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From Heaven to Hell: A Reinterpretation of Comparison between Germany’s Airborne Fallschirmjäger Operations and the Allied Airborne Operation at Arnhem in World War II
Full text linkThis thesis examines the legacy of the German paratrooper corps and compares them to similar Allied operations during World War II. Relying on archival documents as well as 80 years of analysis by historians, the thesis argues that the overwhelming consensus among historians of the German Fallschirmjäger as a failed experiment is undeserved, since the pitfalls experienced during their operations pale in comparison to similar British operations. The German invasion of Crete in 1941 serves as the base example for Anglophone historians who favor the idea of German failure solely based on the number of German casualties. In reality, the Germans in all their operations demonstrated a remarkable flexibility which was able to offset increasing casualties, whereas the British in Holland demonstrated inflexibility in their own operation resulting in complete failure. This article seeks two objectives: first to clarify and present the German experiences from 1940-1941 in sufficient detail to underline the key aspects of airborne warfare, which the British deviated dramatically from. Secondly, is to contextualize both the German invasion of Crete and the British invasion of Holland within the grander scale of World War II airborne operations. The thesis interprets these operations as similar in their conception and implementation because of the shared realities and pitfalls of airborne operations but differ dramatically in their execution. This article does not seek to discredit the immense sacrifices from all fighting men in the 20th century but rather seeks to present a more complete historical understanding of the costliest conflict in history
SUSPENSION TRAINING EFFECTS ON LOW BACK PAIN AND FUNCTIONAL PEAK POWER FOLLOWING AN 8-WEEK TRAINING PROTOCOL
No full textPURPOSE: The purpose of this randomized exploratory study was to evaluate an 8-week strength training program using a fully off the ground suspension training apparatus in adults with LBP and its implication on 1) reducing LBP and 2) increasing functional sit-to-stand peak power (FSSPP) and quantifying changes following an 8-week training protocol when comparing the experimental (EXP) group (n = 4; 45.5±10.38 yrs) to the controlled (CON) group (n = 6; 45.5±14.02 yrs). METHODS: Ten male and female adults (BMI = 27.2±4.22; Ages 45.5±12.05 yrs) with LBP and pain intensity equal to or less than 40% in the Oswestry Low Back Pain Disability Questionnaire (OLBPQ) were qualified for inclusion in the study and were recruited from Murfreesboro, TN to participate in an 8-week strength training program (three visits/week, one hour/visit) exercising while suspended. The OLBPQ perceived pain scales was used to measure changes in back pain intensity; while the Tendo-Unit system was used to measure FSSPP across pre and post 8-week strength training program. Baseline difference between the two groups on the outcome variables were assessed using ANCOVA. All statistical significance was established at alpha level of p \u3c 0.05. RESULTS: Mean values were: OLBPQ pre-training (EXP17.00±10.39 %; CON 4.33±5.85 %), post-training (EXP 4.00±4.89 %; CON 9.00±10.41 %); while FSSPP pre-training (EXP 1323±410 Watts; CON 1498±387 Watts), post-training (EXP 1694±649 Watts; CON 1375±326 Watts). Significant decrease in LBP F(1,8) = 11.86, p = .009, η2 = 0.59, power = 0.85; and a significant increase in FSSPP F(1,7) = 6.37, p = .04, η2 = 0.48, power = 0.80 were related to the 8-week training protocol using the exercise suspension device. CONCLUSION: The eight-week strength training protocol showed a statistically significant difference in reducing LBP and increasing FSSPP in the EXP group when compared to the CON group. Benefits for evaluating this new fitness machine in this trial would enhance our understanding to its impact as an alternative modality on reducing LBP and improving overall health and wellbeing. This work could be an extension to potential research studies to explore in therapy, rehabilitation and fitness industries (e.g. its effect on sports specific skills, autism, ADHD and PTSD)
ELECTROMYOGRAPHIC ANALYSIS OF MULTIFIDUS MUSCLE ACTIVITY DURING THREE EXERCISES
