Sequential order of swing phase initiation in baseball

In order to successfully hit a baseball, hitters must utilize a series of preparatory movements (swing phases) which include shifting their body weight, stepping, landing, and swinging. The purpose of this study was to examine the differences between start times for swing phases (shifting, stepping, landing, and swinging)for currently active baseball players. Participants (n = 12) were all current collegiate baseball athletes. Retroreflective markers, surface electromyography (EMG) and two force platforms were utilized to complete a swing analysis. Each participant completed five swinging trials off a tee. All dependent variables were compared using a repeated measures 1×4 ANOVA with LSD post hoc comparison (p < 0.05) if necessary. The results demonstrated that the participants started the swing phases in a statistically significant sequence of shifting, stepping, landing, and swinging. The ability of the athletes to start the swing phases in this sequential order may be advantageous to regulate spatial parameters of their swing and provide more time to generate power. These results allow for coaches to better understand how to instruct their athletes to be successful at the plate.

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Examining Changes in Bat Swing Kinematics in Different Areas of the Strike Zone in Collegiate Baseball Players

International Journal of Kinesiology and Sports Science ◽

10.7575//aiac.ijkss.v.8n.2p.1 ◽

2020 ◽

Vol 8 (2) ◽

pp. 1

Author(s):

Charles C. Williams ◽

Paul T. Donahue ◽

Samuel J. Wilson ◽

J. Grant Mouser ◽

Christopher M. Hill ◽

...

Keyword(s):

Repeated Measures ◽

National Collegiate Athletic Association ◽

Baseball Players ◽

Warm Up ◽

Game Situation ◽

Resultant Velocity ◽

Ball Contact ◽

Collegiate Baseball ◽

Collegiate Level ◽

Bat Performance

Background: According to the National Collegiate Athletic Association (NCAA) there are over 34,000 athletes who compete in baseball at the collegiate level. These individuals spend countless hours training to improve their ability at bat performance by use of a batting tee and their position preference. However, during a game situation an athlete may swing a bat through their strike zone depending on the pitch thrown by an opposing pitcher. Objective: The aim of this investigation was to examine changes in swing kinematics throughout an individual’s strike zone in collegiate baseball players. Variables of interest included resultant velocity at ball contact (RVBC) and the angle of the bat at ball contact (BABC). Methodology: A series of markers were placed on the tee and bat to record swing kinematic variables of interest. Participants completed a brief two-minute on-deck warm-up protocol before being counterbalanced into completing 15 swing trials in various regions of their respective strike zone. A ten-minute washout period was completed followed by another 15 swing trials throughout their strike zone until there was a total of 45 swing trials, having 5 swing trials completed in each of the nine regions of the strike zone. Results: Repeated measures analysis of variance were used to examine swing kinematic variables of interest. Significant differences were found in RVBC along with significant differences in BABC (p<.05). Conclusions: Knowledge of this information can allow both athlete and sport coach to identify areas of weakness when addressing their hitting performance in preparation for an at bat situation during a game.

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Change in Glenohumeral Rotation and Scapular Position After a Division I Collegiate Baseball Season

Journal of Sport Rehabilitation ◽

10.1123/jsr.22.2.115 ◽

2013 ◽

Vol 22 (2) ◽

pp. 115-121 ◽

Cited By ~ 9

Author(s):

Stephen John Thomas ◽

Charles B. Swanik ◽

Kathleen Swanik ◽

John D. Kelly

Keyword(s):

Outcome Measures ◽

External Rotation ◽

Division I ◽

Laboratory Setting ◽

Anterior Instability ◽

Baseball Players ◽

Elbow Injury ◽

Type Design ◽

Dependent Variables ◽

Collegiate Baseball

Context:Pathologies such as anterior instability and impingement are common in baseball and have been linked to decreases in internal-rotation (IR) motion and concurrent increases in external-rotation (ER) motion. In addition, alterations to scapular upward rotation have been identified in this population.Objective:To measure glenohumeral (GH) IR and ER rotation, total range of motion (ROM), and scapular upward rotation throughout the course of a Division I collegiate baseball season.Design:Pretest to posttest study.Setting:Controlled laboratory setting.Participants:Thirty-one collegiate baseball players with no current shoulder or elbow injury completed this study.Intervention:Participants were measured for all dependent variables at preseason and postseason.Main Outcome Measures:GH IR and ER were measured supine with the scapula stabilized. Total GH ROM was calculated as the sum of IR and ER measures. Scapular upward rotation was tested at rest, 60°, 90°, and 120° of GH abduction in the scapular plane.Results:Overall, the dominant arm had significantly less GH IR and significantly more ER than the nondominant arm. The total motion on the dominant arm was significantly less than on the nondominant arm. No significant differences were observed from preseason to postseason for IR, ER, or total motion. Dominant-arm scapular upward rotation significantly decreased at 60°, 90°, and 120° of abduction from preseason to postseason.Conclusion:Collegiate baseball players presented with significant GH-motion differences (decreases in IR and increases in ER) in their dominant arm compared with their nondominant arm. There was also significantly less total motion on the dominant arm. After 12 wk of competitive Division I collegiate baseball, there were significant decreases in upward rotation over the season.

