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EFFECT OF HALLUX VALGUS ON LOWER EXTREMITY KINEMATICS DURING BALLET MOVEMENTS
No full textThis study aimed to identify the specific motion characteristics associated with hallux valgus angles. Fourteen ballet dancers with hallux valgus performed the following three ballet movements in the 1st position: 1) standing for 5 seconds, 2) demi plié, and 3) sauté. Their movements were captured at 100 Hz using a motion-capture system. The relationship between the hallux valgus and foot joint angles, calculated using the multi-segment foot model, was tested using Pearson\u27s correlation coefficient. Dancers with large hallux valgus angles demonstrated inferior displacement of the midfoot in all three tasks. It was also observed that the knees were valgus in demi plié. As the effects of hallux valgus extend not only to the foot but also to the knee joint, it is necessary to assess the performance of the entire lower extremity when coaching dancers with hallux valgus
RUNNING-INDUCED FATIGUE INCREASES COORDINATION VARIABILITY, REGARDLESS OF RUNNING ABILITY
No full textWe examined the effect of fatigue on lower limb coordination variability (CV) and its relationship with running ability. Fifty recreational runners (♀= 25; 18-50 years) ran on a treadmill, at a speed 5% faster than their lactate threshold, until volitional exhaustion. Three-dimensional kinematic data were collected, and CV for sagittal hip-knee and knee-ankle couplings was calculated. One-dimensional repeated measures analysis via Statistical Parametric Mapping (SPM) revealed that CV increased in mid-stance and throughout swing in the final part of the run. Changes in CV were not predicted by VO2peak or 10 km performance, suggesting that the findings are relevant to a range of running populations. These results suggest that trends in CV could inform performance monitoring and represent a real-time proxy of fatigue
DIFFERENCES IN BACKSWING MECHANICS BETWEEN PROFESSIONAL AND AMATEUR GOLFERS
No full textThe purpose of this study was to investigate the swing mechanics of professional and amateur female golfers by analyzing biomechanical differences in their driver backswing. Motion capture and force plates were used to collect backswing data from 12 professionals and 12 amateurs. The backswing was segmented into five key events for analysis. Compared to amateur golfers, professional golfers generated greater horizontal ground reaction forces (Left Leg GRF X at MB: 5.12 ± 2.04 vs. 3.52 ± 1.43 %BW; BT: -6.97 ± 3.31 vs. -4.13 ± 2.91 %BW; Right Leg GRF X at BT: 10.52 ± 4.00 vs. 4.97 ± 3.04 %BW) and greater vertical ground reaction forces (Right Leg GRF Z at LB: 67.90 ± 6.95 vs. 75.09 ± 7.92 %BW; BT: 57.96 ± 9.59 vs. 71.42 ± 8.82 %BW). Additionally, they produced a higher left foot free moment during the backswing (LB: 0.61 ± 0.31 vs. 0.33 ± 0.19; BT: 0.71 [0.27–1.06] vs. 0.09 [0.00–0.31] %BW). This suggests that professional golfers perform more stable body rotation and store more energy for the downswing. In contrast, the amateur group exhibited greater left knee flexion at the MB event (28.56 ± 5.86° vs. 33.90 ± 6.74°) and increased center of mass (COM) movement (COM Y at LB: -3.73 ± 1.14 vs. -5.01 ± 1.20 cm; BT: -3.35 ± 1.08 vs. -4.83 ± 1.72 cm; COM Z at TB: 0.00 ± 0.26 vs. -0.35 ± 0.34 cm; MB: 0.17 ± 0.40 vs. -0.26 ± 0.55 cm) which may reduce the efficiency of free moment utilization during the backswing. These findings emphasize the importance of including kinetic variables—particularly ground reaction forces—in biomechanical assessments of the backswing, rather than focusing solely on kinematics
COMPARISON OF EXTERNAL INVERSION/EVERSION MOMENT BETWEEN BAREFOOT AND SHOD RUNNING
No full textWe aimed to illustrate the differences in the external inversion/eversion moment between barefoot and shod running under the same foot strike pattern and to identify the contributing factors. Fifteen healthy females participated and were instructed to run while keeping their habitual foot strike pattern in barefoot and shod conditions. From the three-dimensional coordinates of running (500 Hz) and the ground reaction force (1000 Hz), the foot external eversion/inversion moments were calculated. During the stance phase of running, the shod condition exhibited a significantly larger external inversion moment than the barefoot condition. The centre of pressure trajectory shifted medially in the shod condition, most likely explaining the emphasised external eversion moment seen in the shod condition. It can be suggested that the shoe sole structure induced this unique change
ENERGY FLOW ANALYSIS DURING MAXIMAL SPEED SPRINT RUNNING
No full textThe purpose of this study was to determine how mechanical energy is transferred, generated, and absorbed during maximal speed sprint running in semi-elite football players. To perform the segmental power analysis, we collected 3-D kinematics and ground reaction force data during maximum speed sprinting. During late swing, the thigh, shank, and foot showed net energy outflow (negative), indicating energy transfer to the pelvis/trunk or dissipated. During the first half of stance the hip was the prime generator while the knee and ankle absorbed energy. In the second half of stance, the hip transitioned to absorbing energy while the knee and ankle shifted to energy generation through to toe off. The hip and ankle joints were the primary sources of power generation, whereas the knee demonstrates a more complex absorption–generation transition, particularly around mid-stance
The Effects of Short-Term Rental Regulation on Neighborhoods in Traverse City, MI
Full text linkWith the increase in popularity of Short-Term Rentals (STRs) and the increase in housing and rental prices throughout the United States, this study aims to explore the effects STRs have on housing and rental prices in Traverse City, MI. Traverse City is a popular tourist area and has experienced significant price increases over the last decade. STRs have been a topic of regulation by many local units of government and the area lacks unified regulation. The study area is confined to two census block groups of adjacent neighborhoods that occupy different townships. The townships have two different approaches to STR regulation with one banning whole house STRs and no monitoring and the other allowing them by permit with density requirements and actively monitoring listing sites for violations. By comparing the increases in housing and rental prices and the number of active STR listings in the two neighborhoods, this study aims to explore the effects regulation has on compliance and housing cost. This study should provide a framework for implementing effective regulations that can be used as a primer for unifying regulations across the state of Michigan
The March of the Naples Soldier: A Look into the Spanish Flu Pandemic 1918-1920
Full text linkThis paper dives into the memory of Spanish Influenza from 1918 to 1920. It will analyze and deconstruct the fear caused or absent during that time and later in the records and literature. The comparison of the time of the Spanish Flu will be contrasted with the memory of the time period with the including of Pale Horse, Pale Rider, which was written in 1939. It will compare these two times and conclude with the recent COVID-19 pandemic from 2019 to 2021.
