Observation of the scapular posture is one of the most important components of the physical examination in overhead athletes. Postural asymmetry is typically considered to be associated with injuries. However, asymmetry in the overhead athlete's scapula may be normal due to the dominant use of the limb. To quantify the differences in resting scapular posture between the dominant and nondominant sides in 3 groups of healthy overhead athletes (baseball pitchers, volleyball players, and tennis players) using an electromagnetic tracking device. Cross-sectional design. University-based biomechanics laboratory. A total of 43 players participated, including 15 baseball pitchers, 15 volleyball players, and 13 tennis players. All participants were healthy college-aged men. Bilateral 3-dimensional scapular kinematics with the arm at rest were measured using an electromagnetic tracking device. Bilateral scapular position and orientation were measured. Between-groups and between-sides differences in each variable were analyzed using separate analyses of variance. In tennis players, the scapula was more protracted on the dominant side than on the nondominant side (P < .05). In all overhead athletes, the dominant-side scapula was more internally rotated (P = .001) and anteriorly tilted (P = .001) than the nondominant-side scapula was. The dominant-side scapula of the overhead athletes was more internally rotated and anteriorly tilted than the nondominant-side scapula. The dominant-side scapula of the tennis players was more protracted than that on the nondominant side. Clinicians evaluating overhead athletes need to recognize that scapular posture asymmetry in unilateral overhead athletes may be normal. Our results emphasize the importance of the baseline evaluation in this population in order to accurately assess pathologic change in bilateral scapular positions and orientations after injury.Abstract
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Few researchers have examined shoulder strength in adolescent volleyball athletes despite increasing levels of participation in this age group. To compare medial and lateral isokinetic peak torque of the rotator cuff among skill levels and between athletes with and without a history of shoulder injury. Cross-sectional design. The Human Performance Lab and Athletic Training Lab. Thirty-eight female adolescent club volleyball athletes from 10 to 15 years of age (mean = 13.02 ± 1.60 years). We measured concentric and eccentric peak torque of the medial and lateral rotators of the shoulder and calculated resultant cocking and spiking ratios based on peak torque values. Athletes at higher skill levels had higher peak torque measurements in concentric and eccentric medial and lateral rotation compared with the athletes at lower skill levels. No differences in peak torque existed between participants with or without an injury history 6 months before the study. Strength ratios did not differ across skill levels, but previously injured participants produced lower eccentric medial rotation to concentric lateral rotation ratios compared with participants without a history of injury (P = .02). At the highest skill level, previously injured participants produced lower eccentric lateral rotation to concentric medial rotation ratios compared with participants without an injury history (P = .04). Differences in medial and lateral shoulder rotator strength ratios appear to be related more to injury prevalence than to absolute strength. Shoulder dysfunction related to strength ratio deficits also may exist in adolescent female volleyball athletes. Preventive shoulder strengthening programs focused on improving eccentric strength and correcting imbalances between medial and lateral rotators may be warranted for all female adolescent volleyball athletes.Abstract
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Researchers have indicated that female soccer players may be at greater risk of concussion compared with their male counterparts. Soccer headgear is marketed for reducing head acceleration and risk of concussion. To determine the effect of sex and soccer headgear on head impact kinematics and dynamic stabilization during soccer heading. Cross-sectional design. Research laboratory. Forty-four college-aged soccer players (29 women, 15 men). Using a head impact model, participants performed 4 soccer headers under 3 headgear conditions (control, Head Blast Soccer Band, and Full90 Select Performance Headguard). Dependent variables assessed before soccer heading were head-neck anthropometrics and isometric neck muscle strength, and those assessed during soccer headers were resultant linear head acceleration, Head Injury Criteria (HIC36), and superficial neck muscle electromyography. Statistical analyses included multivariate