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The Effect of Grip Width on Bench Press Performance

International Journal of Sport Biomechanics ◽

10.1123/ijsb.8.1.1 ◽

1992 ◽

Vol 8 (1) ◽

pp. 1-10 ◽

Cited By ~ 30

Author(s):

Loree L. Wagner ◽

Sharon A. Evans ◽

Joseph P. Weir ◽

Terry J. Housh ◽

Glen O. Johnson

Keyword(s):

Body Weight ◽

Repeated Measures ◽

Bench Press ◽

Two Dimensional ◽

Repeated Measures Anova ◽

First Order ◽

Experienced Male ◽

Partial Correlations ◽

Press Performance ◽

Post Hoc

The purpose of this study was to determine the effects of grip width, chest depth, limb lengths, and bar path on the performance of a maximal bench press. Subjects were 24 experienced male weight trainers. Bench press performance was assessed at six different grip widths (G1–G6). Repeated-measures ANOVA with Tukey post hoc comparisons revealed that bench press strength values at the two moderate grip widths (G3 and G4) were significantly greater than either the narrow or wide grip widths. First-order partial correlations showed no significant relationship between strength values and anthropometric variables when adjusted for differences in body weight. Standard two-dimensional cinematographic procedures were used to film a subsample (n = 6) while bench pressing using G1, G3, and G6. The results of the statistical comparisons of bar path indicated that as grip width increased, the horizontal and vertical distance from the bar to the shoulder decreased.

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Patterns of Body Weight Changes in Patients With Hypothyroidism, a Retrospective Study From Basrah, Southern Iraq

Journal of the Endocrine Society ◽

10.1210/jendso/bvab048.1697 ◽

2021 ◽

Vol 5 (Supplement_1) ◽

pp. A832-A833

Author(s):

Haider A Alidrisi ◽

Samih Abed Odhaib ◽

Mahmood Thamer Altemimi ◽

Nassar Taha Alibrahim ◽

Ali Hussain Alhamza ◽

...

Keyword(s):

Body Weight ◽

Repeated Measures ◽

Thyroid Stimulating Hormone ◽

Newly Diagnosed ◽

Weight Changes ◽

Adequate Treatment ◽

Study Results ◽

Hormonal Therapies ◽

One Year ◽

Post Hoc

Abstract Background: Weight gain is one of the most important hypothyroidism-related concerns among patients with hypothyroidism. However, not as expected, thyroxine replacement does not necessarily result in body weight (BWT) reduction among those patients. The study aimed to assess the patterns of BWT changes through time in patients with hypothyroidism. Method: A retrospective database study from Faiha Specialized Diabetes, Endocrine, and Metabolism Center. A total of 346 adult patients with hypothyroidism, 192 newly diagnosed and 154 known, who had 1 visit every 3 months, 5 visits per one year. From those patients, 116 new and 69 known had completd 9 visits per two years. Each visit involved thyroid-stimulating hormone (TSH) and BWT measurements. Patients with chronic liver or renal disease, diabetes mellitus, thyroid cancer, or other malignancies, pregnancy, and on steroid or hormonal therapies were excluded. The patients were further subdivided based on average TSH levels into controlled (TSH≤4.2 μIU/mL) and uncontrolled TSH>4.2 μIU/mL. Repeated measures ANOVA with a Greenhouse-Geisser correction and Post hoc tests using the Bonferroni correction were used to evaluate BWT changes through the study. Results: Both newly diagnosed and known hypothyroidism, over one and two years, in patients with average TSH>4.2 μIU/mL, BWT increased significantly through visits. For newly diagnosed over one year, (F(2.41, 321.60) = 3.28, p = 0.03), and mean BWT increase = 1.4 ± 0.38 kg from 3rd to 12th month visits, (p = 0.004). For newly diagnosed over two years, (F(3.10, 263.89) = 9.08, P < 0.0005), mean BWT increase = 3.02 ± 0.77 kg from 3rd to 24th month visits, (p = 0.007). And for known hypothyroidism over one year, (F(2.56, 187.47) = 7.11, p = 0.0003), mean BWT increase = 1.97 ± 0.64 kg at 12th month visit, and over two years, (F(2.35, 77.56) = 4.67, P = 0.009), mean BWT increase = 3.78 ± 1.26 kg at 24th month visit. While in all other patients with average TSH≤4.2 μIU/mL, the BWT changed non-significantly through visits. For newly diagnosed patients over one year and two years (p = 0.10, 0.34 respectively), and known patients over one year and two years (p = 0.47, 0.34 respectively). Conclusion: In contrary to what is believed, adequate treatment with thyroxine does not associate with weight reduction. Instead, either the patient kept on the same weight or continued to gain more weight.

