Kinesiology
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Item Embargo Snapping Hip Syndrome and Muscle Stiffness(2025-05-07) Job, TaylorMuscle stiffness may contribute to tendon stiffness and increase injury risk, specifically in the case of external snapping hip syndrome (ESHS). The objectives of this research are to determine if there is a correlation between iliotibial band (ITB) stiffness and tensor fascia latae (TFL) or gluteus maximus (GM) stiffness, to compare the ITB stiffness between dancers and controls, to compare the stiffness of the ITB in the dominant and non-dominant legs, and to compare the interaction between dance participation and symmetry of ITB stiffness from limb-to-limb. It is hypothesized that a stiffer TFL/GM will be correlated with a stiffer ITB, dancers will have a stiffer ITB than the control group, the dominant legs will have stiffer ITBs, and dancers will have greater differences in ITB stiffness between limbs. Shear wave elastography (SWE) will be used to determine how muscle stiffness correlates with ESHS. Participants were recruited through flyers and a university's science and dance club. There were 13 participants total, 8 dancers and 5 controls, none of them dropped out and no data had to be excluded. Images were taken of participants TFL, GM, and ITB. The data was analyzed by taking the average of the three images at each location and performing linear regressions to determine correlations between ITB and muscle stiffness. A series of independent samples and dependent samples paired t-tests were run to determine if there were any differences between the dancer and control group’s ITB, or between limbs within the dancer and control groups. TFL was found to have no correlation to the ITB while GM had a correlation. ITB stiffness between dancers and controls was not found to be statistically significant but there was a moderate effect size found. Control ITB from dominant to nondominant was found to be statistically significant while dancers were not, suggesting dancers have more limb-to-limb symmetry than controls.Item Restricted EPOC Substrate Metabolism AT/RT(2025-04-30) Bryant, TylerExcess post-exercise oxygen consumption (EPOC) represents the elevated oxygen intake following physical activity as the body restores itself to resting state, and it is influenced by both the intensity and modality of exercise. While EPOC has been well-documented, its role in substrate metabolism—particularly the differential utilization of fats and carbohydrates post-exercise—warrants further investigation. This study examines EPOC and substrate metabolism following distinct bouts of aerobic and resistance exercise in untrained individuals, aiming to compare the metabolic outcomes associated with each mode of training. Participants completed randomized sessions of aerobic and resistance exercise, with metabolic variables including oxygen consumption (VO₂), respiratory exchange ratio (RER), and resting energy expenditure (REE) measured before, during, and after exercise using indirect calorimetry. The findings are expected to contribute to the growing body of literature on how different forms of exercise affect energy expenditure and fuel usage during recovery, with implications for weight management and metabolic health interventions. Previous studies have shown that resistance exercise often leads to a prolonged EPOC with a greater reliance on lipid oxidation, while aerobic activity may induce shorter, yet immediate changes in metabolism (Borsheim & Bahr, 2003; Lyons et al., 2006). Understanding these distinctions is particularly relevant for developing targeted exercise prescriptions, especially in sedentary or metabolically compromised populations. This research will inform practitioners and exercise scientists of the practical metabolic outcomes of aerobic versus resistance training, potentially influencing exercise program design for health and performance goalsItem Restricted Young Adult Athletes’ Psychological Distress Differences by Level and Gender Identity(2025-02-28) Parrish, Maegan BThe young adult population has the highest percentage of new mental health diagnoses (Edwards & Froehle, 2023). Collegiate sports – Club and DI level – introduce additional demands and stressors, including heavy workloads, performance anxiety, and balancing time demands (Edwards et al., 2023; Peacock, 2022). Women student-athletes have shown a higher prevalence of psychological distress symptoms than men (Wolanin, et al., 2016). Researchers have primarily focused on psychological distress of NCAA athletes rather than Club athletes (Martin, et al., 2021). Therefore, this study explored the differences in psychological distress prevalence between athletes’ level and gender identity. Participants for this cross-sectional study included 459 student-athletes: 254 (54%) DI athletes (95 men; 159 women) and 207 Club athletes (83 men; 122 women). These student-athletes were asked to provide demographic information (e.g., gender identity, sport) while completing a mental health screening, including anxiety and depression symptomology levels measured, respectively, by the General Anxiety Disorder Questionnaire-2 (GAD-2) and Patient Health Questionnaire-2 (PHQ-2), which are, validated brief versions of the GAD-7 and PHQ-9. The total scores align with classifications for clinical (3-6), subclinical (2), and minimal (0-1) symptoms. The chi-square analyses were used to evaluate differences in the prevalence of