and univariate analyses of variance with repeated measures, independent-samples t tests, appropriate follow-up analyses of variance and post hoc t tests, and Pearson product moment correlations (α = .05). Head acceleration in women was 32% and 44% greater than in men when wearing the Head Blast (21.5 g versus 16.3 g) and Full90 Select (21.8 g versus 15.2 g), respectively (P < .05). Compared with men, women exhibited 10% greater head accelerations (20.2 g versus 18.2 g) during the control condition (P = .164). Female soccer players exhibited greater head accelerations than their male counterparts when wearing headgear. Our results are important clinically because they indicate that soccer headgear may not be an appropriate head injury prevention tool for all athletes.Abstract
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Carbohydrate ingestion has recently been associated with elevated core temperature during exercise in the heat when testing for ergogenic effects. Whether the association holds when metabolic rate is controlled is unclear. Such an effect would have undesirable consequences for the safety of the athlete. To examine whether ingesting fluids containing carbohydrate contributed to an accelerated rise in core temperature and greater overall body heat production during 1 hour of exercise at 30°C when the effort was maintained at steady state. Crossover design (repeated measures) in randomized order of treatments of drinking fluids with carbohydrate and electrolytes (CHO) or flavored-water placebo with electrolytes (PLA). The beverages were identical except for the carbohydrate content: CHO = 93.7 ± 11.2 g, PLA = 0 g. Research laboratory. Nine physically fit, endurance-trained adult males. Using rectal temperature sensors, we measured core temperature during 30 minutes of rest and 60 minutes of exercise at 65% of maximal oxygen uptake (V˙o2 max) in the heat (30.6°C, 51.8% relative humidity). Participants drank equal volumes (1.6 L) of 2 beverages in aliquots 30 minutes before and every 15 minutes during exercise. Volumes were fixed to approximate sweat rates and minimize dehydration. Rectal temperature and metabolic response (V˙o2, heart rate). Peak temperature, rate of temperature increase, and metabolic responses did not differ between beverage treatments. Initial hydration status, sweat rate, and fluid replacement were also not different between trials, as planned. Ingestion of carbohydrate in fluid volumes that minimized dehydration during 1 hour of steady-state exercise at 30°C did not elicit an increase in metabolic rate or core temperature.Abstract
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Whether muscle warming protects against exercise-induced muscle damage is unknown. To determine the effect of leg immersion in warm water before stretch-shortening exercise on the time course of indirect markers of exercise-induced muscle damage. Crossover trial. Human kinetics laboratory. Eleven healthy, untrained men (age = 21.5 ± 1.7 years). Participants' legs were immersed in a water bath at 44 ± 1°C for 45 minutes. Creatine kinase changes in the blood, muscle soreness, prolonged (within 72 hours) impairment in maximal voluntary contraction force and height of drop jump, and electrically evoked muscle force at low and high stimulation frequencies at short and long muscle lengths. Leg immersion in warm water before stretch-shortening exercise reduced most of the indirect markers of exercise-induced muscle damage, including creatine kinase activity in the blood, muscle soreness, maximal voluntary contraction force, and jump height. The values for maximal voluntary contraction force and jump height, however, were higher during prewarming than for the control condition at 48 hours after stretch-shortening exercise, but this difference was only minor at other time points. Muscle prewarming did not bring about any changes in the dynamics of low-frequency fatigue, registered at either short or long muscle length, within 72 hours of stretch-shortening exercise. Leg immersion in warm water before stretch-shortening exercise reduced most of the indirect markers of exercise-induced muscle damage. However, the clinical application of muscle prewarming may be limited, because decreasing muscle damage did not necessarily lead to improved voluntary performance.Abstract
