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1.
J Sch Psychol ; 92: 49-65, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35618382

RESUMO

This study aimed to understand school mental health providers' experiences with racism and other forms of discrimination (i.e., gendered-based discrimination) at work, with an exclusive focus on early career Black women. Participants included 10 Black women in school-based mental health fields, namely school psychology and school counseling. All participants completed one individual interview and data analysis was grounded in a transcendental phenomenological approach. Findings revealed three key themes: (1) Affinity and Action, (2) Individual Experience of Discrimination, and (3) Systemic Racism and Discrimination Impacting Students of Color. Participants were passionate about advocating for all students and liberating marginalized students from oppressive school structures. However, participants' own experiences with discrimination impacted their well-being and job satisfaction. The participating women utilized several strategies to cope and push for change (e.g., reporting to the human resource personnel). Yet, people in power precluded their efforts and the emotional toll led some participants to question whether they should transition to a new field of practice. Findings from this research support calls for increased attention to Black women in school mental health fields, because they are placed at risk of experiencing work discrimination due to their intersectional identities.


Assuntos
Racismo , Local de Trabalho , Feminino , Humanos , Satisfação no Emprego , Saúde Mental , Instituições Acadêmicas
2.
Sports Biomech ; : 1-14, 2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-34962188

RESUMO

The primary aim of this investigation was to describe the energy flow through the kinetic chain during softball hitting using a segmental power analysis. Twenty-three NCAA Division I collegiate softball athletes (20.4 ± 1.7 yr; 166.7 ± 22.0 cm; 74.9 ± 15.9 kg) performed three maximum effort swings off a stationary tee placed in the middle of the strike zone. Pelvis, trunk, humerus, forearm and hand segment powers were integrated across four phases of the softball swing (load, stride, acceleration, and follow-through). The load and stride phases had low segment energy inflow and outflow values as well as net segment energy flow for all body segments compared to subsequent phases of the swing. The acceleration phase showed large trunk inflow values relative to the pelvis. There was also descriptively larger front compared to back-side upper extremity inflow. Finally, the follow-through phase showed primarily energy outflow for the upper extremity segments likely attributed to slowing down rotation.

3.
JB JS Open Access ; 5(1): e0060, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32309763

RESUMO

BACKGROUND: Athletes who have sustained a tear of the anterior cruciate ligament (ACL) are at a greater risk of re-tear and of developing other adverse outcomes, such as knee osteoarthritis, compared with uninjured athletes. Relaxin, a peptide hormone similar in structure to insulin, has been shown to interfere with the structural integrity of the ACL in female individuals. The purpose of the present study was to evaluate dynamic knee valgus and the serum relaxin concentration (SRC) in athletes who had previously sustained a torn ACL and in those who had not. METHODS: The study included 22 female athletes, divided into 2 groups: those who had previously sustained a torn ACL (4 participants; torn ACL in the dominant leg in all cases) and those who had not (18 participants). Kinematic data were collected at 100 Hz. To assess dynamic knee valgus, participants performed a single-leg squat, a single-leg crossover dropdown, and a drop vertical jump at 2 time points in the menstrual cycle of the patient, pre-ovulatory and mid-luteal. SRC was determined with use of the Human Relaxin-2 Immunoassay using a blood sample obtained during the mid-luteal phase of the menstrual cycle. RESULTS: Independent samples t tests were utilized to compare the differences in dynamic knee valgus and SRC between groups. For the single-leg squat, participants with a prior torn ACL were found to have significantly higher dynamic knee valgus at the mid-luteal phase but not at the pre-ovulatory phase. For the drop vertical jump and single-leg crossover dropdown, participants with a prior torn ACL were found to have significantly higher dynamic knee valgus at both the pre-ovulatory and mid-luteal phases. SRC was also significantly higher among participants with a prior torn ACL. CONCLUSIONS: Participants who had previously sustained a torn ACL had higher SRC and more dynamic knee valgus compared with those who had not. Further investigation of the effects of hormones as a risk factor for reinjury in participants with a prior ACL tear may be worthwhile. In addition, it may be worth monitoring hormonal and biomechanical properties in athletes during the long-term recovery from ACL reconstruction. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

