risk of injury and complications from injury. Each clinician group (except sport massage therapists) generally believed their own profession has the best capacity to evaluate the criteria. Athletes, coaches and sport associations were considered to have the best capacity to assess factors related to competition (desire, psychological and financial impact, and loss of competitive standing). There remained considerable heterogeneity both between and within stakeholder groups.

Conclusions

We found that differences in approach to RTP decisions were generally greater within stakeholder groups compared to between stakeholder groups. If shared decision making is to become the norm in clinical sport medicine, we will need to begin a more fulsome discussion on which discrepancies can be addressed by education and research, and which simply reflect the divergence of values among different individuals.
PRIORITIZING CONCUSSION PREVENTION IN YOUTH ICE HOCKEY: AN ASSESSMENT OF ENGLISH-LANGUAGE CANADIAN NEWSPAPERS AS A VEHICLE FOR EVIDENCE-BASED KNOWLEDGE TRANSLATION
Authors: Blake T , Rock M , Emery CA
Published: March 2014

Background

The extent to which evidence-based injury prevention knowledge is conveyed to the public can have considerable impact on the implementation of injury prevention practice and policy change, which requires significant community engagement and mobilization. Media coverage has been shown to influence the amount of content regarding concussion on social media/networking sites, like Facebook© and Twitter©. Little is known about the extent to which news coverage of concussion reflects current evidence.

Objective

To examine the extent to which English-language Canadian newspaper coverage reflects evidence-based messages regarding the relationship between body checking policy and the burden of concussion in youth ice hockey players.

Design

Retrospective study using qualitative content analysis.

Methods

News releases were collected for primary peer-reviewed research articles conducted through Canadian universities that evaluated the relationship between body checking policy and concussion among pediatric ice hockey players. Coverage of concussion and body checking in youth ice hockey was identified from the five English-language newspapers with the highest reported circulation figures from 2005 to June 2011. The presence of messages extracted from the news releases within the newspaper coverage was examined.

Results

Five research articles and 33 newspaper items were included. One clinical message frame (i.e., concussions in youth ice hockey are a serious clinical problem) and one public health message frame (i.e., concussions in youth ice hockey are a cause for concern) were identified. Every newspaper item contained at least one of the evidence-based messages, and 31 out of 33 (94%) contained both messages.

Conclusion

Evidence-based messages regarding the clinical and public health significance of concussion and the impact of body checking in youth ice hockey were accurately reported in Canadian newspaper coverage. The use of newspapers as a vehicle for knowledge translation would be a valuable addition to prevention implementation strategies requiring community engagement and support.
THE RELATIONSHIP BETWEEN MUSCULOSKELETAL STIFFNESS AND LOWER LIMB INJURY IN ATHLETES: A SYSTEMATIC REVIEW
Authors: Thomson, A
Published: March 2014

Background

Lower limb injuries are prevalent in sports involving running, hopping and jumping. Musculoskeletal lower limb stiffness is a modifiable mechanical property that may be related to injury risk in athletes.

Design

Systematic Review.

Objective

Examine the relationship between musculoskeletal stiffness and lower limb injury in athletes.

Methods

Literature searching was undertaken on 3 electronic databases (MEDLINE/SPORTDiscus/google scholar) up to September 2013. All prospective and case-control studies evaluating lower limb MSK stiffness and injury in athletes were included. Two researchers independently extracted outcome data and assessed the quality of included studies using a modified Downs and Black index. Effect sizes were calculated using RevMan software (version 5.2).

Results

11 studies (6 prospective and 5 case controlled) were identified, comprising a total of 474 participants (378 M, 96 F) with a mean age range of 13–39 years. The majority of studies (9 out of 11) were undertaken on international or elite athletes. Quality index scores ranged from 13 to 16 (max 19). Athletes with a history of unilateral lower limb injury displayed less stiffness when compared to their un-injured contralateral sides. Pooled data from three case control studies also found tendon stiffness was significantly lower in athletes with tendinopathy compared to un-injured matched controls (SMD 0.70, 95% CI 0.07–1.48). Data from prospective studies could not be pooled due to clinical heterogeneity. There was a clear trend that athletes with bilateral differences in leg stiffness or higher mean leg stiffness were more likely to develop a non-contact lower limb injury.