It was November 2019, and reports of a new respiratory disease from Wuhan, China, began to trickle in. Although it would start as a regional epidemic, it quickly escalated into a global pandemic by the middle of March 2020, bringing the modern world to a standstill. The unprecedented measures such as lockdowns, mask mandates, and a race to produce a vaccine, all aimed at controlling the spread of the virus, made it seem like we were living in a video game to prevent the eradication of humanity. This rare occurrence of a lethal pandemic was a shock to our seemingly invulnerable world of medicine. It produced an inconsistent response that led to civil disobedience, ranging from a lack of respect for mask mandates and conspiracy theories. This is not, however, the first modern pandemic. The first time our interconnected world, where people travel rapidly globally, turned against us was in 1918 with the forgotten Spanish Influenza Pandemic. The “Naples Soldier,” named after a popular opera show of the time, as it would be known to many parts of Europe, would jump around the world with maximum efficiency. The Spanish flu pandemic of 1918, although maybe forgotten and an infection attributed to the flu, would show a significant contrast among the reactions to the disease with the dissonance between the time of the Spanish Influenza and how it is remembered in records or literature of the time
Resistance, Adaptation, and Assimilation: Native American Responses to Christianization in the Great Lakes Region, 1800-1900
Full text linkAnalysis of the relationship between Native Americans and missionaries shifted from an early broad, sweeping praise of the missionaries, to overwhelming condemnation of their actions in the post Civil Rights political climate. Since the time of European contact, histories often fell into Hagiography; extolling the virtues of the missionaries, and their God-ordained work to save the soul of the perceived heathen Native. In the mind of many, the conversion of the Native was merely a natural result of the superiority of European-descended American culture. However, as a result of the Civil Rights Movement, a pivot away from lauditive analysis took place, and shifted toward seeing the missionaries as destructive forces of genocide. Both frameworks generally ignored a crucial aspect of the equation: Native agency. Indigenous people were written as objects that history simply happened to, rather than as people who participated in it. A push occurred, in recent years, toward recognizing Native Americans as active agents in their own history. They may not have willingly chosen the circumstances which beset them, but they did not sit idly by while missionaries Christianized their people. Instead, they resisted, adapted and assimilated in order to work within the system put upon them. This paper will analyze the threefold Native response as it pertains to the Great Lakes region of North America
ALTERED SPINOPELVIC KINEMATICS DIFFERENTIATE INDIVIDUALS WITH SYMPTOMATIC CAM FROM ASYMPTOMATIC CAM AND CONTROL GROUPS
No full textThis study investigated the influence of spinopelvic morphology and kinematics on symptom development in individuals with Cam-type femoroacetabular impingement (FAI), a condition where abnormal bone growth at the femoral head–neck junction leads to hip pain and degeneration. Thirty-two male participants were categorized into symptomatic Cam-FAI (n = 11), asymptomatic Cam (n = 10), and control groups (n = 11). Using weight-bearing biplanar imaging and 3D motion capture during high-flexion motor tasks, differences in spinopelvic clinical parameters and kinematics were analyzed. Results showed that symptomatic individuals exhibited higher pelvic incidence (51.4° ± 7.0), lower acetabular coverage (19.5° ± 5.8), in addition to increased lumbopelvic motion during squatting, suggesting compensatory mechanisms that may contribute to symptom onset. These findings underscore the need for dynamic, weight-bearing assessments to improve clinical evaluation and rehabilitation strategies in Cam-FAI populations
THE EFFECT OF CHANGING DEPTH AND SPEED ON GROUND REACTION FORCES DURING SQUAT
No full textThis study examined the combined effects of squat depth and speed on three-dimensional ground reaction force (GRF) patterns during bodyweight squats in 18 male participants. Imposed speed squats were about twice as fast as preferred speed, and peak knee flexion increased with depth: 99° (partial), 115° (half), and 130° (full). GRFs were measured with dual force plates and analyzed using one-dimensional statistical parametric mapping two-way repeated measures ANOVA. Slow-paced squats generated higher GRFs at the beginning and end of the movement, whereas fast tempo squats yielded a sharper vertical GRF during the bottom transition phase. Squat depth primarily affected horizontal GRFs: full squats produced more medial and anterior forces than shallower squats, although peak vertical GRF was similar across depths. Depth and tempo independently influenced GRF patterns. These findings inform exercise programming for both sports performance and rehabilitation