ISSN:1050-642X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

ObjectiveThe purpose of this pilot study was to document the nature and temporal profile of the clinical symptoms of acute sport-related concussion.DesignProspective cohort studyPatient PopulationA total of 303 elite Australian football players participating in a national competition during a single season.Outcome MeasuresNumber and duration of symptoms, digit symbol substitution test (DSST) scores, time of return to play post injury.ResultsA total of 23 concussions were recorded over the course of the 20-week football season. No catastrophic head injuries occurred. Headache was the most common symptom and the most persistent, with 40% of players reporting headache symptoms lasting more than 15 minutes. Ten of the players (43%) returned to sport on the day of the injury with the remainder resuming play within 2 weeks. A low likelihood of return to play on the day of injury was found where 3 or more symptoms were present or where the symptoms lasted more than 15 minutes. These findings were significantly correlated with poor DSST performance.ConclusionsThis pilot study suggests that both the number of postconcussive symptoms and their duration may be used as a measure of injury severity and a guide for return to play.

ISSN:1050-642X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

ObjectiveThe purpose of this study was to determine if a preseason measurement of balance while in a unilateral stance could predict susceptibility to ankle injury in a cohort of high school basketball players. Predicting risk for ankle injury could be important in helping to reduce the risk of these injuries and furthermore save health care costs.DesignCohort study.SettingData were collected at five high schools during the first 2 weeks of the 1997–1998 and 1998–1999 basketball seasons.Subjects210 (119 male, age = 16.1 ± 1.1 yr; height = 182.98 ± 7.4 cm; weight = 76.4 ± 10.9 kg; and 91 female, age = 16.3 ± 1.3 yr; height = 170.9 ± 7.8 cm; weight = 63.4 ± 8.4 kg) high school basketball players who did not sustain a time loss ankle or knee injury within the previous 12 months served as subjects. Subjects did not use prophylactic ankle taping or bracing during the season.Assessment of Risk FactorsBalance was quantified from postural sway scores measured while subjects performed unilateral balance tests with eyes both open and closed. Logistic regression analysis was carried out to determine if gender, dominant leg, and balance scores were related to ankle sprain injuries. In addition, Fischer's exact test was used to determine if the rate of ankle injuries was the same whether the subject had poor, average, or good balance. Balance was assessed by measuring postural sway with the NeuroCom New Balance Master version 6.0 (NeuroCom International, Clackamas, OR, U.S.A.). Testing to determine postural sway consisted of having subjects stand on one leg for three trials of 10 seconds with their eyes open, then repeated with their eyes closed. Subjects then underwent the same assessment while standing on the other leg. Postural sway was defined as the average degrees of sway per second (°S/S) for the 12 trials producing a compilation (COMP) score.Outcome MeasuresAnkle injury resulting in missed participation.ResultsSubjects who sustained ankle sprains had a preseason COMP score of 2.01 ± 0.32 (Mean ± SD), while athletes who did not sustain ankle injuries had a score of 1.74 ± 0.31. Higher postural sway scores corresponded to increased ankle sprain injury rates (p = 0.001). Subjects who demonstrated poor balance (high sway scores) had nearly seven times as many ankle sprains as subjects who had good balance (low sway scores) (p = 0.0002.)ConclusionIn this cohort of high school basketball players, preseason balance measurement (postural sway) served as a predictor of ankle sprain susceptibility.

ISSN:1050-642X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Objectives1) To evaluate strength changes in the hindfoot invertor and evertor muscle groups of athletes training and competing primarily in the counterclockwise direction on an indoor, unbanked track, and 2) to observe injuries occurring in these same runners over the course of an indoor season.DesignProspective observational study.SettingFowler-Kennedy Sport Medicine Clinic, The University of Western Ontario, London, Ontario.ParticipantsA convenience sample of 25 intercollegiate, long sprinters (200–600 m) and middle distance runners (800–3,000 m) competing and training with the 1995–1996 University of Western Ontario Track and Field team.Main Outcome MeasuresA standardized protocol using the Cybex 6000 isokinetic dynamometer was used to measure peak torques of the hindfoot invertor and evertor muscle groups of both limbs using concentric and eccentric contractions performed at angular velocities of 60, 120, and 300°/sec. Changes in peak torques between the preseason and postseason values were calculated and compared using a repeated measures analysis of variance test. Injury reports were collected by student athletic trainers and in the Sport Medicine and Physiotherapy clinic.ResultsPrimary analysis indicated that the left (inside limb) invertors increased in strength significantly more than the right (outside limb) invertors (p = 0.01), while the right evertors increased in strength significantly more than the left evertors (p = 0.04). A high incidence of lower extremity injury (68%) occurred in this sample of runners, corresponding to an injury rate of 0.75 injuries per 100 person-hours of sport exposure. Although sample size was limited, secondary analysis indicated that strength changes were not significantly different for injured (n = 17) and uninjured (n = 8) runners (p > 0.05).ConclusionsThe observed small, but statistically significant, asymmetrical changes in strength of the hindfoot invertor and evertor muscle groups can best be described as a training effect. Altered biomechanics proposed to occur in the stance foot while running on the curve of the track are discussed in relation to the observed strength imbalance. A causal link between strength changes and lower extremity injuries cannot be inferred from this study, but suggestions for further research are made.

