bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hypertensive response to exercise: a marker of altered metabolism in endurance athletes?
Authors: Turmel J , Bougault V , Boulet L P , Poirier P 
Published: March 2011

BackgroundInappropriate high blood pressure response to exercise in non athletes is known to be a predictor for future resting systemic hypertension. However, the relevance of exercise hypertension in endurance athletes is not known.ObjectiveAssess the differences in heart rate variability (HRV), 24-h ambulatory blood pressure monitoring (ABPM) and lipid profile in athletes with an hypertensive response to exercise, and athletes with normal response to exercise.DesignThis study was a prospective cross-sectional study. 47 provincial and national athletes without previous diagnosis of systemic hypertension or other cardiovascular disease, training at least 10 h/week were consecutively recruited. 38 athletes completed the study. Intervention: Athletes underwent an ABPM, a 24-h HRV assessment (Holter), a maximal exercise test and blood samples. Hypertensive response to exercise was defined as systolic blood pressure (SBP) ≥220 mm Hg or diastolic blood pressure (DBP) > 100 mm Hg.ResultsTwo athletes had systemic hypertension (SBP: 139 ± 3, DBP: 81 ± 8 mm Hg) on 24 h-ABPM and 14 athletes showed hypertensive response to exercise (SBP: 243 ± 20, DBP: 77 ± 13 mm Hg). Lower values of high density lipoprotein (HDL) (1.27 ± 0.19 vs 1.51 ± 0.23 g/L, p=0.04) and Apo-A1 (1.31 ± 0.14 vs 1.56 ± 0.15 g/L, p=0.003) were observed in athletes with hypertensive responses to exercise. The latter also had higher values of night time SBP on ABPM compared to athletes with a normal response to exercise (116 ± 6 vs 106 ± 8 mm Hg, p=0.02). No difference was found between both groups regarding HRV indices.ConclusionHigher values of night time SBP on ABPM and lower values of HDL and Apo-A1 were observed in athletes with hypertensive response to exercise. These observations may be the first sign of minor metabolic disturbance in endurance athletes, although parameters remain within de normal values.
Risk factors for patellar tendinopathy: a review of the literature
Authors: van der Worp H , van Ark M , Roerink S D , Pepping G J , van den Akker-Scheek I , Zwerver J 
Published: March 2011

BackgroundPatellar tendinopathy (PT) is an injury which has a high prevalence in sports, especially in those involving jumping. Because successful treatment of PT remains challenging, prevention is of utmost importance. Before effective prevention programs can be developed, it is important to identify the risk factors that play a role in the development of this injury.ObjectiveThe aim of this study was to review the literature and to identify risk factors associated with PT.DesignSystematic review of the literature.SettingA search of the Pubmed, EMBASE and AMED databases was conducted to identify studies. Studies were included in the systematic review if they contained: (1) empirical research that investigated factors associated with PT; and (2) a patient group with PT and a comparison group (or tested for differences across groups in a cross-sectional survey).Assessment of risk factorsThe methodological quality of the studies was assessed with a methodological quality assessment list. A strength of evidence criterion was used to identify risk factors. This criterion took into account the percentage of studies that found an association for a factor and the methodological quality of these studies.Results11 studies were included in the review investigating over 40 potential risk factors. The overall methodological quality score of the studies was low. Potential risk factors were categorised in four groups; demographics, anthropometrics, sports related factors and strength/flexibility. The present review found evidence for two risk factors for PT: waist-to-hip ratio and hip and knee flexibility.ConclusionWaist-to-hip ratio and hip and knee flexibility were identified as risk factors for PT. There is a clear need for high quality studies in order to identify the exact risk factors associated with PT.
Injuries to world cup nordic skiers and telemarkers – data from two seasons
Authors: Flørenes T , Nordsletten L , Heir S , Bahr R 
Published: March 2011