4.
J Sports Sci ; 38(1): 46-52, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31658889

RESUMO

The purpose of this study was to determine the influence of pelvis and torso angular jerk on a performance indicator of hitting, specifically hand velocity. Eighteen softball athletes were analysed (20.3 ± 1.6 years; 164.9 ± 24.9 cm; 74.4 ± 14.0 kg). Participants were instructed to execute 3 maximum effort swings off a stationary tee at the middle "strike-zone" location. Angular jerk data were analysed during the acceleration phase of the swing, the time between foot contact and ball contact. Quadratic regression analyses were conducted to examine the relationship of minimal pelvis angular jerk and minimal torso angular jerk to angular hand velocity at ball contact. No significant relationship was found between pelvis angular jerk and angular hand velocity at ball contact (r = 0.192, p = 0.754). The curvilinear regression model for pelvis angular jerk produced: R2 = 0.037; F (2, 17) = 0.288; p = 0.754. Lack of significant findings suggests a relationship between jerk and angular hand velocity does not exist within female softball hitting. Future research should investigate the timing of minimal jerk through the acceleration phase as a predictor of angular hand velocity, rather than the value of jerk itself.


Assuntos
Desempenho Atlético/fisiologia , Beisebol/fisiologia , Mãos/fisiologia , Pelve/fisiologia , Tronco/fisiologia , Aceleração , Fenômenos Biomecânicos , Feminino , Humanos , Destreza Motora/fisiologia , Movimento/fisiologia , Estudos de Tempo e Movimento , Adulto Jovem
5.
J Sport Rehabil ; 28(4): 304-310, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29252089

RESUMO

Context: Hip abductor musculature contributes to the stability of the pelvis, which is needed for efficient energy transfer from the lower-extremity to the upper-extremity during overhead throwing. Objective: The purpose of this study was to examine the effects of a bilateral hip abduction fatigue protocol on overhead-throwing kinematics and passive hip range of motion. Design: Prospective cohort study. Setting: Controlled laboratory setting. Participants: A convenience sample of 19 collegiate female softball players (20.6 [1.9] y; 169.3 [9.7] cm; 73.2 [11.2] kg). Main Outcome Measures: Repeated hip abduction to fatigue was performed on an isokinetic dynamometer for 3 consecutive days. Trunk and shoulder kinematics during throwing and hip internal and external rotation range of motion were analyzed prior to fatigue on day 1 (prefatigue) and following fatigue on day 3 (postfatigue). Results: Repeated-measures analysis of variances revealed no statistically significant differences in trunk and shoulder kinematics prefatigue and postfatigue. A statistically significant time × side × direction interaction (F2,36 = 5.462, P = .02, ηp2=.233 ) was observed in hip passive range of motion. A decrease in throwing-side hip internal rotation prefatigue to postfatigue (mean difference = -2.284; 95% confidence interval, -4.302 to -0.266; P = .03) was observed. Conclusions: The hip abductor fatigue protocol used in this study did not significantly alter trunk and upper-extremity throwing kinematics. The lack of changes may indicate that fatigue of the hip abductors does not contribute to trunk and shoulder kinematics during throwing or the protocol may not have been sport-specific enough to alter kinematics.


Assuntos
Quadril/fisiologia , Fadiga Muscular , Músculo Esquelético/fisiologia , Amplitude de Movimento Articular , Ombro/fisiologia , Fenômenos Biomecânicos , Feminino , Humanos , Estudos Prospectivos , Rotação , Adulto Jovem
6.
J Sport Rehabil ; 28(2): 196-204, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29140180