clinical, subclinical, and minimal levels of depression and anxiety across athletic level and gender. There were no significant differences in prevalence by gender. By athlete level, there was a significantly higher prevalence of subclinical anxiety (26%) among DI athletes compared to Club athletes (7%). As well as a significantly higher prevalence of subclinical depression (18%) among DI athletes compared to Club athletes (6%). Though no other differences were significant, compared to Club athletes, nearly twice as many DI athletes had clinical level anxiety symptoms and three times as many had clinical level depression symptoms. Thus, it can be concluded there is a higher prevalence of psychological distress among DI athletes compared to their Club peers. This may illustrate the effect of having greater sports performance related stress and time constraints on students’ mental health symptoms. These findings support the increasing trend and requirements for NCAA DI Athletics Departments having embedded sport psychologists and mental health counselors.Item Restricted MOBILE SENSORIMOTOR INTEGRATION ASSESSMENT IN SOCCER PLAYERS(2025-05-01) Rollins, KyrstinBackground: The purpose of this study is to establish metrics that work in the field to promptly identify and evaluate the level of sensorimotor integration impairment incurred by repetitive sub-concussive loading (RSCL). Repeated head impacts, even without clinical symptoms of mTBI, can cause neurocognitive and neurophysiological impairments. In contact sports, repetitive sub-concussive impacts may lead to mTBI-like deficits, increasing the risk of neurological injury, cognitive decline, and CTE. One study found CTE in 41.4% of contact sport athletes under 30 at death. With many neurological injuries going undetected, developing a rapid, in-field assessment is crucial to prevent further damage. We hypothesize that the use of wireless sensorimotor integration measurements can be harnessed to objectively evaluate sensorimotor integration following periods of exposure to RSCL in the field. Methods: Our approach is to integrate wireless measures of postural control, oculomotor control, and cortical activation with virtual reality (VR) to provide a comprehensive assessment of sensorimotor integration function, independent of a lab setting, following a single period of exposure to RSCL. Twenty participants will be chosen who are ages 18-50 who currently play, or have played within the past two years, organized soccer with no diagnosed concussions within the past year and no lower extremity injuries within the past three months. These participants will be outfitted with a Pedar in-hoe pressure distribution and gTEC EEG systems after consent is obtained. They will then participate in the pretest using the wireless measures listed above. Next, the participants will take part in the RSCL exposure period. For the RSCL exposure period, soccer players will engage in a heading training protocol. Following completion of the heading protocol, participants will be re-tested using the same measures in the pre-test. Expected Results: We expect to see a difference in the sensorimotor integration measures before and after the RSCL exposure period. More specifically, we expect to see results similar to what is seen following concussion. The RSCL exposure data will help to develop a portable sensorimotor integration system for real-time impairment assessment after RSCL incidents in field settings. This system could help prevent neurological injury in sports, military, and other environments while also aiding in the evaluation of conditions like Parkinson’s disease and stroke.Item Embargo The effect of the cold pressor test on arterial wave reflection amplitude and timing in young healthy adults(East Carolina University, May 2025) Buckner, JanaeSympathoexcitatory stimuli, such as the cold pressor test (CPT), increase vascular resistance and brachial blood pressure. Cardiovascular responses to the CPT can predict cardiovascular risk. Previous research has demonstrated that surrogate measures of wave reflection (augmentation index) are increased during the CPT. However, this measure does not differentiate the effect of wave reflection amplitude and return time of the reflected wave. The purpose of this study was to test the hypothesis that the CPT would increase the amplitude of the backward pressure wave and result in an earlier return of wave reflection. Methods: Twelve non-obese, non-hypertensive, healthy adults between the ages 18 – 40 years participated. For the CPT, participants submerged their hand in ice water for three minutes. Brachial blood pressure and arterial pressure waves were measured via applanation tonometry at baseline and during the last minute of the CPT. Wave separation analysis was performed to determine the maximal amplitude of forward and backward pressure waves as well as the reflected wave transit time. Reflection magnitude was calculated as ratio of backward relative to forward pressure wave amplitude. Results: In agreement with previous research, there was a significant increase in aortic systolic and diastolic blood pressure, as well as augmentation index (all, p<0.05). The novel finding was that despite no changes in the forward pressure wave amplitude (28.16.8 vs. 28.19.4 mmHg, p=0.997), there was a significant increase in the backward pressure wave amplitude (10.82.7 vs. 12.85.4 mmHg, p=0.043) as well as reflection magnitude (386 vs. 455%, p=0.001). Lastly, there was a trend