BackgroundThere are no recent data regarding injury risk among elite athletes in the Nordic skiing disciplines and Telemark skiing.ObjectiveTo describe the injury rate in World Cup (WC) ski jumping, cross-country and Telemark skiing.Design/SettingAthletes from selected WC teams (Continental Cup for ski jumping women) were interviewed towards the end of two consecutive winter seasons regarding acute injuries sustained during the competitive seasons. A methodological study has shown retrospective interviews to give the most complete picture for WC athletes. Ski jumpers were also asked if they had had a serious knee injury (absence >28 days) during the last four seasons. Exposure data were extracted from the official database of the International Ski Federation as the number of jumps, kilometres and runs performed and used to calculate the incidence for acute injuries in WC competitions.ResultsAmong 973 athletes, 50 acute injuries were reported in WC competitions (23 time-loss injuries). In ski jumping there were 0.6 (95% CI 0 to 1.4) and 0.4 (0–1.2) time-loss injuries per 1000 jumps in males and females, respectively. In cross-country skiing there were 0.2 (0–0.3) and 0.1 (0–0.2) injuries per 1000 km skied and in Telemark skiing 3.0 (0.8–5.1) and 5.5 (1.4–9.6) injuries per 1000 runs for males and females, respectively. In ski jumping, 3.9% of the female and 2.0% of the male athletes had sustained a severe knee injury during the previous 4 years, most of these were during ski jumping activity.ConclusionThere are few injuries and a low injury risk in the Nordic disciplines. Telemark skiing also has a low incidence, comparable to slalom which has the lowest risk among the alpine skiing disciplines. Although the injury incidence is low in ski jumping, we found that severe knee injuries occur at about the same frequency as in team handball and football.
Intrinsic risk factors and the effects of prophylactic bracing on the development of patellofemoral pain in male subjects
Authors: Van Tiggelen D , Cowan S , Thijs Y , Coorevits P , Witvrouw E 
Published: March 2011

BackgroundThe aetiology of patellofemoral pain (PFP) is multifactorial. Patellofemoral bracing can be used as a preventative method in subjects undergoing strenuous training.ObjectiveIndividuals with intrinsic risk factors for PFP could be identified to provide them with patellofemoral braces as preventative method.SettingMilitary cadets undergo a strenuous basic military training (BMT) of 6 weeks.DesignA prospective cohort study.Participants169 male officer cadets volunteered for the study.Intervention 43 subjects were randomly assigned to the intervention group wearing patellofemoral braces during the BMT.Main outcome measurementsPeak torque of the knee extensor and flexors, the onset of the VMO and VL, the joint position sense (JPS) of the knee, the range of motion and anthropometrical characteristics were measured. A military physical fitness test (MPFT) was assessed prior to the start of their BMT.ResultsAfter BMT less recruits in the brace group developed PFP compared to the control subjects (16.3% vs 33.7%; p=0.042). A delayed onset of the VMO-VL, poor JPS, lower peak torque of the knee extensors and a low score on the MPFT were predictive variables in the development of PFP.ConclusionThe incidence of PFP in predisposed individuals could be downsised using patellofemoral bracing if intrinsic risk factors are identified. Physical intrinsic risk factors predict the development of PFP during strenuous training sessions. The use of the logistic regression model could identify individuals who could derive benefit from patellofemoral bracing during exacting training sessions.
Beijing 2008 olympic games meant danger for the health of athletes? Monitoring of air pollution during games of XXIX olympiade by PM10
Authors: Vetvicka J , Handl M 
Published: March 2011