RESUMO

CONTEXT: Studies have found that a 20% reduction in energy generation from the lumbopelvic-hip complex during overhead throws leads to a 34% increase in load on the shoulder. OBJECTIVE: The purpose of this study was to assess the effects of lumbopelvic-hip complex stability, via the single leg squat assessment, on throwing mechanics of softball athletes. DESIGN: Prospective cohort study. SETTING: Laboratory setting. PARTICIPANTS: A total of 50 softball athletes (164.0 [104.0] cm, 65.6 [11.3] kg, 16.3 [3.8] y, 8.61 [3.62] y of experience) performed 3 overhead throws and a single leg squat on each leg. INTERVENTION: Four stability groups were derived: (1) stable on both legs (bilateral stability), (2) unstable on the throwing side leg (TS instability) and stable on the nonthrowing side leg, (3) unstable on the nonthrowing side leg (NTS instability) and stable on the throwing side leg, and (4) unstable on both legs (bilateral instability). All throws were analyzed across 4 throwing events: foot contact (FC), maximum external shoulder rotation (MER), ball release (BR), and maximum internal shoulder rotation (MIR). MAIN OUTCOME MEASURES: Mann-Whitney U tests revealed significant differences between the bilateral stability and the TS instability groups in trunk flexion at BR; the bilateral stability and the NTS instability groups in trunk flexion at BR, shoulder horizontal abduction at FC, shoulder rotation at FC, and pelvis flexion at MIR; the TS instability and the bilateral instability groups in trunk rotation at FC; and the NTS instability and the bilateral instability groups in trunk flexion at MER and shoulder rotation at FC. CONCLUSION: These findings demonstrate the different mechanisms in which energy can be lost through lumbopelvic-hip complex instability as evident in throwing mechanics. The findings from this study suggest that the current methods used for classification could act as a tool for coaches, physicians, and athletic trainers when assessing their athletes' injury susceptibility.


Assuntos
Beisebol/fisiologia , Pelve , Amplitude de Movimento Articular , Ombro , Tronco , Adolescente , Atletas , Fenômenos Biomecânicos , Feminino , Humanos , Estudos Prospectivos , Rotação , Adulto Jovem
7.
J Strength Cond Res ; 33(2): 466-473, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28225525

RESUMO

Oliver, GD, Plummer, HA, Washington, JK, Weimar, WH, and Brambeck, A. Effects of game performance on softball pitchers and catchers. J Strength Cond Res 33(2): 466-473, 2019-The purpose of this study was to examine the effects of game exposure on pitchers and catchers' hip and glenohumeral range of motion (ROM), isometric strength, and vertical jump performance and power. Five college female softball pitchers (174.24 ± 7.53 cm; 82.10 ± 11.27 kg; 20 ± 1.82 years) and 4 catchers (165.10 ± 9.04 kg; 68.61 ± 3.87 cm; 20 ± 1.41 years) participated. Hip and glenohumeral rotational ROM; hip and glenohumeral rotational isometric strength; hip abduction and adduction strength; and vertical jump height were assessed pre- and postgame exposure. The catchers displayed significantly greater throwing side hip internal rotation (IR) ROM (mean difference = +6.88°, p = 0.03) postgame exposure, whereas the pitchers exhibited less IR (mean difference = -2.02%, p = 0.013) and external rotation (ER; mean difference = -1.95%, p = 0.026) strength in the nonthrowing side hip pre vs. postgame exposure. The performance demands of pitchers and catchers vary greatly, causing position-specific decreases/increases in various tests following game performance. Pitchers exhibited significant decreases in nonthrowing side hip IR and ER strength. In catchers, throwing side hip IR ROM significantly increased following game exposure. Further evaluation of ROM, strength, and power is necessary as it is unknown how these changes following a game affect sports performance or risk of injury.