No full textThe multifidus muscle is integral to spinal stability and posture control. To enhance rehabilitation and training programs, it is essential to understand the patterns of its activation across various exercises. PURPOSE: The purpose of this study was to analyze the electromyographic (EMG) activity of the multifidus muscle during three specific exercises: deadlifts, bird-dogs, and single-leg balance exercises, to determine which exercise most effectively activates this muscle. METHODOLOGY: Twenty adults (men: 9; women: 11; age: 24.7+2.1 yr; height: 167.9+10.8 cm; weight: 73.9+15.8 kg (mean+SD)) participated in the study. Surface EMG electrodes were placed bilaterally at the L4-L5 level after skin preparation. Deadlifts (5 reps at 50% body weight), bird-dog held for 10 sec on each side while holding a 2.27 kg weight in the outstretched hand, and single-leg stance held for 10 sec on each foot were performed under supervision in a randomized order. EMG data (max amplitude) were recorded with each session lasting ~15 minutes. Data were analyzed to compare muscle activation patterns across exercises. RESULTS: EMG activity showed significant (p\u3c0.05) differences across exercises with deadlifts inducing the highest mean muscle activation (0.949+0.623 mV), followed by bird-dog right (0.370+0.173 mV) and bird-dog left (0.352+0.161 mV). The single-leg balance exercises elicited the lowest mean muscle activations, both for the right (0.124+0.049 mV) and left sides (0.134+0.068 mV). There were no bilateral differences for any of the exercises. CONCLUSION: The multifidus muscle showed varying levels of activation across different exercises, with the highest activation during deadlifts and the lowest during single-leg balance tasks. The deadlifts elicited a significantly stronger muscle response compared to balance exercises, suggesting that weight-bearing exercises might be more effective for multifidus muscle activation. The findings suggest that rehabilitation programs that include deadlifts could potentially offer greater benefits for improving core stability and reducing back pain
INFLUENCE OF ARTERIAL STIFFNESS ON CEREBROVASCULAR RESPONSE TO EXERCISE IN INDIVDIUALS POST-STROKE
No full textArterial stiffness promotes the transmission of harmful pulsatile energy to the cerebrovasculature, causing microvascular damage and reduced cerebral blood flow. Post stroke, individuals exhibit increased arterial stiffness and are at an elevated risk for cerebrovascular decline. However, minimal research has explored the relationship between arterial stiffness and cerebral blood flow post stroke. PURPOSE: Examine the relationship between arterial stiffness and cerebral blood flow, as measured by middle cerebral artery blood velocity (MCAv), in individuals with stroke at rest and during exercise. METHODS: Participants, 20-85 years of age, 6 months to 5 years post stroke were included. We assessed arterial stiffness using carotid-femoral pulse wave velocity (PWV) for central arterial stiffness and waveform analysis for pulse wave mechanics: augmentation index (AIx), arterial pressure (AP). Transcranial doppler ultrasound was used to assess MCAv at rest and during moderate-intensity exercise. Heart rate was monitored to ensure exercise intensity. Data were sampled at 500 Hz and post-processed with a custom written MATLAB script to determine baseline (BL) MCAv, prior to exercise, and steady state (SS) MCAv during exercise. Linear regression was used to evaluate the relationship between MCAv, PWV, AIx, and AP. Data are presented as mean ± standard deviation. Statistical significance: = 0.05. RESULTS: Participants (n = 24) were 20±17 months post stroke, 62±13 years, 50% female. Average BL and SS MCAv were 41±13 and 49±16 cm/s, respectively. Arterial stiffness values were elevated, with an average PWV of 10±2 m/s, AIx 35±10%, and AP 16±7 mmHg. We observed significant relationships between BL MCAv, AIx (p = 0.05, = -0.52), and AP (p = 0.04, = -0.83). Significant relationships were also observed between SS MCAv and PWV (p = 0.02, = -3.58), AIx (p = 0.04, = -0.67), and AP (p = 0.02, = -1.12). CONCLUSION: Increased arterial stiffness negatively impacts cerebral blood velocity in individuals with stroke. As individuals post stroke are at an elevated risk for cerebrovascular decline, future research should explore interventions that target arterial stiffness improvement
A GREAT DEBATE: THE FEMALE ATHLETE TRIAD VS. RELATIVE ENERGY DEFICIENCY IN SPORT