Conclusions

Case controlled studies show a clear relationship between musculoskeletal stiffness and athletic injury. Prospective research provides further evidence that musculoskeletal stiffness may have an important causal role; however this may be implicated by previous injury.
THE IMPACT OF THE FIFA 11+ ON THE STRUCTURE OF SELECT TRUNK AND LOWER EXTREMITY MUSCLES IN ADOLESCENT FEMALE FOOTBALLERS
Authors: Whittaker J , Emery CA
Published: March 2014

Background

The FIFA 11+ is an injury prevention program found to reduce lower-extremity injury risk; however, the mechanisms behind this protective effect are not well understood. One possible explanation is the program addresses trunk and lower-extremity muscle deficits.

Objective

To determine the impact of FIFA 11+ exposure on the structure of select muscles in adolescent female footballers.

Setting

Sport Medicine Clinic.

Design

Sub-study embedded within a cluster-randomized controlled trail (RCT).

Participants

23 female footballers (14–16 years) recruited from three teams that participated in a FIFA11+ implementation strategies RCT.

Intervention:

Participants were recruited from teams randomly assigned to one of two FIFA 11+ delivery groups; coach with unsupervised website access (control; n=11) or, coach with pre-season FIFA 11+ workshop and on-field physiotherapist supervision (comprehensive; n=12).

Main outcome measurements

Pre-post season bilateral sonographic measures of: resting Rectus Abdominis (RA), External/Internal Oblique, Transversus Abdominis, Lumbar Multifidus (MF), Gluteus Medius/Minimus (GMd/GMn), and Vastus Mediallis (VM) thickness; VM width and inter-recti distance (IRD); change in abdominal parameters during an Active Straight Leg Raise (ASLR) and gluteals during hip abduction. Mean (95% CI) pre-post season changes in sonographic parameters were calculated and group means compared with paired t-tests (=0.05).

Results

No differences in 95% CIs existed for pre-post season change in sonographic parameters between participants with low (mean=149±9 exercises/year) and high (mean=314±15 exercises/year) FIFA 11+ exposure. Both groups exhibited significant within-group IRD decreases at rest (low t=8.20, P<.001; high t=5.90, P<.001) and with the ASLR (low t=5.66, P<.001; high t=5.04, P<.001). Further, the lower exposure group demonstrated decreased ASLR percent RA thickness change (t=3.19, P=.01) while the high exposure group exhibited increased resting MF thickness (t=2.26, P=.04).

Conclusions

Different levels of FIFA 11+ exposure in this investigation were not associated with differential changes in the structure of the muscles investigated. Protective mechanisms underlying the FIFA11+ may be associated with alterations in neuromuscular control resulting in IRD and MF adaptations.
ACUTE INJURIES IN 35 SPORTS; INCIDENCES AND SEVERITY
Authors: Åman M , Henriksson-Larsén K
Published: March 2014

Background

Acute injuries in sports are still a problem and the knowledge of incidences and severity in different sports at a national level are limited.

Objective

The aim of this study was to identify high-risk sports with respect to incidence of injury and severity of injuries in 35 sports.

Design

A retrospective cohort study was set up based on a comprehensive database from an insurance company.

Setting

Almost 90% of all athletes in Sweden (in 57/70 sports federations), in all ages and at all competitive levels, have their accident insurance in the same insurance company.

Participants

All licensed athletes in 35 sports during 2009–2011.

Main outcome measurements

The incidence of sport injuries as well as severe injuries (medical disability) were calculated for licensed athletes at a national level. Comparisons between sports, gender, and ages were made. Risk ratio was calculated with median injury incidence as the norm.