Assuntos
Desempenho Atlético/fisiologia , Beisebol/fisiologia , Articulação do Quadril/fisiologia , Articulação do Ombro/fisiologia , Feminino , Humanos , Amplitude de Movimento Articular/fisiologia , Rotação , Universidades , Adulto Jovem
8.
J Strength Cond Res ; 33(11): 3049-3055, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29781937

RESUMO

Peart, A, Wadsworth, D, Washington, J, and Oliver, G. Body composition assessment in female National Collegiate Athletic Association Division I softball athletes as a function of playing position across a multiyear time frame. J Strength Cond Res 33(11): 3049-3055, 2019-The purpose of this study was to record changes in total body mass, lean body mass (LBM), fat mass (FM), and body fat percentage (BF%) in female National Collegiate Athletic Association (NCAA) Division I level softball athletes over a multiyear time frame using dual-energy x-ray absorptiometry (iDXA). Forty-two (20.36 ± 1.59 years) NCAA Division I collegiate softball athletes volunteered over 2 years. Subjects tested 3 times throughout the season (pre-season, mid-season, and post-season) in 2015-2017. Total and regional LBM, FM, and BF% were measured by the iDXA. A mixed-design analysis of variance was performed to examine LBM, FM, BF%, and player position interaction over time. Where appropriate, post hoc tests were used to determine statistically different variables (p ≤ 0.05). Lean body mass decreased significantly (p = 0.048) from mid-season (50.02 ± 0.28) to post season (49.67 ± 0.37). Fat mass and BF% decreased significantly for all playing positions over the season except for pitchers, who showed significantly (p < 0.000) higher levels of FM (26.56 ± 1.74) and BF% (31.77 ± 1.14) than all other positions. The current study revealed that all athletes decreased in LBM during the competitive season. Pitchers from this study consistently maintain a higher FM and BF% than the catchers, infielders, and outfielders. These data reveal that more emphasis of training and conditioning for optimal performance should be focused on the pitching position to maintain a healthy body composition.


Assuntos
Beisebol , Composição Corporal , Absorciometria de Fóton , Tecido Adiposo , Atletas , Feminino , Humanos , Estudos Longitudinais , Músculo Esquelético , Fatores de Tempo , Universidades , Adulto Jovem
9.
Int J Sports Phys Ther ; 13(4): 700-706, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30140563

RESUMO

BACKGROUND: The scapula is a critical link utilized in the kinetic chain to achieve efficient overhead movement and transfer energy from the lower extremity to the upper extremity. Additionally, daily activities such as sitting at a computer or driving in a car may negatively influence an individual's ability to maintain proper body posture and therefore compromise those movements. To reduce these negative influences, posture garments have been designed to cue the individual in maintaining and improving posture and alignment, specifically targeting scapular positioning. PURPOSE: The purpose of this study was to compare scapular positioning between an IntelliSkin™ posture-cueing compression garment and a generic performance garment on scapular kinematics during static standing.Study Design: Case control. METHODS: Forty active females (1.68 ± 0.07 m; 67.29 ± 11.25 kg) stood in a natural standing position while wearing two different garments: IntelliSkin™ posture-cueing compression garment and a generic performance garment. Kinematic data were collected at 100 Hz using an electromagnetic tracking system (trakSTAR™, Ascension Technologies, Inc., Burlington, VT, USA) synced with The MotionMonitor® (Innovative Sports Training, Chicago, IL., USA). RESULTS: Repeated measures ANOVAs revealed a statistically significant Shirt by Side interaction for scapular protraction/retraction (F(1,39) = 52.91, p ≤ 0.05) and main-effect of Shirt for scapula anterior/posterior tilt (F(1,39) = 96.45, p ≤ 0.05). Individuals showed increased retraction and posterior tilt while wearing the IntelliSkin™ posture-cueing compression garment. CONCLUSION: The results of the current study indicate that the IntelliSkin™ posture-cueing compression garment improved scapular positioning during static standing posture. The IntelliSkin™ posture-cueing compression garment may provide clinicians an adjunct strategy to include with rehabilitative protocols. LEVEL OF EVIDENCE: Diagnosis, Level 3.