No full textSince the mid-1990’s the Female Athlete Triad (the Triad) has been gaining momentum as an evidence-based physiological series of sequela, including impaired bone health and menstrual dysfunction, thus, impacting health and performance in sportswomen. The American College of Sports Medicine then endorsed this condition. However, within the past decade, this disorder has been criticized for being too narrow in scope and Relative Energy Deficiency in Sport (REDs) was born. REDs, mimics the Triad, with low energy availability (LEA) serving as the root cause for a broader series of systemic and organ-specific dysfunctions that apply to both male and female athletes. Since the original REDs consensus, the authors have updated their diagnostic protocol to a more comprehensive screening tool. However, drama has been building as the scientists who developed and fully back the Triad and those who have embraced REDs have been viewed as directly competing. This has quickly escalated from a professional dispute to open name-calling in publications, social media platforms, and conference presentations. This talk will briefly guide the audience through the history and scientific foundations of the Triad and REDs, providing evidence for and against each as the sole algorithm for athlete health and performance in a debate format, and lastly provide the most recent evidence for an alternative option
THE BURDEN OF BREATHING: HOW INCREASED WORK OF BREATHING REDUCES MUSCLE PERFUSION AND LIMITS EXERCISE TOLERANCE
No full textA recent series of studies have unveiled a potential link between higher work of breathing and abnormal muscle blood flow responses that contribute to exercise intolerance in patients with heart failure. These studies provide a compelling backdrop for the discussion of interwoven mechanisms that contribute to exercise intolerance and may provoke ideas beyond clinical populations. The physiological mechanisms that would be highlighted in this talk include: the work of breathing, sensory feedback, respiratory muscle blood flow, stroke volume, and leg muscle blood flow. More specifically, the proposed “big idea” is that increases in ventilation lead to elevated respiratory muscle work which limits increases in stroke volume and leg blood flow. The consequences of these responses will be discussed in the context of exercise performance. For example, although it may be straightforward to understand that limited leg muscle blood flow would limit exercise – how does this influence the sensory feedback mechanisms that might further drive increases in ventilation? Quickly, the “downward spiral” of events will be uncovered with heart failure as the primary clinical backdrop. A great deal of effort will be made to also provide context for these responses as the relate to other populations
PEAK MATCH RUNNING DEMANDS IN COLLEGIATE WOMEN’S SOCCER AND LACROSSE
No full textPeak match running demands, defined as distances covered at maximum relative speed over various time intervals, are critical for planning training and conditioning drills. While collegiate women’s soccer and lacrosse share similarities in match distances covered, the peak running demands for varying durations remain underexplored. PURPOSE: To compare peak match running demands over varying time durations in collegiate women’s soccer and lacrosse matches. METHODS: Collegiate women’s soccer (n = 10) athletes and women’s lacrosse (n = 10) athletes participated in this study. Wearable sensors collected distance covered during matches across an entire competitive season for each sport. Data were only included in field athletes that started in each match, excluding draw taker for lacrosse. Individual GPS files were analyzed to determine total distance covered over rolling durations lasting 30s, 1 minute, 2 minutes, 3 minutes, 5 minutes, and 10 minutes, with maximum relative speed (m·min-1) representing peak match running demand. A two-way repeated measures ANOVA was completed with Sidak correction for pairwise comparisons between sports for each duration (α=0.05). RESULTS: There was a significant sport by time duration interaction (p\u3c0.001). Lacrosse athletes demonstrated greater (p\u3c0.001) peak match running demands for durations lasting 30s (236 ± 37 m·min-1) compared to soccer athletes (216 ± 31 m·min-1). Conversely, soccer experienced higher demands (p\u3c0.001) over 10 minutes (112 ± 11 m·min-1) compared to lacrosse (90 ± 9 m·min-1). There were no significant differences between soccer and lacrosse demands for any other duration. CONCLUSIONS: Our analysis revealed that shorter intervals in lacrosse matches require higher running speeds, while longer durations in soccer demand greater sustained work rates. These differences are likely due to differences in rules of the game and styles of play between collegiate women’s soccer and lacrosse. Our findings can be utilized by performance professionals to optimize physical characteristics of athletes within these two sports
EVALUATING CHANGES IN, AND PREDICTORS OF, QUALITY STARTS AMONG PROFESSIONAL BASEBALL PITCHERS FROM 2015-2024
