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Swimming Performance Post Blood Flow Restriction Training in Collegiate Swimmers
Get PDFPURPOSE: To determine if blood flow restriction (BFR) training improved performance and physiological factors in collegiate swimmers. METHODS: Participants (n=10) separated into 2 groups (control [CON] & experimental [OCC]), completed 9 supervised trainings within 3 weeks. Pre- and post-testing included: VO2max, Wingate, swim time trials (TT), strength, and DEXA. Training was identical except OCC underwent bilateral thigh BFR [blood pressure (BP) cuffs inflated 70-90% of systolic BP]. Training: treadmill walking 20 minutes (5x3-minutes at 3 mph, 5% grade, 1-minute rest), followed by bodyweight strength training (squats, lunges & step-ups). Pain levels (scale: 1-10) were taken after the second set of lunges, cuff inflated (PainA), and after all lunges, cuff deflated (PainB). Paired t-tests determined significant change within groups, independent t-tests determined significance between groups, ReANOVA determined significance of pain levels. RESULTS: Both groups increased 1 RM leg press CON: 18.0 ± 8.155 (kg) (p=0.008) and OCC: 15.200 ± 5.805 (p=0.004); 1 RM chest press (kg) increased significantly in OCC (p=0.031). Mean peak power (W/kg) increased 1.530 ± 2.389 (p=0.225) CON and 3.772 ± 3.088 OCC (p=0.052). Pain levels were significantly different between days (p=0.012), and between PainA vs PainB (p=0.008). No significant change in swimming TT, VO2max, total work, fatigue index, or body fat occurred. CONCLUSION: This BFR training program did not improve swimming performance but indicated adaptation to pain may occur
Estimating whole-body mechanical power in running by means of simulated inertial sensor signals
Get PDFThe Purpose of this study was to identify the potential of inertial sensor information to estimate whole-body mechanical power (WBP) in running. We recorded three-dimensional (3D) whole-body kinematic and kinetic data of eleven male subjects by means of optoelectronic motion capturing and an instrumented treadmill at speeds between 2.0 and 3.5 m/s. We simulated 3D acceleration and gyroscope signals for 15 segments of the whole body from marker trajectory data. We calculated one statistical model for each subject to estimate WBP from a set of 279 predictor variables derived from simulated sensor signals. Overall, WBP was estimated with root mean square errors between 4% and 20%. This highlights the potential of inertial sensor signals to estimate WBP. Nonetheless, in its current form, the method requires too many sensors for practical applications
ENERGY MEASURES ACROSS HOCKEY HELMET IMPACT LOCATIONS
Get PDFThis study examined the relationship between risk of head injury and energy loading across hockey helmet impact locations as another measure to assess helmet performance in reducing the risk of head injuries. A medium size NOCSAE headform instrumented with linear accelerometers was used to simulate dynamic impacts to the head during a free fall. The measured impact force was then used to determine energy loading and severity index. The results indicated that the energy loading on the helmet material accounts for 11.56% of the variance in predicting the risk of head injury across hockey helmet impact locations. This information becomes useful for researchers, coaches and helmet designers to better understand the material properties of helmets in energy loading and the role that the geometry of the helmet plays in minimizing the risk of traumatic brain injuries due to impact
Effects of Infanticide Risk and Timber Harvest on American Black Bear Space Use
Get PDFSpace use is an important aspect of bear ecology that maybe influenced by infanticide risk and timber harvest. I used generalized linear mixed models (GLMM) to determine if female American black bear (Ursus americanus) space use was consistent with avoidance behavior to reduce infanticide risk in the Upper Peninsula of Michigan during the 2009–2011 and 2013–2014 breeding seasons. Females with cubs occupied core areas and home ranges of similar size and relative probability of male use to females without cubs. Additionally, females with cubs did not reduce movements during times of day when male movements were greatest. Female black bears may exhibit variation in avoidance behavior based on the occurrence of infanticide. I used GLMM to estimate black bear use of stands harvested for timber production in the Escanaba River State Forest in Michigan during May–October 2009–2011. In general, bears used stands \u3c 100 ha more than larger stands, with some gender and seasonal differences. Bears used even-aged stands more than uneven-aged stands and stands \u3e 6 years old more than younger stands. However, bear use did not differ between deciduous stands and coniferous stands, or among land cover types except that grass/pasture and open water were avoided. Bear use was greater in areas farther from roads. Managing the amount of black bear resources appears possible by considering the number, size, type, and rotation schedule of timber harvests in deciduous and coniferous forests. However, increased human access resulting from road creation during timber harvest activities may reduce associated benefits
Who Do We Think We Are? A Tale of Mine Shafts, Caving Ground, Wilderness, Weed Whackers, Wolves and Fat Tire Bikes.
