ISSN:1050-642X    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveThere is widespread public concern about fairness in sports. Blood doping undermines fairness and places athletes' health at risk. The purpose of this study was to examine the prevalence of abnormal hematologic profiles in elite cross-country skiers, which may indicate a high probability of blood doping.Setting and ParticipantsSamples were obtained as part of routine International Ski Federation blood testing procedures from participants at the World Ski Championships. Sixty-eight percent of all skiers and 92% of those finishing in the top 10 places were tested.Main Outcome MeasuresUsing flow cytometry, we analyzed erythrocyte and reticulocyte indices. Reference values were from the 1989 Nordic Ski World Championships data set and the International Olympic Committee Erythropoietin 2000 project.ResultsOf the skiers tested and finishing within the top 50 places in the competitions, 17% had “highly abnormal” hematologic profiles, 19% had “abnormal” values, and 64% were normal. Fifty percent of medal winners and 33% of those finishing from 4th to 10th place had highly abnormal hematologic profiles. In contrast, only 3% of skiers finishing from 41st to 50th place had highly abnormal values.ConclusionsThese data suggest that blood doping is both prevalent and effective in cross-country ski racing, and current testing programs for blood doping are ineffective. It is unlikely that blood doping is less common in other endurance sports. Ramifications of doping affect not only elite athletes who may feel compelled to risk their health but also the general population, particularly young people.

ISSN:1050-642X    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveTo 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.DesignRandomized, double-blinded study with a 4-day treatment protocol.SettingUniversity-based sports medicine clinic.ParticipantsSixteen sedentary female university studentsInterventionsAll subjects performed 300 maximal voluntary eccentric contractions (30 sets of 10 repetitions per minute) of their nondominant leg (110 to 35° of knee flexion) at a slow speed (30° 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 MeasuresDependent 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).ResultsRepeated-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).ConclusionsThe 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.

ISSN:1050-642X    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveTo determine the effectiveness of magnetic resonance imaging in identifying shoulder pathology in patients with primary traumatic dislocation of the shoulder and to compare these findings with findings at the time of arthroscopic surgery.DesignCorrelation between arthroscopy and magnetic resonance imaging.PatientsSixteen patients, aged 18 to 30 years, who were randomized to the surgical arm of a study comparing the effectiveness of immediate arthroscopic surgery with immobilization and rehabilitation for primary traumatic anterior dislocation of the shoulder, were included in this study.InterventionsEach patient underwent magnetic resonance imaging and a videotaped “tour” of the shoulder prior to any surgical intervention.Main Outcome MeasureMagnetic resonance scans and videotapes were reviewed for the presence or absence of abnormalities in 8 features of the shoulder, and concordant and discordant findings were evaluated.ResultsThere was moderate correlation for superior labral lesions (&kgr; = 0.60) and fair agreement for rotator cuff tear (&kgr; = 0.355). When the joint capsule was assessed, there was only fair agreement for both the presence of an abnormality (&kgr; = 0.310) and redundancy and tear (&kgr; = 0.394). Both methods were sensitive for the detection of Hill-Sachs lesions (&kgr; = 1.0), although there was only moderate agreement (&kgr; = 0.44) on estimation of size. There was perfect agreement for the detection of Bankart lesions or equivalent capsulolabral disruption (&kgr; = 1.0).ConclusionsMagnetic resonance imaging can be considered a valuable tool for the detection of Hill-Sachs and Bankart lesions associated with primary traumatic anterior dislocations of the shoulder. Its ability to detect other pathologic lesions, however, is limited.

ISSN:1050-642X    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

BackgroundThe hip joint is becoming increasingly recognized as a source of groin pain and, in the authors' experience, buttock and low back pain.ObjectivesTo determine the range of pathologic diagnoses, clinical presentation, and the correlation between magnetic resonance arthrographic, ultrasonographic, and arthroscopic findings in the hip joint.MethodsWe prospectively studied 25 consecutive hip arthroscopies to determine the range of pathologic diagnoses, clinical presentation, and the correlation between magnetic resonance arthrographic, ultrasonographic, and arthroscopic findings.ResultsAll of the hips arthroscoped had pathology. Back pain and hip pain were the 2 most common presentations. The only consistently positive clinical test result was a restricted and painful hip quadrant compared with the contralateral hip. Of the 17 patients whose flexion, abduction, external rotation (FABER) test results were reported at the time of examination, 15 (88%) were positive, and 2 (12%) negative. Plain radiographs were normal in all patients. All but 1 patient underwent magnetic resonance arthrography. Although specificity of 100% was achieved in our study, the sensitivity was significantly lower, with a relatively high number of false negatives. Hip arthroscopy proved the definitive diagnostic procedure for intraarticular pathology.ConclusionsHip pathology, particularly labral pathology, may be more common than has been previously recognized. In those patients with chronic groin and low back pain, a high index of suspicion should be maintained. Clinical signs of a painful, restricted hip quadrant and a positive FABER test result should suggest magnetic resonance arthrography in the first instance, but a negative magnetic resonance image should not preclude hip arthroscopy if there is high clinical suspicion of hip joint pathology.