No full textIn Major League Baseball (MLB), a quality start (QS) is awarded to a starting pitcher who pitches at least six innings while allowing no more than three earned runs. Quality starts are used to evaluate starting pitcher performance, often expressed as a percentage of total starts (QS%). PURPOSE: This study examined changes in QSs and QS% in MLB from 2015 to 2024, excluding 2020 due to the COVID-19 pandemic. It also aimed to identify season-level key performance indicators (KPIs) associated with QS%. METHODS: Using publicly available data, a season-level dataset including performance metrics (e.g., strikeout rate) and pitch-specific variables (e.g., fastball velocity) was created for the 2015-2024 regular seasons. General linear models were used to assess changes in QSs and QS% over time. A linear mixed-model, with individual pitchers as random intercepts, (R2 = 0.710, LRT = 10.5, p \u3c .001) was used to examine the relationship between various season-level pitching statistics and QS%. RESULTS: Mean QSs decreased by 3.34 from 2015 to 2024 (t1096 = -5.03, p \u3c .001). Similarly, mean QS% declined from 54.5% in 2015 to 43.9% in 2024 (t1096 = -5.17, p \u3c .001). The linear mixed-model revealed that higher strikeout rate (F14,1010 = 65.0, β = 0.937, p \u3c .001), lower hard contact rate (F14,966 = 43.7, β = -0.498, p \u3c .001), lower pitch count per inning (F14,1075 = 532.54, β = -9.82, p \u3c .001), higher ground ball rate (F14,745 = 18.25, β = -0.234, p \u3c .001), lower pull contact rate (F14,1030 = 5.35, β = -0.183, p = .021), higher breaking ball velocity (F14,439 = 7.18, β = 0.233, p = .008), and induced vertical break (F14,443 = 4.84, β = -0.166, p = .028) were associated with increased QS%. CONCLUSION: While QSs declined from 2015 to 2019, a partial recovery was observed between 2021 and 2024. However, QSs and QS% in 2024 remained below 2015 levels, suggesting a long-term shift in starting pitcher performance. The significant associations between season-level pitching metrics and QS% suggest pitchers can improve the likelihood of a QS by increasing strikeouts, inducing more ground balls, limiting pull and hard contact, managing pitch counts efficiently, and enhancing breaking ball quality. Future research should investigate game-level data to further validate these findings or uncover alternative KPIs
PRACTICE AND EXPERIENCE OF DYNAMIC PERIODIZAITON AND PROGRAMMING FOR SUCCESSFUL MMA ATHLETES
No full textStrength and conditioning programs aim to optimize athletic performance and mitigate injury risks by developing physical and physiological characteristics through organized approaches. Mixed Martial Arts is an exciting sport that attracts competitors from diverse training backgrounds, experience levels, and regions of the world. However, limited information is available which discusses periodization and programming approaches that are dynamic enough to contribute to the successful development and performance of MMA athletes. Therefore, this presentation aims to bridge the gap between science, practice, and experience by providing insights into a strength and conditioning program that successfully developed three MMA champions over the course of one year
VOLUNTARY EXERCISE ENHANCES CIRCADAIN RHYTHMS AND CLOCK GENE EXPRESSION IN MICE
No full textCircadian rhythms are endogenous 24-hour cycles, regulated by clock genes throughout the body and synchronized by the suprachiasmatic nucleus (SCN). Disruptions to this rhythm have been shown to increase the risk of chronic diseases, making it essential to understand ways to reset or maintain a consistent circadian rhythm. Various periodic cues such as light stimuli have been shown to reset/entrain this rhythm, but less is known about the effects of exercise on the circadian clock. PURPOSE: To investigate the effect of voluntary wheel-running exercise on circadian rhythm, METHODS: this study used young adult male mice (4 months old; n=4) and aged male mice (18 months old; n=3). Over nine days, the activity of each mouse on its running wheel was monitored, and their circadian rhythms were subsequently analyzed and charted using ClockLab software. RESULTS: As expected, the young adult mice expressed stronger, more consolidated rhythms (amplitude =7800) as compared to aged males ( amplitude = 4000) when using the average periodogram amplitude as a metric of internal circadian strength. The younger mice also ran more, averaging ~4.2 km/day, while the older mice ran ~1 km/day. Brain samples were taken from each mouse, and immunohistochemistry was used to view clock gene expression in the SCN. The markers specifically analyzed for clock gene expression were arginine, cFOS, vasopressin and neuro-peptide Y. CONCLUSION: Results showed that clock gene expression in the SCN increased, suggesting that voluntary exercise enhances circadian rhythms in mice. Future studies will focus on the underlying mechanisms by which exercise affects circadian rhythm. Financial Support: 2P20GM121310-06 COBRE SENSORY BIOLOG