Results

Each year approximately 12 000 injuries (in total 35 971 injuries during 2009–2011) and 1 170 000 licensed athletes were eligible for analysis. The incidence of injury was higher in team sport compared to individual sports. Individual sports with highest incidence were motorcycle/snowmobile, skating, and wrestling. Team sports with highest incidence were handball, ice hockey, and rugby. Sports with a large number of injuries were soccer, ice hockey, floor ball, and handball. Highest proportions of medical disabilities were in motorcycle and then in team sports, such as soccer, basket, handball, and floor ball. Risk ratio for motorcycle was 15 and handball 14.

Conclusions

Sports with numerous acute injuries, high incidence and more severe injuries must be the target for prevention actions. This study suggests that team sports and motorcycle should be the object. Next step is to identify injury types, anatomical locations and injury mechanisms to understand how to prevent these injuries.
BETTER PLANNING REDUCES INJURY RISK IN SPORT STUDENTS
Authors: Brink M , Pots M , Lemmink K
Published: March 2014

Background

First year sport students have a considerable risk of injuries. Self-regulatory skills may lower this risk by enabling students to better cope with a sudden increase in physical load (sport participation) and psychosocial stressors (i.e. exams, new social networks).

Objective

The aim of this study was to identify if better self-regulatory skills reduce the risk for athletic injuries in sport students.

Design

Prospective cohort study with seven months injury follow-up.

Setting

Educational setting for students in Physical Education and Sport, Health and Management.

Participants

341 freshmen sports students participated in the study.

Assessment of risk factors

Anthropometric characteristics, sports participation, injury history, and self-regulatory skills (planning, self-monitoring, evaluation, reflection, effort and self-efficacy) were assessed at the start of the academic year by digitalized questionnaires.

Main outcome measurements

The dependent variables were coded as injured (acute or overuse) or non-injured over a seven months period after baseline measures. Data were analyzed using multinomial logistic regression.

Results

A total of 139 athletic injuries were reported. The injury incidence rate per 1000 hours of sports participation was 1.62. Sixty-four percent of the injuries were acute and 36% of the injuries a result of overuse. Increasing hours of sports participation led to a higher risk of overuse injuries (OR: 1.17 95% CI 1.04–1.32), whereas higher scores on planning led to a lower injury risk of overuse injuries (OR: 0.20 95% CI 0.07–0.58). For acute injuries, no significant predictors were found.

Conclusions

Self-regulation seems an important skill in reducing injury risk in sport students, because better planning is associated with a lower injury risk. Future research is needed to study the effects of prevention programs that focus on improving self-regulatory skills.
FACTORS INFLUENCING MUSCLE DAMAGE FROM ISOMETRIC EXERCISE
Authors: Allen T , Jones T , Tsay A , Morgan D , Proske U
Published: March 2014

Background

Most studies of exercise-induced muscle injury have focussed on eccentric contractions, which are known to produce damage and delayed soreness. It is less well known that isometric contractions also produce damage and soreness. This is a study of the damaging effects of isometric exercise.

Objective

To investigate the contributions of factors such as muscle length, force level, duration of contraction and number of contractions to muscle damage following isometric exercise of elbow flexor muscles.

Design

The study comprised 6 separate experiments using a repeated measures design. One arm acted as the experimental arm, while the other acted as the control. Damage measures were obtained pre-exercise, then at 0h, 2h and 24h post-exercise.

Setting

Exercise laboratory.

Participants

50 untrained adults (29 male, 21 female) with no previous upper limb injuries.

Interventions

Exercise with isometric maximum voluntary contractions (MVCs) by each arm. The control arm always performed 30 MVCs, each 4s duration at an included elbow angle of 155° (long muscle length), with 1 min rest between contractions. In 6 experiments, altered variables for the experimental arm included muscle length, number of contractions, duration of contractions and duration of relaxation.

Main outcome measurements

Damage measures: MVC force, soreness rating, tenderness threshold. Exercise measures: muscle force, joint angle, contraction number, contraction duration, relaxation time, total contraction time.