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Annual rhythms in adults’ lifestyle and health (ARIA): protocol for a 12-month longitudinal study examining temporal patterns in weight, activity, diet, and wellbeing in Australian adults

BMC Public Health ◽

10.1186/s12889-020-10054-3 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Rachel G. Curtis ◽

Timothy Olds ◽

François Fraysse ◽

Dorothea Dumuid ◽

Gilly A. Hendrie ◽

...

Keyword(s):

Physical Activity ◽

Body Weight ◽

Weight Gain ◽

Repeated Measures ◽

Vigorous Physical Activity ◽

Activity Patterns ◽

Intervention Strategy ◽

Temporal Patterns ◽

Trial Registration ◽

Multi Level

Abstract Background Almost one in three Australian adults are now obese, and the rate continues to rise. The causes of obesity are multifaceted and include environmental, cultural and lifestyle factors. Emerging evidence suggests there may be temporal patterns in weight gain related, for example, to season and major festivals such as Christmas, potentially due to changes in diet, daily activity patterns or both. The aim of this study is to track the annual rhythm in body weight, 24 h activity patterns, dietary patterns, and wellbeing in a cohort of Australian adults. In addition, through data linkage with a concurrent children’s cohort study, we aim to examine whether changes in children’s body mass index, activity and diet are related to those of their parents. Methods A community-based sample of 375 parents aged 18 to 65 years old, residing in or near Adelaide, Australia, and who have access to a Bluetooth-enabled mobile device or a computer and home internet, will be recruited. Across a full year, daily activities (minutes of moderate to vigorous physical activity, light physical activity, sedentary behaviour and sleep) will be measured using wrist-worn accelerometry (Fitbit Charge 3). Body weight will be measured daily using Fitbit wifi scales. Self-reported dietary intake (Dietary Questionnaire for Epidemiological Studies V3.2), and psychological wellbeing (WHOQOL-BREF and DASS-21) will be assessed eight times throughout the 12-month period. Annual patterns in weight will be examined using Lowess curves. Associations between changes in weight and changes in activity and diet compositions will be examined using repeated measures multi-level models. The associations between parent’s and children’s weight, activity and diet will be investigated using multi-level models. Discussion Temporal factors, such as day type (weekday or weekend day), cultural celebrations and season, may play a key role in weight gain. The aim is to identify critical opportunities for intervention to assist the prevention of weight gain. Family-based interventions may be an important intervention strategy. Trial registration Australia New Zealand Clinical Trials Registry, identifier ACTRN12619001430123. Prospectively registered on 16 October 2019.

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Changes in Maximal Strength and Home Run Performance in NCAA Division I Baseball Players Across 3 Competitive Seasons: A Descriptive Study

Journal of Functional Morphology and Kinesiology ◽

10.3390/jfmk6010004 ◽

2021 ◽

Vol 6 (1) ◽

pp. 4

Author(s):

W. Guy Hornsby ◽

Abigail L. Tice ◽

Jason D. Stone ◽

Justin J. Merrigan ◽

Joshua Hagen ◽

...

Keyword(s):

Ncaa Division I ◽

Repeated Measures ◽

National Collegiate Athletic Association ◽

Descriptive Study ◽

Peak Force ◽

Division I ◽

Maximal Strength ◽

Baseball Players ◽

Repeated Measures Analysis ◽

Division 1

The purpose of this longitudinal, descriptive study was to observe changes in maximal strength measured via isometric clean grip mid-thigh pull and home runs (total and home runs per game) across three years of training and three competitive seasons for four National Collegiate Athletic Association (NCAA) Division 1 baseball players. A one-way repeated measures analysis of variance (ANOVA) was performed, revealing significant univariate effects of time for peak force (PF) (p = 0.003) and peak force allometrically scaled (PFa) (p = 0.002). Increases in PF were noted from season 1 to season 2 (p = 0.031) and season 3 (p = 0.004), but season 2 was not significantly different than season 3 (p = 0.232). Additionally, increases in PFa were noted from season 1 to season 2 (p = 0.010) and season 3 (p < 0.001), but season 2 was not significantly different than season 3 (p = 0.052). Home runs per game rose from the 2009 (0.32) to 2010 season (1.35) and dropped during the 2011 season (1.07). A unique aspect of the study involves 2010 being the season in which ball-bat coefficient of restitution (BBCOR) bats were introduced to the NCAA competition.