10.
Int J Sports Phys Ther ; 13(3): 493-500, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30038835

RESUMO

BACKGROUND: Fastpitch softball is a popular sport for young females. However, data are limited describing youth pitching mechanics. Normative data describing pitching mechanics in the two youngest player pitch leagues are critical to gaining an improved understanding of proper mechanics in an attempt to establish injury prevention programs. PURPOSE: The purpose of this study was to examine pitching mechanics in Little League softball pitchers and examine the relationship of these mechanics and participant anthropometrics to ball velocity. STUDY DESIGN: Cross-sectional. METHODS: Twenty-three youth softball pitchers (11.4 ± 1.5 years; 154.6 ± 10.5 cm; 51.0 ± 8.0 kg) participated. An electromagnetic tracking system was used to collect kinematic data for three fastball trials for strikes over a regulation distance to a catcher. The pitching motion was divided into three events: top of back swing, stride foot contact, and ball release. RESULTS: Youth who were older (r = 0.745, p < 0.001) and taller (r = 0.591, p = 0.003) achieved greater ball velocity. Trunk kinematics revealed that greater trunk flexion throughout the three throwing events of top of back swing (r = 0.429, p = 0.041), stride foot contact (r = 0.421, p = 0.046), and ball release (r = 0.475, p = 0.022) yielded greater ball velocity. Additionally, greater trunk rotation to the throwing arm side (r = 0.450, p = 0.031) at top of back swing and greater trunk lateral flexion to the glove side at ball release (r = 0.471, p = 0.023) resulted in greater ball velocity. CONCLUSION: The significant relationships found between pitching mechanics and ball velocity only occurred at the trunk, which may highlight the importance of utilizing the trunk to propel the upper extremity in dynamic movements. LEVEL OF EVIDENCE: Diagnosis, Level 4.

11.
Int J Sports Med ; 39(7): 571-575, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29758570

RESUMO

During an overhead throw, the gluteal muscle group stabilizes the lumbopelvic-hip complex (LPHC), leading to efficient energy transfer from the lower to upper extremity. It has been shown that LPHC instability can lead to throwing pathomechanics. The single leg squat has become a common assessment for LPHC stability, and could be used to determine the effects of fatigue on throwing athletes. The purpose of this study was to determine the effects of an acute abduction fatigue protocol on the LPHC of collegiate softball players via the single leg squat assessment of the leg ipsilateral to the throwing arm. Eighteen National Collegiate Athletic Association Division I softball players volunteered (20.5±1.9 years; 169.4±10.0 cm; 72.9±11.5 kg). Each participant performed a single leg squat on the leg ipsilateral to the throwing arm prior to and post side-lying hip abduction fatigue. LPHC and lower extremity kinematics were examined to determine potential effects of fatigue on LPHC stability. There were no significant main effects or interactions of LPHC or lower extremity kinematics during the single leg squat assessments across the fatigue protocol. Based on the current study, an acute bout of fatigue to the hip abductors does not affect LPHC stability in single leg squat execution.


Assuntos
Beisebol/fisiologia , Quadril/fisiologia , Vértebras Lombares/fisiologia , Fadiga Muscular/fisiologia , Ossos Pélvicos/fisiologia , Fenômenos Biomecânicos , Humanos , Movimento/fisiologia , Postura/fisiologia , Tronco/fisiologia , Adulto Jovem
12.
J Strength Cond Res ; 32(6): 1545-1553, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29786622