Results

Post-exercise force deficit and muscle soreness were significantly greater for muscles exercised at longer length, despite force being significantly lower at these lengths. A longer relaxation phase did not significantly increase force deficit or soreness. The total contraction time had a greater influence on force deficit than either the number or duration of contractions.

Conclusions

Muscle damage from isometric contractions was principally related to muscle length and total contraction time, not number of contractions. Damage predominantly occurred during the plateau phase of each contraction and not the relaxation phase.
SAFETY ANALYSIS OF SPORT IN SWITZERLAND
Authors: Brügger O
Published: March 2014

Background

Every year, around 400 000 Swiss residents are injured in sports accidents so severely that they need medical treatment. 170 people suffer fatal sports accidents in Switzerland. The bfu–Swiss Council for Accident Prevention–is legally mandated to prevent sports injuries.

Objective

The bfu will present a safety analysis of sport in Switzerland. The aim of a scientific approach is to ensure that decision-makers in the sports sector have a basis available for accident prevention planning.

Design

The method used covers three stages in accident research: in the accident analysis, the extent of accidents will be documented and focal points detected. The risk analysis will weight the factors relating to the focal points that are of relevance for accidents in Switzerland. The intervention analysis will evaluate prevention possibilities in terms of their effectiveness, efficiency and the degree to which they can be implemented to meet Swiss conditions.

Results

The types of sports(-groups) that make up the focal points of accidents–snowsports, off-road biking, mountain sports, watersports (drowning) and football–are the main areas of activity for sports accident prevention. The risk factors identified in the risk analysis are largely specific to each type of sport. They can be allocated to the individual person (particularly risk competence, physical and physiological preconditions) or the setting and the activity respectively (including sports infrastructure, equipment, natural surroundings, official rules). The interventions with the potential for reducing the risk of accidents will be a conclusive list of prevention recommendations that are also specific in nature to the type of sport.

Conclusion

The result of this safety analysis will be the basis for setting an agenda for Switzerland designed to enhance sports safety. Evidence-based recommendations for measures are not always possible given the major gaps in research.
ASSESSMENT OF HAMSTRING MUSCLE VOLUNTARY ACTIVATION: IMPACT OF CONTRACTION MODE AND PREVIOUS INJURY
Authors: Buhmann R
Published: March 2014

Background

Hamstring strain injury (HSI) burdens athletes due to high occurrence and recurrence rates. Previous surface EMG evidence suggests reduced voluntary activation (VA) may contribute to high recurrence rates however no studies have directly assessed VA in previously injured and uninjured hamstrings.

Objective

To determine the extent of hamstring VA in limbs with and without a history of HSI. It was hypothesised that previously injured hamstrings would display eccentric-specific VA deficits relative to uninjured contralateral hamstrings and hamstrings of uninjured controls.

Design

Retrospective, cross-sectional study.

Setting

Recreationally trained males and sub-elite male footballers.

Participants

12 males, with (n=6), and without a unilateral HSI history (n=6) were recruited (average time of 7.7±7.4 months post injury, average age 24.0±2.6 years, stature 180.0±5.7 cm and mass 83.0±7.9 kg).

Assessment of risk factors

Twitch interpolation and sEMG were used to measure hamstring VA during 5 sets of 2 maximal voluntary concentric and eccentric contractions, performed on an isokinetic dynamometer. Peak voluntary and evoked torque were recorded in both limbs.

Main outcome measures

The percentage value for VA calculated by comparing evoked and voluntary torque and surface EMG recordings.

Results

Healthy uninjured limbs displayed VA levels of 96.8%±2.4% during concentric contractions and 93.3%±6.1% during eccentric contractions. Previously injured limbs displayed VA levels of 98.0%±1.1% during concentric contractions and 83.4%±7.1% during eccentric contractions. Eccentric VA was significantly reduced in previously injured limbs compared to the uninjured control group (mean difference=−9.8%, CI=-18.9– −0.7%, P=.033) and uninjured contralateral limb (mean difference=−9.3%, CI=-18.4– −0.3%, P=.043).