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Efficacy of galcanezumab in patients with migraine who did not benefit from commonly prescribed preventive treatments

BMC Neurology ◽

10.1186/s12883-021-02196-7 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Dulanji K. Kuruppu ◽

Joshua Tobin ◽

Yan Dong ◽

Sheena K. Aurora ◽

Laura Yunes-Medina ◽

...

Keyword(s):

Repeated Measures ◽

Migraine Headache ◽

Mixed Model ◽

Preventive Treatment ◽

Response Rates ◽

Toxin A ◽

Double Blind ◽

Preventive Medication ◽

Onabotulinum Toxin A ◽

Post Hoc

Abstract Background Galcanezumab is a calcitonin gene-related peptide (CGRP) monoclonal antibody (mAb) indicated for the preventive treatment of migraine. While galcanezumab has demonstrated efficacy in patients who did not respond to prior preventive medications in general, its efficacy in patients who did not benefit from individual, commonly prescribed preventive treatments due to inadequate efficacy or safety/tolerability remains unknown. Methods CONQUER was a 3-month, randomized, double-blind, placebo-controlled, phase 3b study that enrolled patients with episodic or chronic migraine who had 2 to 4 migraine preventive medication category failures in the past 10 years. Patients were randomly assigned 1:1 to receive placebo (N = 230) or galcanezumab 120 mg/month (240 mg loading dose; N = 232). Post hoc analyses were conducted to determine the efficacy of galcanezumab in patients who had not benefited from six of the most commonly prescribed migraine preventive medications. The mean change from baseline in monthly migraine headache days and ≥ 50 % response rates were assessed over months 1–3. Improvement in Migraine-Specific Questionnaire Role Function-Restrictive (MSQ-RFR) scores were assessed at month 3. The endpoints were estimated via mixed model with repeated measures. Results The most common treatment failures due to inadequate efficacy or safety/tolerability, which at least 20 % of patients reported trying without benefit, included topiramate, amitriptyline, propranolol, valproate or divalproex, onabotulinum toxin A, and metoprolol. Patients who had not previously benefited from these treatments had a greater mean reduction in monthly migraine headache days across months 1–3 in the galcanezumab group compared to placebo (all p < 0.01). More patients treated with galcanezumab experienced a ≥ 50 % reduction from baseline in monthly migraine headache days across months 1–3 compared to placebo (all p < 0.05). Galcanezumab-treated patients had a greater improvement in mean MSQ-RFR scores at month 3 compared to placebo (all p < 0.01). Conclusions In this population, galcanezumab was effective in reducing monthly migraine headache days, improving response rates, and enhancing quality of life in patients who had not previously benefited from topiramate, amitriptyline, propranolol, valproate or divalproex, onabotulinum toxin A, and/or metoprolol due to inadequate efficacy or safety/tolerability. Trial registration ClinicalTrials.gov NCT03559257 (CONQUER).

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51 Intranasal oxytocin improves plasma non-esterified fatty acids but not distance walked or cortisol concentrations at weaning

Journal of Animal Science ◽

10.1093/jas/skaa054.053 ◽

2020 ◽

Vol 98 (Supplement_3) ◽

pp. 29-30

Author(s):

Kirsten Nickles ◽

Alejandro E Relling ◽

Anthony J Parker

Keyword(s):

