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Context: Increased pitch volume and altered glenohumeral (GH) and hip range of motion (ROM) and strength contribute to injury risk in baseball pitchers. Although these factors affect one another, whether they are related is unknown. Objective: To examine relationships among cumulative and seasonal pitch volume, ROM, and strength of the GH and hip joints in youth baseball pitchers. Design: Cross-sectional study. Setting: Baseball practice facilities. Patients or Other Participants: A total of 28 healthy baseball pitchers (age = 13.9 ± 2.9 years). Main Outcome Measure(s): A demographic and pitching questionnaire was used to quantify pitch volume. Glenohumeral internal-rotation (IR) and external-rotation (ER) ROM and strength of the throwing arm; total arc of motion (IR + ER ROM); and bilateral hip IR, ER, and total arc of motion ROM and strength in IR, ER, and abduction were measured. A goniometer was used to assess ROM; a handheld dynamometer, to assess strength. Frequency analyses and bivariate correlations (age covariate) described data and identified relationships. Results: Correlations between years of competitive play and increased strength in lead-leg hip IR (r =0.52, P = .02) and abduction (r=0.48, P=.04) and stance-leg hip IR (r=0.45, P= .05) were fair to good. The number of months played in the last year had a fair correlation with decreased GH IR strength (r = -0.39, P = .04) and increased stance-leg hip IR strength (r = 0.44, P = .05). Limited pitch time had a fair correlation with increased GH ER ROM (r = 0.40, P = .04) and an excellent correlation with increased lead-leg hip IR ROM (r = 0.79, P < .001). Increased innings pitched per game had a fair to good correlation with decreased GH IR strength (r =-0.41, P = .04) and stance-leg hip ER ROM (r =-0.53, P = .03). More pitches per game had a fair to good correlation with increased GH ER ROM (r=0.44, P=.05) and decreased stance-leg hip ER ROM (r =-0.62, P = .008). Conclusions: The significant relationships identified in this study suggest the need to further examine youth and adolescent cumulative and seasonal pitch guidelines. [ABSTRACT FROM AUTHOR]

Context: Spinal axial rotation is required for many functional and sporting activities. Eighty percent of axial rotation occurs in the thoracic spine. Existing measures of thoracic spine rotation commonly involve laboratory equipment, use a seated position, and include lumbar motion. A simple performance-based outcome measure would allow clinicians to evaluate isolated thoracic spine rotation. Currently, no valid measure exists. Objective: To explore the criterion and concurrent validity of a digital inclinometer (DI) and iPhone Clinometer app (iPhone) for measuring thoracic spine rotation using the heel-sit position. Design: Controlled laboratory study. Setting: University laboratory. Patients or Other Participants: A total of 23 asymptomatic healthy participants (14 men, 9 women; age = 25.82 ± 4.28 years, height = 170.26 ± 8.01 cm, mass = 67.50 ± 9.46 kg, body mass index = 23.26 ± 2.79) were recruited from a student population. Main Outcome Measure(s): We took DI and iPhone measurements of thoracic spine rotation in the heel-sit position concurrently with dual-motion analysis (laboratory measure) and ultrasound imaging of the underlying bony tissue motion (reference standard). To determine the criterion and concurrent validity, we used the Pearson product moment correlation coefficient (r, 2 tailed) and Bland-Altman plots. Results: The DI (r = 0.88, P < .001) and iPhone (r = 0.88, P < .001) demonstrated strong criterion validity. Both also had strong concurrent validity (r = 0.98, P < .001). Bland-Altman plots illustrated mean differences of 5.82° (95% confidence interval [CI] = 20.37°, -8.73°) and 4.94° (95% CI = 19.23°, -9.35°) between the DI and iPhone, respectively, and the reference standard and 0.87° (95% CI = 6.79°, -5.05°) between the DI and iPhone. Conclusions: The DI and iPhone provided valid measures of thoracic spine rotation in the heel-sit position. Both can be used in clinical practice to assess thoracic spine rotation, which may be valuable when evaluating thoracic dysfunction. [ABSTRACT FROM AUTHOR]