ISSN:1050-642X    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveStrenuous physical activity, such as military training, is known to demand a high degree of physical performance and to cause overuse injuries. However, the exact relation between injury incidence and physical fitness level and the influence of military training on measures of functional performance, such as intermittent endurance capacity and maximal jump performance, are not fully described.MethodsA total of 330 military conscripts were prospectively followed during military basic training. They were divided into 4 self-assessed physical fitness level groups (well trained, trained, less trained, and untrained) and underwent physical performance tests together with registration of injury incidence.ResultsTwelve weeks of military basic training was found to result in an overall injury rate of 28%, with an inverse relation between physical fitness level and incidence of overuse injury (P< 0.0001). Furthermore a fourfold higher injury rate was observed in the previously untrained soldiers compared with the well-trained soldiers. An increase in intermittent endurance capacity (20-m intermittent shuttle run test) was seen in all groups, (13 to 62%,P< 0.05), whereas only the previously untrained group of soldiers improved in aerobic capacity (8 and 16%,P< 0.05; maximal oxygen uptake and Coopers 12-minute running test). Maximal jump performance, both with and without backpack loading (15 kg), decreased (5 to 13%,P< 0.05) in 93% of the soldiers despite weight loss.ConclusionsMilitary basic training has a positive effect on intermittent endurance capacity but a detrimental effect on jump performance. Furthermore, low levels of physical fitness are strongly associated with proneness toward overuse injury development in soldiers going through intense training.

ISSN:1050-642X    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveTo understand the estimation of both the effective dose and the risk estimate associated with diagnostic ionizing radiation in sports medicine and to appreciate strategies by which this radiation exposure may be minimized.DesignObservational study.SettingSports medicine practice.PatientsA theoretical patient, athlete X (male, aged 20–29 years, 80 kg), was used to illustrate how the effective dose and the corresponding risk estimate are calculated for various common sports medicine investigations. Doses and risk estimates for female and pediatric athletes also are discussed.Main Outcome MeasuresThe effective dose and corresponding risk estimate associated with common sports medicine investigations.ResultsComputed tomography and radiographic examinations of the extremities have significantly lower effective doses than investigations about the trunk region. Bone scanning and computed tomography have a significantly higher effective dose than radiography. The risk estimates associated with the low doses used in diagnostic ionizing radiation procedures are extrapolated from epidemiologic studies on exposures to high doses of radiation, and several uncertainties exist in this estimation. Notwithstanding this, the responsible clinician should be aware of both the effective doses and the risk estimates that are associated with the more common investigations. The principles of justification and optimization for these investigations will help guide clinicians to reduce radiation exposure without compromising the management of their patients.ConclusionsCertain investigations have a greater effective dose and risk estimate than others. Elite athletes may potentially undergo numerous investigations in their career. An athlete radiation record may be useful to better manage this exposure.

ISSN:1050-642X    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveTo investigate change in serum sodium concentration and its potential causes during a cold weather ultradistance race.DesignDescriptive research.SettingA 100-mile (161-km) race over a snow-packed course in the Alaskan wilderness. Athletes competed in 1 of 3 divisions: foot, bike, or ski.ParticipantsTwenty athletes (11 runners, 6 cyclists, 3 skiers) volunteered for the study.InterventionsNone.Main Outcome MeasuresSubjects were weighed and had blood drawn for hematocrit, serum sodium, serum aldosterone, and plasma arginine vasopressin concentrations pre- and postrace. Fluid and sodium intake were determined by race dietary analysis.ResultsSerum sodium concentration decreased significantly prerace (140.8 ± 1.2 mmol/L) to postrace (138.4 ± 2.2 mmol/L), although no athletes were classified as hyponatremic. Mean weight loss was significant during the race (−1.2 kg), although 1 athlete maintained his weight, and 3 athletes gained small amounts of weight (0.2 kg, 0.2 kg, and 0.5 kg, respectively). Hematocrit decreased significantly prerace (42.2 ± 3.5) to postrace (40.3 ± 4.1). Plasma arginine vasopressin and serum aldosterone increased significantly during the race (2.6 ± 0.7 to 6.0 ± 4.6 pg/mL and 5.1 ± 2.6 to 40.8 ± 25.1 ng/dL, respectively). Fluid consumption was 300 ± 100 mL/h, and sodium intake was 310 ± 187 mg/h.ConclusionsDecreased serum sodium concentration after a cold weather ultradistance race was due to fluid overload caused by excessive fluid consumption. Current recommendations that ultradistance athletes consume 500 to 1000 mL/h may be too high for athletes competing in the extreme cold.

ISSN:1050-642X    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveTo review randomized controlled trials evaluating the effectiveness of therapeutic exercise and orthopedic manual therapy for the treatment of impingement syndrome.Data SourceReports up to October 2002 were located from MEDLINE, the Cochrane Database of Systematic Reviews, the Physiotherapy Evidence Database (PEDro), the TRIP database, and the Cumulative Index to Nursing & Allied Health Literature (CINAHL) using “shoulder” and “clinical trial”/“randomized controlled trial” as search terms.Study SelectionStudies were included if (1) they were a randomized controlled trial; (2) they were related to impingement syndrome, rotator cuff tendinitis, or bursitis; (3) one of the treatments included therapeutic exercise or manual therapy.Data ExtractionTwo independent observers reviewed the methodological quality of the studies using an assessment tool developed by the Cochrane Musculoskeletal Injuries Group. Differences were resolved by consensus.Data SynthesisSeven trials met our inclusion criteria. After consensus, the mean methodological score for all studies was 13.9 ± 2.4 (of 24). Four studies of 7, including the 3 trials with the best methodological score (67%), suggested some benefit of therapeutic exercise or manual therapy compared with other treatments such as acromioplasty, placebo, or no intervention.ConclusionsThere is limited evidence to support the efficacy of therapeutic exercise and manual therapy to treat impingement syndrome. More methodologically sound studies are needed to further evaluate these interventions.

ISSN:1050-642X    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:1050-642X    

出版商:OVID    

年代:2003

数据来源: OVID