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Acute skin trauma during sport participation, resulting in partial-thickness abrasions, is common. The limited investigations focusing on the acute wound environment and dressing techniques and the subsequent lack of evidence-based standards complicate clinical wound care decisions. To examine the effects of occlusive dressings on healing of standardized, partial-thickness abrasions. Controlled, counterbalanced, repeated-measures design. University laboratory. Sixteen healthy women (n = 10) and men (n = 6). Four standardized, partial-thickness abrasions were inflicted. Film, hydrogel, and hydrocolloid occlusive dressings and no dressing (control) were applied. Participants returned on postwound days 1, 3, 5, 7, 10, and 14 for digital imaging. Wound healing time was measured by change in wound contraction (cm2) and change in wound color (chromatic red) and luminance in red, green, and blue color values. Wound contraction, color (chromatic red), and luminance. A day-by-dressing interaction was found for wound contraction, color, and luminance. Post hoc testing indicated that the film and hydrocolloid dressings produced greater wound contraction than the hydrogel and no dressing on days 7 and 10. Film, hydrogel, and hydrocolloid dressings also resulted in greater wound contraction than the control on day 14. Hydrocolloid dressings produced smaller measures of color and greater measures of luminance than no dressing on day 7. Film, hydrogel, and hydrocolloid dressings also resulted in smaller measures of color and greater measures of luminance compared with no dressing on days 10 and 14. When compared with the control (no dressing), the film, hydrogel, and hydrocolloid occlusive dressings were associated with a faster healing rate of partial-thickness abrasions across time measured by wound contraction, color, and luminance. Overall, these data indicate that occlusive dressings were more effective in healing than no dressing was.Abstract
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Metabolic syndrome is a clustering of symptoms associated with abdominal obesity that demonstrates a high risk for cardiovascular disease and type II diabetes mellitus. To evaluate football linemen in National Collegiate Athletic Association Divisions I, II, and III schools for the presence of metabolic syndrome according to the American Heart Association/National Heart, Lung, and Blood Institute criteria as well as to document other related biomarkers. Cross-sectional descriptive study. Three university locations on the first full day of football camp in early morning. Of 76 football linemen, 70 were able to provide blood samples. Height, mass, blood pressure, upper-body skinfolds, and waist circumference were measured at various stations. Two small venous samples of blood were collected and analyzed in a hospital laboratory for fasting insulin, glucose, high-density lipoprotein, total cholesterol, triglycerides, C-reactive protein, and glycosylated hemoglobin. The last station was a verbal family history for cardiovascular disease and diabetes; also, athletes filled out a nutrition attitudes questionnaire. Of the 70 athletes, 34 were identified as having metabolic syndrome according to measures of blood pressure, waist circumference, fasting glucose, high-density lipoprotein, and triglycerides. The mean total cholesterol-to-high-density lipoprotein cholesterol ratio for the group was 4.95, with 32 participants displaying values higher than 5.0. Twelve volunteers had total cholesterol levels greater than 200 mmol/L, 15 had high levels of C-reactive protein, and 9 had slightly elevated levels of glycosylated hemoglobin. Although athletes might be assumed to be protected from risks of cardiovascular disease, we found a high incidence of metabolic syndrome and other associated adverse biomarkers for heart disease in collegiate football linemen. Early screening, awareness, and intervention may have favorable effects on the overall health outcomes of football linemen.Abstract
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As health care providers, certified athletic trainers (ATs) should be role models for healthy behaviors. To analyze the self-reported health and fitness habits of ATs. A cross-sectional, cluster random sample. Online questionnaire. Of a sampling frame of 1000 potential participants, 275 ATs completed the questionnaire. Health habits and activity were based on a typical 7-day week. A total of 41% of the participants met the exercise recommendations of the American College of Sports Medicine; 7% reported being sedentary. Differences were noted between the sexes for fitness habits (P < .035) and composite health score (P < .001). None of the ATs reported meeting the Daily Reference Intake for all 5 food groups. Seven percent of female ATs consumed more alcohol than recommended, compared with 2% of males. However, 80% of males and 93% of females reported consuming 5 or fewer drinks per week. Only 0.8% reported currently smoking. This sample of ATs had better health and fitness habits than the general population but did not meet professional recommendations set forth by the American College of Sports Medicine or the United States Department of Agriculture. Thus, these ATs were not ideal role models in demonstrating healthy behaviors.Abstract