ISSN:1050-642X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

ObjectiveTo use two commonly accepted measurement techniques to determine whether intense swimming exercise altered scapular position in male high school swimmers. Scapular position differences between dominant and nondominant shoulders were also investigated.DesignA pilot study on 10 asymptomatic male volunteers established the reliability of the scapular position measurement techniques described by DiVeta and Kibler (intratester intraclass correlation coefficients 0.86–0.98). Scapular position was prospectively recorded before and after swimming practice just prior to tapering for championship competition.ParticipantsTwenty male high school swimmers from two local teams, ages 13 to 18 years.InterventionsSubjects completed their usual 2-hour swimming practice at the peak of their training intensity.Main Outcome MeasuresChange in scapular position preexercise versus postexercise.ResultsScapular position did not change preexercise to postexercise for either the DiVeta (22.2 ± 1.4 to 22.3 ± 1.5 cm, p = 0.96) or Kibler (9.2 ± 1.4 to 9.4 ± 1.3 cm, p = 1.00) measures. Nondominant preexercise scapular position was generally more medial and moved laterally with exercise, becoming roughly equivalent to the dominant shoulder.ConclusionThe DiVeta and Kibler scapular position measurement techniques are acceptably reliable. However these techniques generally failed to demonstrate significant changes in scapular position after intense swimming exercise in the study population. Nondominant side scapulae typically moved laterally postexercise. These findings and implications are discussed.

ISSN:1050-642X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

ObjectiveTo examine the association between physical activity-related injuries and participation in walking versus running.DesignNested case-control study.SettingCooper Clinic Preventive Medicine Center, Dallas, Texas.Participants5,327 men and women undergoing exams between 1987 and 1995 and completing follow-up health history questionnaires in 1990 or 1995. Participants were classified as those reporting regular participation in walking or jogging/running at baseline. Those reporting both or neither activity were excluded from the study (n = 1404). Cases (698 men, 169 women) were those reporting physical activity-related injuries requiring physician visits in the previous year on the follow-up questionnaire. Controls (2,358 men, 698 women) were randomly selected from the remaining population.Main Outcome MeasuresLogistic regression was used to examine the risk of injury in walkers versus runners and risk of injury by exercise dose while considering age, body mass index, previous injury, and strength training.ResultsThere was a significantly lower risk of injury for walkers compared with runners in young (<45 years old) (odds ratio [OR] = 0.75, 95% confidence interval [CI] = 0.58–0.97) and older (≥45 years) men (OR = 0.64, 95% CI = 0.49–0.82), and a nonsignificantly lower risk among young (OR = 0.73, 95% CI = 0.39–1.37) and older women (OR = 0.72, 95% CI = 0.38–1.35). There was no effect of greater amounts of walking on injuries for either gender; however, there was a higher injury risk associated with running 15–30 min/day (OR = 1.36, 95% CI = 1.07–1.73) and 30+ min/day (OR = 1.52, 95% CI = 1.14–2.04) compared with <15 min/day among men, but not among women.ConclusionsThis low risk of musculoskeletal injury suggests that participation in walking can be safely recommended as a way to improve health and fitness.

ISSN:1050-642X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Objectives1) To evaluate the test–retest reliability of lower extremity functional instability measures involving testing situations of varying complexity, and 2) To evaluate the interrelationships among performances observed during these tests and a maximal single-limb forward hop for distance.DesignA repeated measures design, repeated on two occasions.SettingPostural control laboratory.ParticipantsThirty young healthy subjects (23.5 ± 2.0 years).Main Outcome MeasuresSubjects performed single-limb standing balance and forward hop tests on two occasions completed within 1 week and at least 24 hours apart. Standing balance was assessed using a force platform and the following four progressively complex test situations: 1) standing on the stable platform with eyes open, 2) standing on a foam mat placed over the platform with eyes open, 3) standing on the stable platform with eyes closed, and 4) standing on the stable platform after landing from a maximal single-limb forward hop.Results and ConclusionsIntraclass correlation coefficients were moderate to excellent (0.41 to 0.91) suggesting that the standing balance tests are appropriate for distinguishing among group performances. Standard errors of measurement and associated 95% confidence intervals suggested that a change in an individual's standing balance performance of approximately 10–30% would be necessary in order to confidently state that a true change had occurred. Stronger relationships were observed between hop distance and standing balance tests performed with eyes closed (r= −0.63, p < 0.001) and after landing from a maximal hop (r= −0.53, p = 0.003), suggesting that tests that challenge postural control to a greater extent are more representative of functional performance.