Get PDFThe Underground Railroad in the Upper Peninsula
Get PDFIn the three decades leading up to the American Civil War, there existed a loose network of people who helped slaves escape from the southern states, where slaveholding was legal, to the relative freedom and safety of the northern states and Canada. Called the Underground Railroad, this network was comprised mainly of free black people and Quakers. This essay explores the evidence to determine if the Underground Railroad was present in the Upper Peninsula
ISBS 2019 CONFERENCE PROCEEDINGS TITLE AND FOREWARD
Get PDFThe ISBS is an international society totally dedicated to biomechanics in sports, whose primary purposes are: To provide a forum for the exchange of ideas for sports biomechanics researchers, coaches and teachers. To bridge the gap between researchers and practitioners. To gather and disseminate information and materials on biomechanics in sports.
Published in the following proceedings are 125 papers across keynote, oral podium and poster presentations. There were at least two independent reviewers for each paper. The organising committee thanks all member of the scientific committee and the ISBS members who gave their time to undertake these reviews
SPIN OF A BATTED BALL TOWARD THE OPPOSITE FIELD IN BASEBALL
Get PDFThe purpose of this study was to investigate the spinning motion of a ball batted toward the opposite field in baseball. A pitching machine was used to launch the balls toward the bat, which was adjusted and tied up to hit the balls in the opposite field. The ball movements were recorded using three high-speed video cameras. The results indicated that the batted ball backspin and sidespin components correlate strongly with the launch elevation angles and launch horizontal angles, respectively. All the batted balls had a certain amount of sidespin components. The balls batted toward the opposite field experienced unavoidable horizontal Magnus force, resulting in curving. Thus, it is important to launch the balls with a larger velocity to hit a long ball toward the opposite field while comparing with the balls batted towards the same field with less sidespin components
BRAKING AND PROPULSIVE IMPULSES ACROSS A RANGE OF RUNNING SPEEDS IN UNILATERAL TRANSFEMORAL AMPUTEES
Get PDFBraking and propulsive ground reaction force impulses (GRIs) are mechanical parameters affecting the running performance. The purpose of this study was to determine the braking and propulsive GRIs across a range of speeds in unilateral transfemoral amputees. Ten unilateral transfemoral amputees ran on an instrumented treadmill at incremental speeds of 30%, 40%, 50%, 60%, and 70% of their maximum speed. At all given speeds, the braking GRI of affected limb was significantly smaller than unaffected limb; however, the propulsive GRIs were similar for both limbs. Consequently, the net anteroposterior GRI was positive in affected limb and negative in unaffected limb. These results suggest that the functional role of braking and propulsion is not the same between the limbs. Training for unilateral transfemoral amputees could focus on reducing the braking GRI of unaffected limb
DO GYMNASTS EXPERIENCE SYMMETRICAL LIMB LOADING WHEN PERFORMING FOUNDATION GYMNASTICS SKILLS?
Get PDFUneven asymmetrical landings in artistic gymnastics is considered a risk factor for injury. The aim of this research was to investigate if gymnasts experience asymmetrical upper and lower limb loading when performing foundation gymnastics skills on floor. Sixteen competitive level gymnasts (male= 8, female= 8) performed seven different gymnastics skills while wearing four inertial measurement units located bilaterally on the distal forearm and tibias. Every gymnastics skill showed significant inter-limb asymmetry (range z= -5.8, -6.0,