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THE ASSOCIATION BETWEEN SELECTED LOWER EXTREMITY KINEMATIC VARIABLES AND FASTPITCH SOFTBALL SPEED - A PRELIMINARY STUDY
No full textThis preliminary study aimed to examine the association between selected lower extremity kinematic variables and pitch speed in fastpitch softball. The kinematic variables were chosen for their practical applicability, allowing coaches and athletes to assess and enhance performance using accessible tools. Five collegiate female softball pitchers volunteered for the study. Using the OpenCap system, five strike pitches from each participant were analysed. Due to the small sample size, Spearman’s rho analysis was employed. Results indicated significant associations between ball speed and normalised stride length (rs = –0.46, p = .022), and ball speed and normalised stride width (rs = 0.83, p \u3c .001). These findings suggest that specific lower extremity kinematic variables may influence pitch speed, warranting further investigation with a larger sample
KINEMATICAL ANALYSIS OF 135° CHANGE-OF-DIRECTION TECHNIQUES IN BASKETBALL
No full textChange of direction (COD) is a crucial movement in basketball, requiring athletes to decelerate, reorient, and reaccelerate efficiently. This study aimed to identify the COD techniques naturally adopted by basketball players during a pre-planned 135° CODs, and to compare the associated lower-limb kinematics and execution time. A total of 130 basketball players performed the V-cut test while wearing inertial measurement units. From the analysis, two COD techniques emerged: Side-Step and Split-Step. Side-Step was the predominant technique (72.1%) and demonstrated significantly shorter execution time per COD (p \u3c 0.001). Side-Step exhibited in the pivot leg greater hip flexion, knee internal rotation, and ankle dorsiflexion, while Split-Step showed higher movement variability and knee abduction. Side-Step appears to be the more efficient and stable COD strategy, offering faster COD execution
PLANTAR FASCIA STIFFNESS ACCOUNTS FOR INDIVIDUAL VARIANCE IN ITS STRAIN DURING HOPPING AT DIFFERENT FREQUENCIES IN FEMALES
No full textThe plantar fascia (PF) behaves like a spring during bouncing gait, whereas its strain is a potential risk factor for plantar fasciitis. PF strain in bouncing gait is determined theoretically by complex foot dynamics, involving numerous active and passive foot structures, but the determinants of its individual variability remain unclear. Here we show the high relevance of PF stiffness to its strain in hopping by 11 females. PF stiffness, assessed as shear wave velocity, correlates with peak PF strain in hopping at different frequencies (1.8, 2.6, 3.4 Hz). The variance accounted for increases with increasing hopping frequency (from 49 to 68%), indicating greater dependence of PF strain on its stiffness at higher frequencies. We suggest that practitioners improve PF mechanical properties by applying repetitive loads via bouncing gait to modulate PF strain and prevent foot injuries, including plantar fasciitis
Rolling the Dice: The History of Indian Reservation Gambling in the Upper Peninsula
Full text linkThe History of Indian reservation gambling in the Upper Peninsula is of a struggle for expectance from the state government, and of the people in the state. The positive economic gain of states being one of the reasons behind why the rise of the gaming industry needed to happen. With the passing of The Indian Gaming Regulatory Act helping the regulation of reservation gambling and breaking down what was not allowed under the act. Newspapers and an interview with Frederick Dakota, give a personal look into the rise of the gaming industry and the struggle that the people were having with coming to grip with the rise of gaming industry. The gains were not the only thing to come out of the rise of the gaming industry as the state is struggling with an increase in gambling addiction. The gaming industry looks like it will not slow down anytime in the near future
What Drives Gut Microbial Diversity and Community Structure Among Closely-Related Host Species?
