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AN INVESTIGATION INTO SEASONAL POWER CHANGES IN COLLEGIATE BASEBALL PITCHERS
Get PDFThis study aimed to investigate changes in power and fatigue of collegiate baseball pitchers throughout a season to determine injury risk. Isokinetic, mobility, and performance test records were reviewed for 18 male NCAA-I baseball athletes. Testing was performed during the offseason, season start, and end of non-conference play and included medicine ball throws, hop testing, and 3-speed isokinetic testing. Statistical analysis determined that the kneeling medicine ball throw, 6-m hop, and several isokinetic outcomes decreased throughout the season. Using a combination of medicine ball throws, hop testing, and isokinetic testing at specific times during a season may provide insight into the overall fatigue level and injury risk within baseball pitchers
MUSCLE ACTIVATION PATTERNS OF UPPER EXTREMITY DURING DIFFERENT STROKES OF BADMINTON: A SINGLE SUBJECT PILOT STUDY
Get PDFThe purpose of this study was to quantify muscle activation patterns during different stroke techniques in badminton. We hypothesized that muscle activation patterns in upper extremity would be different depending on stroke techniques. We recruited a recreational badminton player. The participant performed five stroke techniques such as forehand and backhand drive, high clear, smash, and drop with electromyography sensors on wrist flexor, wrist extensor, elbow flexor, elbow extensor, middle deltoid, upper trapezius, and pectoralis major. We compared muscle activations within muscle and between stroke techniques. We found that muscle activation patterns were different depending on strokes. Our results provide background knowledge about muscle activation patterns and suggest that trainers should target different muscles depending on stroke techniques
CLUSTERING LONG-DISTANCE RUNNERS BASED ON THEIR TECHNIQUE AT ONE SINGLE SPEED DOES NOT GENERALISE TO MULTIPLE SPEEDS
Get PDFThe aim of this study was to assess whether clustering runners based on their technique resulted in consistent group allocations across multiple speeds. Eighty-four runners (34 females) completed four 4-minute running stages at 10, 11, 12 and 13 km/h. For each stage, running technique was characterised using a set of continuous variables in the sagittal plane and discrete stride-based variables. An autoencoder neural network was used for dimensionality reduction and agglomerative hierarchical clustering was applied to identify groups of runners with a similar technique. Two clusters for each speed were selected and the clustering partitions at different incremental speeds were compared. Our results showed that partitions were inconsistent across speeds, and therefore clustering results at one single speed do not generalise to the range of speeds an athlete typically runs at. Single speed clustering may be limited to drive the design of cluster-specific running training interventions and different clustering approaches are needed to better capture runners’ technique at their typical speeds
ISOKINETIC STRENGTH IN FEMALE SOCCER PLAYERS BY PLAYER POSITION
Get PDFThis study aimed to establish reference values and compare isokinetic performance in female soccer players according to player position. Eighty-seven female soccer players from the Chilean first-division soccer clubs were evaluated in isokinetic strength. The player position was grouped as goalkeeper (GK), central defender (CD), lateral defender (LD), midfielder (MF), and forward (FW). Concentric knee extension and flexion muscle strength measurements were conducted using a standardized test protocol with an angular velocity of 60º/sec. There were no differences in peak torque of knee extension and flexion between player positions in both the dominant leg (DL) and the nondominant leg (NDL). The H:Q ratio shows significant differences (p=0.0379) in the dominant leg between CD vs. MF (GK: 63.1±11.1; CD: 55.6±4.6; LD: 62.5±9.6; MF: 64.8±12.0; FW: 61.1±10.9). Our results can be used for practitioners working with female professional soccer players to assess and monitor strength according to player position to improve performance. Future studies should confirm whether these values can be used as risk factors, complementing other functional metrics (e.g., eccentric force) and different angular velocities
COMPARISON OF JOINT KINEMATICS BETWEEN DIFFERENT RESISTED SPRINT LOADS WITH DIFFERENT PHASES OF ACCELERATION OF NORMAL SPRINTS IN EXPERIENCED SPRINTERS