There has been extensive debate about the impact of air pollution before Olympic games 2008 in Beijing and its influence on health and/or performance of athletes. BOCOG and Chinese authorities give this issue a lot of effort. Also, the IOC and NOCs monitor the situation, communicate with the BOCOG and implement preventive measures. Czech NOC in addition to prevention, decided to own direct measurement of air pollution. Based on the measurement results can then decide about the scheme and selection of athletes training funds, or preventive precautions.Ambient temperature, relative humidity and particulate matter with aerodynamic diameter below 10 ìm (PM10) were measured during and shortly before the Games between August 3 and 24, 2008 in Beijing Olympic Village in Block B3 where devices were placed on the balcony in rooms of the Czech Olympic team. Continuous temperature and relative humidity values were monitored datalogging thermo-hygrometer, and PM10 were made fast to respond DustTrak nephelometer. For comparison, similar measurements were carried out at the same time, also in Prague.Temperature and PM10 concentrations were significantly higher in the week preceding Olympic Games. During the Games, however, these parameters decreased significantly. Relative humidity was a lower one during pre-Games than during Games.Announced drastic measures to reduce emissions from industry, transport and construction are likely to bring their positive influence. Significant effects were also favourable climatic conditions, which decreased ambient temperature and frequent rains are likely to have contributed to an unprecedented improvement of pollution conditions.According to our results we can conclude that athletes in Beijing were significantly fewer health risk due to air quality than expected pessimistic assumptions.
Jumping ability and change of jumping ability as a risk factor for developing jumper's knee? Data from the patellar tendinopathy cohort 2006–2010
Authors: Visnes H , Bahr R 
Published: March 2011

BackgroundPrevious studies on high level athletes has shown that players with jumper's knee jumps as high and perhaps even higher than the symptom-free athletes. The reason for this difference is unknown, and we know little about when this difference occurs.ObjectiveAssess the Jumping ability and change of this ability as a risk factor for developing jumper's knee.DesignProspective cohort study.ParticipantsElite volleyball players at junior high school (Top Volley Norway) at Sand, Norway.MethodStandardised jumping on the power platform (Boscotest). Standing jump (SJ) and countermovement jump (CMJ) were tested at baseline and then twice a year. The jumper's knee diagnosis was based on a standardised clinical examination.ResultsA total of 113 symptom-free students were included, with a mean observation time of 1.8 years. 19 of these developed jumper's knee (16 boys and three girls). The three symptomatic women these were excluded in the analysis. The groups were equal at baseline; asymptomatic athletes had SJ of mean 27.5 cm and CMJ at 35.0 cm, while the jumper's knee group had SJ at 28.0 cm (p=0.67 vs asymptomatic) and CMJ (37.2 cm (p=0.10). Jumping ability changed in both groups. For the asymptomatic it was SJ: 5.5 cm (95% CI 1.9 to 9.1) for and CMJ: 6.0 cm (4.1–7.9) while the corresponding results in jumper's knee group was SJ: 3.7 cm (−1.8 to 9.3) (ANOVA, p=0.003) and CMJ: 4.5 cm (0.3 to 8.8) (ANOVA, p=0.001).ConclusionThere is no difference at baseline between the men who developed jumper's knee with those who remained asymptomatic. Those who remained asymptomatic, however, increased their jumping ability more than those who developed a finding that conflict with data from previous cross-sectional studies.
Cross-training and injury risk in british olympic distance triathletes
Authors: Vleck V , Alves F Bessone 
Published: March 2011

BackgroundTriathlon injury research is in its early stages- with no consensus on injury definition and recording methods having been reached, and few prospective data yet available. Levyet al., (1986) suggested that less injury may occur within this sport than in its component disciplines. Massiminoet al., (1988) proposed the opposite.ObjectiveTo determine whether swim, cycle and or run training exert a cumulative stress effect on triathlon overuse injury (OU) risk.DesignSeven month prospective longitudinal training diary based survey, from the endurance base period up to World Championships.SettingBritish Olympic distance specialists.ParticipantsTop 50 finishers at their non-drafting National Championships in the year of, or year prior to, the study.Assessment of risk factorsBoth absolute (ie, duration) and derived training variables were assessed. Derived variables included both training that was weighted for each of five intensity levels it comprised, and combined training for more than one discipline. Log values (% difference from the previous week) and (difference from the previous week) for training variables for 1, 2, 3, and 4 weeks prior to injury were used.Main outcome measurements‘New OU’ was used as the dependant variable in a binary logistic regression analysis, involving combinations of 1–4 training related variables. Anatomical location, discipline(s) that OU was attributed to (on first and subsequent occurrence(s), and performance decrement (PD) were also assessed.ResultsReturn rates were 43, 38, 33, 26, 21, 14 and 11 for each consecutive month. 60% of athletes reported OU with concomitant PD at least once. New OU was associated with an increase in the log of combined weighted cycle and run training in levels 3, 4 and 5 two weeks prior to onset (p<0.05).ConclusionThe extent to which cycle and run training have a cumulative effect on triathlon injury risk deserves further investigation.
Effects of olympic style taekwondo kicks on an instrumented head-form and resultant head injury measures
Authors: Fife G , Pieter W , O'sullivan D , Cook D , Kaminski T 
Published: March 2011