Fatty Acids ◽

Body Weight ◽

Repeated Measures ◽

Production Costs ◽

Calf Growth ◽

Beef Calves ◽

Esterified Fatty Acids ◽

Randomized Design ◽

Affect Body Weight ◽

Global Positioning

Abstract Beef calves express behaviors such as walking and vocalizing to a greater extend during weaning. These behaviors increase production costs due to compromised calf growth, health, and welfare. Oxytocin treatment reduces anxious behaviors and attenuates the HPA axis, thus the objective of this experiment was to evaluate the effects of oxytocin on calf growth, cortisol, and distance walked at weaning. A total of 20 Angus x Simmental heifer calves were randomly allotted to each treatment group (n = 10), intranasal oxytocin or saline (OXT, CON). All calves were administered the respective intranasal treatment at weaning (day 0), and then placed in the same pasture. Calves were weighed and blood sampled on days 0, 1, 7, and 14. Blood samples were used to quantify non-esterified fatty acids (NEFA), β-hydroxybutyrate, and cortisol. Each heifer was fitted with a global positioning system collar that recorded calf location every 10 seconds for 16 h on days 0, 7, and 14. To further evaluate calf behavior, observations were made on days 0, 7, and 14 using instantaneous scan sampling from 0730 to 0830, 1200 to 1300, and 1700 to 1800 h. Data were analyzed using a completely randomized design with repeated measures model (SAS 9.4). Providing calves with intranasal oxytocin on the day of weaning did not have an effect on the distance walked, observed behavior, body weight, β-hydroxybutyrate, or cortisol concentrations, however, there was a day effect (P < 0.05) for these variables. Intranasal oxytocin treatment did affect NEFA concentrations, as calves in the CON group had greater NEFA concentrations on day 1 compared with calves in the OXT group (P < 0.05). These data imply that intranasal oxytocin could have the capacity to decrease mobilization of NEFA, but this change was not enough to affect body weight 14 days after weaning.

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Time of imagery’s effect on performance and self-efficacy in college baseball players

Journal of Imagery Research in Sport and Physical Activity ◽

10.1515/jirspa-2020-0019 ◽

2020 ◽

Vol 15 (1) ◽

Author(s):

Colton Haight ◽

Sandra Moritz ◽

Tanis Walch

Keyword(s):

Self Efficacy ◽

Repeated Measures ◽

Group Interaction ◽

Physical Effect ◽

Baseball Players ◽

Repeated Measures Anova ◽

Significant Time ◽

Imagery Group ◽

College Baseball ◽

Group 2

AbstractThe relationships among the time of imagery use on performance and self-efficacy in college baseball players during a hitting task was examined. Participants (n=24) were randomly assigned to one of three imagery conditions: (a) before practice, (b) during practice, (c) after practice. A one-shot MG-M imagery intervention was used. Results from a 3 (imagery group) ×2 (pretest and posttest) repeated measures ANOVA showed only a significant time by imagery group interaction for self-efficacy (F (2, 21)=4.67, p<0.05). These findings suggest that imagery had a stronger psychological effect than physical effect.

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Body Composition Modifications Due to the “Search, Rescue and Survival Training” in Male Military Firefighter Cadets

Military Medicine ◽

10.1093/milmed/usaa571 ◽

2021 ◽

Author(s):

Thiago Ramos de Barros ◽

Verônica Pinto Salerno ◽

Thalita Ponce ◽

Míriam Raquel Meira Mainenti

Keyword(s):

Body Composition ◽

Body Weight ◽

Repeated Measures ◽

Food Restriction ◽

Physical Exertion ◽

High Energy ◽

The Body ◽

Fat Free Mass ◽

Sleep Restriction ◽

Fat Percentage

ABSTRACT Introduction To train and prepare cadets for a career as firefighters in Rio de Janeiro, the second-year students of the Officers Training Course are submitted to a Search, Rescue, and Survival Training (SRST) course, which is characterized by long periods of high physical exertion and sleep restriction during a 9-day instruction module, and food restriction during a 7-day survival module. The present study investigated changes in the body composition of 39 male cadets submitted to SRST during training and 4 weeks of recovery with no restrictions in food consumption. Materials and Methods Each cadet was evaluated by anthropometric measurements at six time points: pre-SRST; after the first module; after the second module; and after 1, 2, and 4 weeks of recovery. Measurements included body girths and skinfolds, to estimate trunk (chest and waist) and limbs (arm and thigh) dimensions, as well as body composition. Repeated measures ANOVA and Friedman test were applied (depending on each data distribution). Results Statistically significant decreases in body weight (76.2; 69.8-87.2 to 63.9; 58.9-73.5 kg) and fat free mass (FFM, 69.2; 63.7-77.2 to 60.1; 56.2-68.0 kg) were observed following the second module of SRST. Following a single week of recovery, the FFM returned to pre-SRST values. Body weight returned to pre-training levels in 2 weeks. Body fat percentage and mass also significantly decreased during SRST (9.0; 7.7-12.3 to 6.5; 5.1-9.3% and 6.9; 5.6-10.0 to 6.9; 5.6-10.0 kg, respectively), which showed a slower and more gradual recovery that reached pre-SRST values after 4 weeks. The girths of arm, thigh, chest and waist significantly decreased due to SRST. The girths of the limbs (arm and thigh) returned to pre-training values after one month of recovery, while the girths of the trunk (chest and waist) did not return to pre-SRST values during the study period. Conclusions The findings suggest that men who experience periods of high energy demands and sleep restriction followed by a period of food restriction will endure unavoidable physical consequences that can be mostly reversed by a 1-month recovery.

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