Get PDFThe purpose of this study was to compare joint kinematics of different active resisted loads upon different phases of the acceleration (similar velocity) of a normal sprint. Fifteen experienced male sprinters performed a 50-m sprint with maximal effort from a start block, followed by a 10, 20, 30m with resisted sprints provided by a robotic pully system that gave resp. 65, 50, 25 and 10% reduction of peak velocity, while joint kinematics were measured. The main findings were that in the contact phase most kinematics were similar between the two. During the flight phase maximal hip and knee flexion and velocity were significantly higher in the resisted sprints compared with normal sprint, especially with high resisted loads. It was concluded that most joint kinematics of different active resisted loads are comparable with the different phases of the acceleration of a normal sprint
Correlation Between Scores on the Assessment and Learning in Knowledge Spaces Placement, Preparation, and Learning Test and General Chemistry Course Outcomes for Undergraduate Students at a Public Midsize Master\u27s University
Get PDFThis study examined the problem of gateway courses in Science, Technology, Engineering, and Mathematics (STEM), specifically, high-enrollment introductory chemistry courses with high rates of D, F, withdrawal, or incomplete grades. Previous research revealed a correlation between students’ prior mathematics knowledge and introductory chemistry course outcomes. Reports using the Assessment and Learning in Knowledge Spaces Placement, Preparation, and Learning (ALEKS PPL) test were limited in number. This study conducted a non-experimental retrospective correlational analysis between undergraduate students’ ALEKS PPL test scores and introductory chemistry course grades. The study’s theoretical framework was grounded in prerequisite and placement testing theories. The major findings of the study were correlation values of rs = .244 (n = 562, p \u3c .001, two-tailed) and .233 (n = 317, p \u3c .001, two-tailed) for General Chemistry I and II, respectively. These results indicated a weak relationship between ALEKS PPL scores and introductory chemistry course grades. The findings do not support using ALEKS PPL test scores as a prerequisite for general chemistry. Future research should explore alternative mathematics instruments and their predictive value for introductory chemistry
The Water Question: Coverage, Conflict, and Confusion in Negaunee during the Typhoid Fever Epidemic of 1889
Get PDFEpidemic disease and the strain it places upon communities is the source of crucial insight into the structures and intricacies of community life. This assessment of the course of the 1889 Negaunee typhoid fever epidemic uncovers a variety of perspectives on the treatment and mitigation of the disease between August and November of 1889 in a diverse and densely-populated Iron Range town. These perspectives, presented primarily in the contemporary medical literature and the pages of The Weekly Mining Journal newspaper, illustrate a complex state of contention and conflict between Negaunee area residents and state health authorities. Investigation of community responses to the disease itself, epidemiological efforts by the State Board of Health and other entities, and the actions of local medical professionals complicates the story of typhoid in Negaunee, and raises important questions about the constraints of English-language reporting in uniquely multicultural communities, and the negligence of public health infrastructure and antagonization of “outsiders” in Negaunee, Michigan, in the late nineteenth century
Genetic Alterations Associated with Attention Deficit Hyperactivity Disorder
No full textAttention Deficit Hyperactivity Disorder (ADHD) is the most common neurodevelopmental disorder affecting children. Children with ADHD may have difficulty with maintaining focus and appropriate activity levels as well as controlling compulsive behaviors. Currently, the diagnostic criteria for ADHD is subjective and leads to frequent misdiagnosis and the subsequent use of prescription amphetamines which may lead to long term developmental cognitive alterations. Previous literature has identified ST3 Beta-Galactoside Alpha-2,3-Sialyltransferase 3 (ST3GAL3) as a possible genetic component underlying ADHD. This study uses Loop Mediated Isothermal Amplification (LAMP) to amplify the wild type of the ST3GAL3 gene in two groups of participants: one displaying ADHD characteristics as defined by the Adult ADHD Self-Report Scale (ASRS-v1.1) Symptom Checklist, and one that does not. The current study has two aims: (1) To replicate findings that show participants with ADHD test negative for ST3GAL3 and (2) To further investigate the influence of anxiety and depression, two highly comorbid disorders with ADHD