Conclusions

Previously injured hamstrings are activated less completely than uninjured hamstrings, specifically during eccentric contractions. Such deficits exist despite successful rehabilitation and a return to sport.
A CASE STUDY OF TWO PREMIERSHIP FOOTBALLERS WITH SICKLE CELL TRAIT USING NOVEL TESTS OF REDOX HOMEOSTASIS
Authors: Catterson P , Moore B , Hodgson A , Lewis N , Newell J , Charles P
Published: March 2014

Background

Sickle cell trait (SCT) is considered a benign heterozygous carrier state (both normal haemoglobin and abnormal HbS) compatible with elite level sport, whereas the autosomal recessive state of sickle cell disease is considered incompatible with strenuous exercise. Increased production of reactive oxygen species occurs in sickle cell disease, evident as increased pro-oxidants (FORT) and reduced anti-oxidants (FORD). This has been demonstrated using a novel point-of-care test (Giziet al.2011). No FORT/FORD data exist in athletes with SCT.

Objective and Participants

It was hypothesized that premiership football players with SCT (n=2) would show altered redox homeostasis compared to non-SCT players (n=19). These data were compared to previously published data on patients with sickle cell disease and controls.

Setting

English Premiership Football Team.

Design and Arisk factor assessment

A cross sectional comparison study design was adopted, and descriptive data are reported. Resting whole blood samples were collected at pre-season and mid-season and analysed immediately for FORT and FORD values. Mean values for non-SCT players were plotted against mean SCT player values (Figure 1).

Results

Figure 1

FORD/FORT values for all players (grey diamonds), SCT players (black squares) and previous data for sickle cell disease (black triangle) and controls (black diamond).

Conclusions

The 2 SCT players in this case study exhibited elevated FORT values, compared to non-SCT players, although they were not extreme outliers, perhaps because athletes are exposed to other sources of pro-oxidants such as exercise. Further research is necessary with a larger cohort in order to further establish the relationship between redox homeostasis and SCT in athletes.

References

Giziet al.(2011) Assessment of oxidative stress in patients with sickle cell disease: The glutathione system and the oxidant–antioxidant status.Blood cells, Molecules and Diseases46, pp. 220–225.
COMPARISON OF ECCENTRIC HAMSTRING STRENGTH AND INJURY RATES BETWEEN PROFESSIONAL AND SEMI-PROFESSIONAL AUSTRALIAN FOOTBALLERS
Authors: Duhig S
Published: March 2014

Background

Hamstring strain injuries (HSI) are the most common injury within Australian football with reports showing no decrease in incidence over two decades.

Objective

To compare differences of HSIs and eccentric hamstring strength, using a field-based testing device, between elite and sub-elite Australian footballers.

Design

A prospective cohort study.

Setting

2 football teams were involved in the study with data collected at their respective club. The first team competes in the elite Australian Football League (AFL) whilst the other competes in the sub-elite North East Australian Football League (NEAFL).

Participants

82 Australian footballers, 41 footballers from a sub-elite NEAFL team and 41 footballers from an elite AFL team participated in the study.

Risk factor assessment

The teams were tested during their preseason, with each footballer performing 3 repetitions of the Nordic hamstring exercise on a field-based testing device. Between limb imbalance and absolute strength were the independent variables.

Main outcome measurements

The dependent variable was the HSI rates, each team was required to record all injuries for the subsequent ‘home and away’ season.

Results

Although not statistically significant,elite AFL players displayed slightly higher average peak torques for the left limb (+17.5N, P=.113) and right limb (+21.1N, P=.09). No difference was observed for between limb imbalance (P=.408) between elite and sub-elite players. However, elite players sustained 3 times more HSIs (9 vs. 3) and missed a greater number of games as a result (28 vs. 6).

Conclusion

Minimal differences were observed between strength and between limb strength imbalances, however, a 60% increase in HSIs was observed in the elite group. We propose that the strength levels displayed within the AFL and additional study is required to assess whether the elite level has higher physical demands and thus requiring greater strength.