RESUMO

Oliver, GD, Washington, JK, Barfield, JW, Gascon, SS, and Gilmer, G. Quantitative analysis of proximal and distal kinetic chain musculature during dynamic exercises. J Strength Cond Res 32(6): 1545-1553, 2018-Proximal to distal sequencing for the dynamic movement of throwing is dependent on the movement and stability of the lumbopelvic-hip complex (LPHC) and scapula. Although the need for proximal stability for distal mobility has been vastly documented, pre-throwing programs tend to focus on the traditional rotator cuff activation exercises before long toss. Thus, it was the purpose of this study to describe muscle activations of LPHC stabilizing musculature (bilateral gluteus medius and maximus) and scapular stabilizing musculature (dominant side latissimus dorsi, lower trapezius, upper trapezius, and serratus anterior) during 5 kinetic chain exercises that could be implemented in a throwing program. It was hypothesized that both the LPHC and the scapular stabilizing musculature would exhibit moderate to high activation during all the selected kinetic chain exercises. Nineteen healthy college students (23.2 ± 7.2 years; 176.7 ± 17.9 cm; 78.0 ± 28.6 kg) participated. Surface electromyography was used to measure muscle activity in the LPHC and scapular stabilizing musculature during 5 kinetic chain exercises. A nonparametric Friedman test revealed significantly different muscle activations as a factor of exercise for each muscle, χ(18) = 417.220, p < 0.001. The 5 kinetic chain exercises successfully elicited moderate to high muscle activation in all musculature, except the upper trapezius. Because greater muscle activation of the LPHC and scapular stabilizers are crucial during a throwing task, these exercises are recommended for pre-throwing program implementation because they efficiently prepare the stabilizing musculature for lengthy or strenuous throwing tasks, resulting in a potential decrease in injury susceptibility.


Assuntos
Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , Ombro/fisiologia , Adulto , Fenômenos Biomecânicos , Eletromiografia , Feminino , Quadril/fisiologia , Humanos , Masculino , Movimento , Manguito Rotador , Escápula/fisiologia , Músculos Superficiais do Dorso/fisiologia , Adulto Jovem
13.
Int J Sports Med ; 39(6): 462-467, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29665612

RESUMO

The purpose of this study was to determine how stride length, segmental sequencing of the pelvis, trunk, humerus, and forearm velocities and accelerations, and the timing of these values change as youth mature. Thirteen youth baseball pitchers participated at three consecutive time points: visit 1 (10.7±1.3 years; 151.8±10.7 cm; 45.0±9.65 kg), visit 2 (11.5±1.6 years; 155.5±11.1 cm; 50.4±10.0 kg), and visit 3 (12.4±1.7 years; 161.5±11.7 cm; 56.4±10.8 kg). Participants executed three pitches for a strike to a catcher. The maximum value of stride length and segmental speeds and accelerations was recorded. The point at which these maximum values occurred during the throw was calculated as a percentage from hand separation to maximum internal rotation of the shoulder. Repeated measures ANOVAs and Friedman Tests revealed no statistically significant differences between stride length, segmental speeds and accelerations, and their percentage of the pitch between the three visits. However, there was a significant increase in ball velocity across visits. No significant changes occurred in pitching mechanics between the ages of 10-12. The authors speculate the lack of differences can be accounted for because these ages are prior to any significant pubescent changes. Future research should consider pre- and post- pubescent age groups.


Assuntos
Beisebol/fisiologia , Destreza Motora/fisiologia , Maturidade Sexual/fisiologia , Aceleração , Fenômenos Biomecânicos , Criança , Antebraço/fisiologia , Humanos , Úmero/fisiologia , Estudos Longitudinais , Pelve/fisiologia , Rotação , Tronco/fisiologia
14.
Psychophysiology ; 52(6): 745-53, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25532594

RESUMO

Two studies examined the interaction of an acoustic startle stimulus and visual go/no-go task stimuli on startle reactivity and task performance. In the first study, an acoustic stimulus (50 ms, 100 dB noise) was presented alone or with a green (go) or red (no-go) circle; in the second study, a prepulse (50 ms, 75 dB noise) was presented alone or 120 ms before the startle stimulus or circle. The startle stimulus speeded responses to the go stimuli and increased the covert false alarm rate in the no-go condition (measured by EMG activity in the hand), although very few overt errors were made in the no-go condition. Startle response magnitude was increased by a circle but decreased by a prepulse. The speeding of go responses caused by a startle stimulus was attenuated by the occurrence of a startle response, suggesting that an intense accessory stimulus can facilitate responding to an imperative stimulus, and that the startle response to that intense stimulus can interfere with that facilitation.


Assuntos
Inibição Psicológica , Tempo de Reação/fisiologia , Reflexo de Sobressalto/fisiologia , Estimulação Acústica , Adolescente , Piscadela/fisiologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Adulto Jovem
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