Full text linkThe gut microbiome (GMB) of mammals hosts an important community of microbes that perform countless micro-ecosystem services for the host and are influenced by numerous factors including host physiology, environment, and phylogeny. Phylogeny may have a unique effect on GMB diversity and community structure (i.e., a GMB profile) via phylosymbiosis, a theory in which the evolution of hosts matches the evolution of their associated microbiota. Elucidating phylosymbiosis in mammals is difficult because multiple intrinsic and extrinsic factors collectively drive individual GMB variation. Thus, there is a need to simultaneously analyze the role of physiology, environment, and phylogeny on shaping host GMB profiles. I investigated this concept in 11 herbivore species across Etosha National Park (ENP), Namibia by extracting microbial DNA from fecal samples for 16S rRNA amplicon sequencing. I identified “core” bacterial taxa within herbivore species based on abundance and occurrence within samples. I discovered that certain bacterial taxa serve as environmental and physiological indicators in hosts. I found that GMB alpha diversity is influenced by sex and herbivore family, while GMB beta diversity is influenced by herbivore family and correlated with host divergence times in bovid species. However, ENP’s herbivore community did not exhibit phylosymbiosis, likely due to the influence of individual variation, dietary niche, and environment. This study fills knowledge gaps by quantifying the strength of multiple eco-evolutionary factors on GMB variation, and forms a foundation for future studies to incorporate GMB monitoring into conservation planning, which can serve as early warning signals for changes in host health
COMPARISON OF ISOKINETIC STRENGTH IN FEMALE VOLLEYBALL ATHLETES WITH AND WITHOUT KNEE PAIN
Full text linkPrevious literature indicates that male volleyball players with knee pain have lower quadriceps strength and higher hamstring/quadriceps-ratios (Chantrelle et al., 2022). This has not been investigated in females volleyball players yet. 24 women (71.8 ± 7.6 kg; 1.76± 0.6 m; 24 ± 3.5 years, 11 healthy/13 with chronic knee pain) were examined. The maximum strength and power of the quadriceps and hamstring muscles and their ratio in isokinetic measurement (90°/second) were determined using the ISOMED2000. Maximal quadriceps strength and power in isokinetic measurements is significantly lower in affected legs (
RETURN TO SPORT TESTING IN FOOTBALL: IMPLEMENTING SPORTSPECIFITY BY A MIXED REALITY APPLICATION
Full text linkThe purpose of this study was to identify, if a mixed reality gaming application (MOTUM XR), can be used for return to sport testing. Of specific interest was the influence of the standing position of the virtual non-contact player (left or right from the goal), on the movement pattern of the performing athlete. Kinematic and kinetic data were collected from nine healthy football players, who performed countermovement jumps and headers according to the game specification. For each jump condition three jumps were record. The headers showed significant movement adaptations with a shorter jump time (approx. 40%), increased vertical force peaks (between 25-42%) as well as less flexed knees (by 18-22°). The jumps that included heading for the ball, showed more sport specificity, the position of the thrower however had no significant influence on Limb Symmetry
THE DIFFERENCE IN VISUAL SEARCH STRATEGIES BETWEEN EXPERT AND NOVICE INSTRUCTOR IN EXERCISE MOVEMENT ASSESSMENT
Full text linkThe purpose of this study was to compare visual search strategies (fixations duration ratio on each segment, frequency of fixations and average of fixations duration) between expert and novice in exercise movement assessment using eye-tracking device. Sixteen experts with 5+ years of experience and seventeen novices with less than 1 year of experience were recruited. In eye-tracking experiment they watched three pre-recorded exercise movement assessments (squats in the frontal and sagittal planes and push-ups in the sagittal plane). There were no significant differences with fixations duration ratio on each segment, frequency of fixations and average of fixations duration. The results show doubts about evaluations by eyes and suggest motion analysis by biomechanics as alternatives
IMU JERK GRAB DETECTION IN SNOWBOARD FREESTYLE
Full text linkIn freestyle snowboarding the grab length during tricks is of high interest for judging and therefore also in coaching athletes. Purpose of this study was to assess the detectability of grabs in snowboard freestyle tricks using jerk data of a board-attached IMU. 117 tricks performed on a trampoline by eight elite national team riders and one coach were analysed. In 95 / 117 jumps different grab phases could be detected using the jerk. The start (median = 0.01s, IQR = 0.01s) and end (median = 0.01s, IQR = 0.01s) of a grab phase, defined as first and last touch of the hand to the board, was more accurately detected than a stable grab position, defined as a locked hand-board phase during the grab without any further hand motion, at the start (median = -0.03s, IQR = 0.04s) and end (median = 0.05s, IQR = 0.03s). Conclusively, the jerk could precisely detect grab phase events in 95 of 117 jumps and therefore qualifies as coaching tool. To be eligible as a judging tool further studies should try to improve detection reliability by using different parameters or technologies and investigate on-snow suitability