ISSN:1050-642X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

ObjectiveTo test whether the association between blood groups and Achilles tendon rupture (ATR) reported in some Scandinavian countries and in Hungary was present in our region.MethodsWe studied 78 patients treated at Aberdeen Royal Infirmary from 1990 to 1996, and compared their distribution of ABO blood groups with that found in 24,501 blood donors typed at the Blood Transfusion Centre during the same period.ResultsOverall, 47 of 78 (60%) of patients with an Achilles tendon rupture belonged to blood group O, compared with 51% of the population as a whole. Only 22 (28%) of the Achilles tendon rupture patients belonged to blood group A, whereas 35% of the general population were members of this group (NS). The A/O ratio was 0.47 for the tendon rupture patients, compared with 0.68 for the general population (NS).ConclusionsWe could not demonstrate any significant association between the proportions of ABO blood groups and ATR in the Grampian Region of Scotland. The findings in other studies could be due to peculiarities in the distribution of the ABO groups in genetically segregated populations.

ISSN:1050-642X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

ObjectiveTo study fluid and sodium balance during overnight recovery following an ultradistance triathlon in hyponatremic athletes compared with normonatremic controls.Case Control StudyProspective descriptive study.Setting1997 New Zealand Ironman Triathlon (3.8 Km swim, 180 Km cycle, 42.2 Km run).ParticipantsSeven athletes (“subjects”) hospitalized with hyponatremia (median sodium [Na] = 128 mmol L−1). Data were compared with measurements from 11 normonatremic race finishers (“controls”) (median sodium = 141 mmol L−1).InterventionsNone.Main Outcome MeasuresAthletes were weighed prior to, immediately after, and on the morning after, the race. Blood was drawn for sodium, hemoglobin, and hematocrit immediately after the race and the following morning. Plasma concentrations of arginine-vasopressin (AVP) were also measured post race.ResultsSubjects were significantly smaller than controls (62.5 vs. 72.0 Kg) and lost less weight during the race than controls (median −0.5% vs. −3.9%, p = 0.002) but more weight than controls during recovery (−4.4% vs. −0.8%, p = 0.002). Subjects excreted a median fluid excess during recovery (1,346 ml); controls had a median fluid deficit (521 ml) (p = 0.009). Estimated median sodium deficit was the same in subjects and controls (88 vs. 38 mmol L−1, p = 0.25). Median AVP was significantly lower in subjects than in controls. Plasma volume fell during recovery in subjects (−5.9%, p = 0.016) but rose in controls (0.76%, p = NS).ConclusionsTriathletes with symptomatic hyponatremia following very prolonged exercise have abnormal fluid retention including an increased extracellular volume, but without evidence for large sodium losses. Such fluid retention is not associated with elevated plasma AVP concentrations.

ISSN:1050-642X    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

ObjectiveTo elicit a criterion elevation (>10%) in resting heart rate (HR) with training overstress, and subsequently test the hypothesis that such “reversed bradycardia” (RB) negatively affects running performance.DesignProspective before-and-after intervention with a comparison group.SettingGeneral community.Participants21 healthy male marathon runners.InterventionVoluntary doubling of training miles on 14 consecutive days.Main Outcome MeasuresLeft ventricular (LV) function by echocardiography, HR, and plasma epinephrine (PE) at rest and during submaximal exercise, and 15 km road run performance.ResultsTwo days after the training overstress, 12 runners met the criterion (RB group), showing an average elevation in resting HR of 16% (range: 11 to 23%). The RB group also exhibited hyperkinetic LV shortening (p < 0.05), elevated exercise HR (p < 0.001), increased PE at rest and during exercise (p < 0.05), and reduced 15 km performance (p < 0.05). The other nine runners who maintained a stable resting HR during the intervention showed no significant outcome changes.ConclusionsIn addition to muscular overuse, heightened sympathetic drive likely contributed to the observed reversal of bradycardia. The development of this stress-related cardiac perturbation was associated with a decrement in running performance, confirming the hypothesis.

ISSN:1050-642X    

出版商:OVID    

年代:2000

数据来源: OVID