Context: The ability to generate, absorb, and transmit forces through the proximal segments of the pelvis, spine, and trunk has been proposed to influence sport performance, yet traditional training techniques targeting the proximal segments have had limited success improving sport-specific performance. Objective: To investigate the effects of a traditional endurance- training program and a sport-specific power-training program targeting the muscles that support the proximal segments and throwing velocity. Design: Randomized controlled clinical trial. Setting: University research laboratory and gymnasium. Patients or Other Participants: A total of 46 (age = 20 ± 1.3 years, height = 175.7 ± 8.7 cm) healthy National Collegiate Athletic Association Division III female softball (n = 17) and male baseball (n = 29) players. Intervention(s): Blocked stratification for sex and position was used to randomly assign participants to 1 of 2 training groups for 7 weeks: a traditional endurance-training group (ET group; n = 21) or a power-stability-training group (PS group; n = 25). Mean Outcome Measure(s): The change score in peak throwing velocity (km/h) normalized for body weight (BW; kilograms) and change score in tests that challenge the muscles of the proximal segments normalized for BW (kilograms). We used 2-tailed independent-samples t tests to compare differences between the change scores. Results: The peak throwing velocity (ET group = 0.01 ± 0.1 km/h/kg of BW, PS group = 0.08 ± 0.03 km/h/kg of BW; P < .001) and muscle power outputs for the chop (ET group = 0.22 ± 0.91 W/kg of BW, PS group = 1.3 ± 0.91 W/kg of BW; P < .001) and lift (ET group = 0.59 ± 0.67 W/kg of BW, PS group = 1.4 ± 0.87 W/kg of BW; P < .001) tests were higher at postintervention in the PT than in the ET group. Conclusions: An improvement in throwing velocity occurred simultaneously with measures of muscular endurance and power after a sport-specific training regimen targeting the proximal segments. [ABSTRACT FROM AUTHOR]

Context: As evidence-based practice (EBP) becomes a necessity in athletic training, Web-based modules have been developed and made available to the National Athletic Trainers' Association membership as a mechanism to educate athletic trainers (ATs) on concepts of EBP. Objective: To assess the effect of an educational intervention on enhancing knowledge of EBP among ATs. Design: Randomized controlled trial. Setting: Web-based modules and knowledge assessment. Patients or Other Participants: A total of 164 of 473 ATs (34.7% response rate), including professional athletic training students, graduate students, clinical preceptors, educators, and clinicians, were randomized into a control group (40 men, 42 women) or experimental group (33 men, 49 women). Intervention(s): Ten Web-based modules were developed that covered concepts involved in the EBP process. Both groups completed the Evidence-Based Practice Knowledge Assessment before and after the intervention phase. During the intervention phase, the experimental group had access to the Web-based modules for 4 weeks, whereas the control group had no direct responsibilities for the investigation. The knowledge assessment consisted of 60 multiple choice questions pertaining to concepts presented in the 10 modules. Test-retest reliability was determined to be good (intraclass correlation coefficient [2,1] = 0.726, 95% confidence interval = 0.605, 0.814). Main Outcome Measure(s): Independent variables consisted of group (control, experimental) and time (preassessment, postassessment). Knowledge scores were tabulated by awarding 1 point for each correct answer (maximum = 60). Between-group and within-group differences were calculated using a 2 3 2 repeated-measures analysis of variance (P ≤ .05), post hoc t tests, and Hedges g effect size with 95% confidence intervals. Results: We found a group 3 time interaction (F1,162 = 26.29, P < .001). No differences were identified between the control (30.12 ± 5.73) and experimental (30.65 ± 5.93) groups during the preassessment (t162 = 0.58, P = .84). The experimental group (36.35 6 8.58) obtained higher scores on the postassessment than the control group (30.99 ± 6.33; t162 = 4.55, P = .01). No differences were identified among time instances within the control group (t81 =1.77, P=.08); however, the experimental group obtained higher scores on the postassessment than the preassessment (t81 = 7.07, P < .001). Conclusions: An educational intervention consisting of 10 Web-based modules was an effective mechanism to increase knowledge of foundational EBP concepts among ATs. However, it is not known whether ATs are integrating EBP into daily clinical practice. Researchers should determine whether increased knowledge of EBP affects the daily clinical decision making of ATs. [ABSTRACT FROM AUTHOR]