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Although more than 7 million athletes participate in high school sports in the United States, to date no nationally representative studies of rare injuries and conditions (RICs) exist. Rare injuries and conditions include eye injuries, dental injuries, neck and cervical injuries, and dehydration and heat illnesses. To describe the epidemiology of RICs sustained by high school athletes during the 2005–2006 and 2006–2007 school years. Prospective cohort study. A nationally representative sample of 100 US high schools using an injury surveillance system, High School Reporting Information Online. Athletes participating in football, boys' soccer, girls' soccer, volleyball, boys' basketball, girls' basketball, wrestling, baseball, or softball at one of the 100 participating high schools. We reviewed all RICs to calculate injury rates and to identify potential risk factors and preventive measures. A total of 321 RICs were sustained during 3 550 141 athlete-exposures (AEs), for an injury rate of 9.04 RICs per 100 000 AEs. This represents an estimated 84 223 RICs sustained nationally. The RICs accounted for 3.5% of all high school athletes' injuries. The most common diagnoses were neck and cervical injuries (62.0%, n = 199) and dehydration and heat illnesses (18.7%, n = 60). Football had the highest RIC rate per 100 000 AEs (21.2), followed by wrestling (15.2) and baseball (7.60). The RICs occurred at a higher rate in boys (12.4) than in girls (2.51) (rate ratio = 4.93; 95% confidence interval = 3.39, 7.18). The majority of RICs (67.3%, n = 216) permitted athletes to return to play within 1 week of diagnosis. The RIC injury rates varied by sport and sex and represented almost 100 000 potentially preventable injuries to high school athletes. Because of the potentially serious consequences, future researchers must develop and implement more effective preventive measures to aid certified athletic trainers in decreasing the RIC incidence among high school athletes.Abstract
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To provide background information on methodologic factors that influence and add variance to endocrine outcome measurements. Our intent is to aid and improve the quality of exercise science and sports medicine research endeavors of investigators inexperienced in endocrinology. Numerous methodologic factors influence human endocrine (hormonal) measurements and, consequently, can dramatically compromise the accuracy and validity of exercise and sports medicine research. These factors can be categorized into those that are biologic and those that are procedural-analytic in nature. Researchers should design their studies to monitor, control, and adjust for the biologic and procedural-analytic factors discussed within this paper. By doing so, they will find less variance in their hormonal outcomes and thereby will increase the validity of their physiologic data. These actions can assist the researcher in the interpretation and understanding of endocrine data and, in turn, make their research more scientifically sound.Abstract
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To present recommendations for the prevention, recognition, and treatment of environmental cold injuries. Individuals engaged in sport-related or work-related physical activity in cold, wet, or windy conditions are at risk for environmental cold injuries. An understanding of the physiology and pathophysiology, risk management, recognition, and immediate care of environmental cold injuries is an essential skill for certified athletic trainers and other health care providers working with individuals at risk. These recommendations are intended to provide certified athletic trainers and others participating in athletic health care with the specific knowledge and problem-solving skills needed to address environmental cold injuries. Each recommendation has been graded (A, B, or C) according to the Strength of Recommendation Taxonomy criterion scale.Abstract
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Reliability and Validity of the Functional Assessment of Neurocognition in Sport (FANS): A Paradigm Shift in Post-Concussion Return-to-Sport Decision-Making
Driving After Concussion: Clinical Measures Associated with Post-concussion
The role of shoulder posture in pitching mechanics and injury risk in high school baseball pitchers
Corticospinal Excitability during Standing and Its Association with Postural Control Following Acute Lateral Ankle Sprain.
The socio-economic cost of anterior cruciate ligament injuries and lateral ankle sprains in amateur football and basketball.
JAT eISSN: 1938-162X
JAT ISSN: 1062-6050
ATEJ ISSN: 1947-380X