BackgroundIn taekwondo (TKD), concussion incidence is four times greater than in American football. Biomechanical investigations on concussion in TKD is sparse.ObjectiveTo examine differences in TKD kicks on resultant head linear acceleration (RLA), head injury criterion (HIC15) and peak head velocity (HVEL).DesignBetween-groups.SettingBiomechanics laboratory.Participants12 elite male TKD athletes (22.5+3.5 years, 176.9+7.3 cm, 70.9+8.6 kg).InterventionsFive head kicks (round kick (RK), front leg axe kick, clench-axe kick (CA), jump spin back kick, jump spin hook kick (JH)) were randomly performed five times each. A Hybrid II Crash Dummy head (H2D) was instrumented with a tri-axial accelerometer (PCB Piezotronics-356A66) mounted inside the H2D head. The H2D was fixed to a height adjustable frame and fitted with a protective TKD helmet. Acceleration data were captured using Qualisys Track Manager (Gothenburg, Sweden) and processed in accordance with SAE J211-1.Main outcome measurementsRLA, HIC and HVEL.ResultsThe RK (130.11±51.67 g) produced a higher RLA than the CA (54.95±20.08 g, p<0.001, d=1.84) and a higher HIC15 than the JH (672.74±540.89 vs 300.19±144.35, p<0.001, ES=0.97). The range of the RLA by the RK was 60.50–217.33 g, while the CA was 26.34–99.02 g. The HIC15 range for the RK was 128.40–1608.70 and the JH, 63.90–573.00. There was no difference in HVEL of the RK (4.73±1.67 m/s, range: 3.36–9.52 m/s) and that of the JH (4.43±0.78 m/s, range: 3.00–5.54 m/s) (p=0.977, ES<0.01).ConclusionOur investigations are the first to identify the high-magnitude head impacts in TKD. A previous report suggests an HIC15 concussion threshold of >200. The RK is of concern because it is the most common technique and most common cause of concussion in TKD and has a high RLA and HIC15. Prevention of concussion in TKD should focus on employing qualified medical personnel, injury monitoring, and safer equipment.
The impact of fitness level on self-report of concussion symptoms
Authors: Lebrun C , Mrazik M , Naidu D , Matthews-White J , Game A 
Published: March 2011

BackgroundThe diagnosis and management of concussion in sport rely heavily on self-report of symptoms by the athlete. However, many symptoms commonly reported after a concussion (headache, nausea, fatigue, etc.) may be influenced by other factors. Fatigue is a frequent complaint, but may actually be a function of level of physical fitness.ObjectiveTo evaluate the role of physical fitness on self-report of concussion symptoms in collegiate athletes and students, during baseline testing.DesignProspective repeated measures.Participants125 subjects were recruited, including 95 collegiate athletes and 30 undergraduate students (83 males and 42 females). Athletes were screened for medical and psychological conditions. No athlete had a recent history of concussion.InterventionSubjects completed the Standardised Concussion Assessment Tool (SCAT1) at three time periods: prior to a Leger (Beep) test, within 10 min of test completion, and within 24 h. The Leger test has established validity and reliability to estimate an athlete's V02 maximum and overall fitness levels.Main outcome measuresEstimated V02 max (Leger test) and symptom scores on the SCAT1.ResultsSubjects were grouped into three levels of fitness according to criteria established by the American College of Sports Medicine (2010). A 3×3 repeated-measures ANOVA was not significant for the overall model but showed a significant interaction between time and fitness level (F (2, 121)=3.50, p=0.02). Post-hoc analysis revealed significant differences in report of symptoms among the three fitness groups at baseline and immediately post-activity, but not at 24 h.ConclusionResults provide evidence of a moderating effect of fitness level on report of concussion symptoms at baseline, even in healthy adults. Specifically, exercise can induce symptom reporting, and may a function of an athlete's level of conditioning. Sport medicine professionals making decisions following concussion need to consider an athlete's level of fitness when evaluating post-concussion symptoms.
Are pre-season reports of neck pain, dizziness and/or headaches risk factors for concussion in male youth ice hockey players?
Authors: Schneider K , Emery C , Kang J , Schneider G , Meeuwisse W 
Published: March 2011