Context: Athletic trainers recommend and use a multitude of rehydration (REHY) methods with their patients. The REHY modality that most effectively facilitates recovery is unknown. Objective: To compare 5 common REHY methods for thermoregulatory and stress hormone recovery after exercise dehydration (EXDE) in trained participants. Design: Randomized, cross-over, controlled study. Patients or Other Participants: Twelve physically active, non-heat-acclimatized men (age = 23 ± 4 years, height = 180 ± 6 cm, mass = 81.3 ± 3.7 kg, Vo2max = 56.9 ± 4.4 mL⋅min-1⋅kg-1, body fat = 7.9% 6 3%) participated. Intervention(s): Participants completed 20-hour fluid restriction and 2-hour EXDE; they then received no fluid (NF) or REHY (half-normal saline) via ad libitum (AL), oral (OR), intravenous (IV), or combination IV and OR (IV + OR) routes for 30 minutes; and then were observed for another 30 minutes. Main Outcome Measure(s): Body mass, rectal temperature, 4-site mean weighted skin temperature, plasma stress hormone concentrations, and environmental symptoms questionnaire (ESQ) score. Results: Participants were hypohydrated (body mass -4.23% ± 0.22%) post-EXDE. Rectal temperature for the NF group was significantly greater than for the IV group {P= .023) at 30 minutes after beginning REHY (REHY30) and greater than OR, IV, and IV + OR (P ≤ .009) but not AL (P = .068) at REHY60. Mean weighted skin temperature during AL was less than during IV + OR at REHY5 (P= .019). The AL participants demonstrated increased plasma cortisol concentrations compared with IV + OR, independent of time (P = .015). No differences existed between catecholamine concentrations across treatments (P > .05). The ESQ score was increased at REHY60 for NF, AL, OR, and IV (P< .05) but not for IV + OR (P = .217). The NF ESQ score was greater than that of IV + OR at REHY60 (P=.012). Conclusions: Combination IV + OR REHY reduced body temperature to a greater degree than OR and AL REHY when compared with NF. Future studies addressing clinical implications are needed. [ABSTRACT FROM AUTHOR]

The article discusses a study to compare Pediatric Quality of Life Generic Core Scale (PedsQL) scores between adolescent athletes (ATH) and general, healthy adolescents (GEN). The study concluded that the ATH group scored higher than the GEN group for total and psychosocial summary scores, emotional and social functioning subscale scores, and physical functioning. Adolescent ATH also reported better health-related quality of life (HRQOL) than GEN, particularly in emotional functioning.

The article reports a study which examined injury risk factors of strength and jump biomechanics in elite and recreational female youth soccer players. The results revealed that elite players were similar to recreational players in all measures of hip and knee strength, vertical jump height, and normalized knee separation. This suggests that recommendations generated from research with elite youth soccer players could be generalized to recreational players.

The article presents the findings of a case-control study which examines the effect of 2 weeks of abdominal draw-in maneuver (ADIM) and cocontraction training on abdominal muscle thickness and activation timing and to monitor pain and function in patients with low back pain (LBP). The study showed an interaction between the LBP and control groups. It revealed that cocontraction of the ankle dorsiflexors with ADIM training might result in associated pain management in LBF patients.