BackgroundConcussion is a commonly encountered injury associated with potential long-term sequelae. No previous studies have evaluated dizziness, neck pain and headache as potential risk factors for concussion.ObjectiveThe objective of this study is to determine the risk of concussion in male youth hockey players with preseason reports of neck pain, headaches and dizziness.DesignThis study is a secondary data analysis of a prospective cohort study examining the risk of injury associated with body checking among paediatric ice hockey players.SettingYouth ice hockey in Alberta and Quebec, Canada.ParticipantsA total of 3902 11–14 year old males from 282 teams participated.Assessment of risk factorsEach participant completed a pre-season baseline demographic and injury history questionnaire. Preseason reports of neck pain, headache or dizziness were documented on the Sport Concussion Assessment Tool.Main outcome measurementsDiagnosed concussions were recorded during the season of play via a previously validated, prospective injury surveillance system.ResultsA total of 178 concussions occurred during the studies, with 11 players sustaining two concussions. Incidence rate ratios were calculated using Poisson regression, adjusted for exposure hours, cluster by team and potential covariates. Dizziness was not a significant predictor of concussion. Individuals reporting a headache or neck pain at the start of the season were 1.48 (95% CI 1.02 to 2.14) and 1.69 (95% CI 1.16 to 2.44) times more likely to suffer a concussion during the season than those not reporting these symptoms. Individuals reporting any two of dizziness, headache and neck pain were 1.99 (95% CI 1.20 to 3.32) times more likely to sustain a concussion.ConclusionMale youth athletes reporting headache or neck pain at baseline were at an increased risk of concussion during the season. From an injury prevention perspective, baseline testing may aid in identifying individuals at a higher risk for concussion.
Effectiveness of cervical spine stabilisation techniques
Authors: Boissy P , Shrier I , Mellete J , Fecteau L , Matheson G O , Garza D , Meeuwisse W H , Segal E , Boulay J , Steele R 
Published: March 2011

BackgroundProper stabilisation of suspected unstable spine injuries is necessary to prevent (worsen) spinal cord damage. Although the lift-and-slide (L&S) technique has been shown superior to the log-roll (LR) technique to place the body on the spinal board, no studies have yet compared different techniques of manual stabilisation of the c-spine itself.ObjectiveTo compare cervical motions that occur when trained professionals perform the Head Squeeze (HS) and Trap Squeeze (TS) c-spine stabilisation techniques.DesignCross-over.Setting and participants12 experienced therapists.AssessmentHS and TS during lift-and-slide (L&S) and LR placement on spinal board, and agitated patient trying to trying to sit up (AGIT-Sit) or rotate his head (AGIT-Rot).Main outcome measurementsPeak head motion with respect to initial conditions using inertial measurement units attached to the forehead and trunk of the simulated patient. Comparisons between HS and TS with a priori minimal important difference (MID) of 5° for flexion or extension, and 3° for rotation or lateral flexion.ResultsOverall, the L&S technique was statistically superior to the LR technique. The only differences to exceed the MID were extension and rotation during LR (HS>TS). In the AGIT-Sit test scenario, differences in motion exceeded MID (HS>TS) for flexion, rotation and lateral flexion. In the AGIT-Rot scenario, differences in motion exceeded MID for rotation only (HS>TS). There was similar inter-trial variability of motion for HS and TS during L&S and LR, but significantly more variability with HS compared to TS in the agitated patient.ConclusionThe L&S is preferable to the LR when possible for minimizing unwanted c-spine motion. There is little overall difference between HS and TS in a cooperative patient. When a patient is confused and trying to move, the HS is much worse than the TS at minimizing c-spine motion.