for a shortened reflected wave transit time (332.465 vs. 28860.1 ms, p=0.02). Conclusion: A sympathoexcitatory stimuli (i.e. CPT) in young healthy adults increased the amplitude of the backward pressure wave and tended to lead to an earlier arrival of wave reflections to the heart.Item Embargo Physical Activity Levels in Pregnant Black and White Women Who are Participating in An Exercise Intervention(East Carolina University, May 2025) McClendon, Aaliyah AntionettePhysical Activity Levels in Pregnant Black and White Women Who are Participating in An Exercise Intervention ABSTRACT Purpose: The primary purpose of this study is to investigate whether there are differences in physical activity levels between White and Black women during early and late pregnancy. A second purpose is to explore the attrition rates of White and Black women who participated in an exercise intervention during pregnancy. Methods: Healthy pregnant women between 18-40 years old, ≤16 weeks' gestation were recruited to participate in a supervise exercise clinical trial. The current study used a portion of data from this larger clinical trial. Participants wore an activity monitor (ActiGraph Link) on their non-dominate wrist for 7 consecutive days to measure physical activity. The women wore the activity monitor when they enrolled in the study (early pregnancy, ≤16 weeks), prior to but before the intervention started and during late pregnancy (36 weeks). The activity monitors were removed during any exercise sessions for the late pregnancy time point. Thus, the data reflects all non-intervention physical activity. Data were analyzed to determine daily minutes per day (min/d) spent in sedentary, light, moderate, and vigorous-intensity physical activity. T-tests were used to compare the time spent per day in different physical activity intensities between races at the early and late pregnancy time points. Attrition for this study was determined for those who dropped out before and during the intervention. More specifically, those who dropped out before the intervention were quantified as anyone whose gestation length was ≤ 16 weeks and who did not start any intervention sessions. The attrition occurring during the intervention was defined as women who no longer regularly attended the intervention sessions (<1 time per week for at least 2 consecutive weeks) during pregnancy. Attrition rates were calculated as frequencies for the pooled sample and then for White and Black women separately. Results: There was physical activity data from 99 pregnant women during early pregnancy (19 Blacks ,80 White). On average, participants were 30.48 ± 4.42 years old, with an overweight BMI of 28.18 ± 6.49 kg/m and wore the Link for 14 hours/day. In early pregnancy, prior to the intervention, the amount of time spent per day in sedentary, light, and moderate-intensity physical activity was similar between White and Black pregnant women (p>.05). Black and White pregnant women spent about 1 hour per day in sedentary behaviors, 9 hours a day in light physical activity, and about 4 hours per day in moderate intensity. In late pregnancy time point, there were 47 pregnant women (6 Blacks and 41 Whites) with physical activity data. On average, participants were 30.87 ± 4.39 years old with an obese BMI of 33.65 ± 10.27 kg/m2 and wore the Link for 13 hours/day. White and Black women spent similar amount of time during the day in sedentary behaviors and light-intensity physical activity (p>.05). The amount of time spent in sedentary behaviors were 5.45 ± 117.78 m/d, 46.04 ± 48.60 m/d and for light intensity physical activity it was 520.74 ± 118.88 m/d and 543.67 ± 101.31 m/d in the White and Black women, respectively. In contrast, during late pregnancy the White women spent more time in moderate-intensity physical activity during the day than the Black women during late pregnancy (White: 287.40± 83.59 min/d, Black: 205.71 ± 59.36 min/d; p=.02). Racial differences for vigorous-intensity physical activity were not examined during early and late pregnancy since only one participant engaged in this type of physical activity. Lastly, the attrition rates of the women participating in the exercise intervention were determined. Of the 99 women, 27% of the participants dropped out of the exercise intervention. When examining attrition rates by race, more Black women (42%) dropped out of the study than White women (23%). Attrition rates were highest between the 17 to 24-week gestation time point (52%), followed by the enrollment time point (33%). The main reason for discontinuing the intervention was time commitments (44%). Discussion: The findings of this study show that the intensity and amount of physical activity are similar between the two racial groups in early pregnancy. In contrast, during late pregnancy the time spent in moderate-intensity physical activity is lower in Black than White women, but it is similar for sedentary and light intensity. Attrition rates also show that overall that almost a third of the women stopped participating in the exercise intervention; however, more Black than White women dropped the study. The most common reason for discontinuing study participation is time commitments. Future research should examine physical activity levels in White and Black women through all trimesters of pregnancy to determine if they remain stable. Moreover, additional research is needed to examine the factors, impacting exercise intervention attrition rates in White and Black women.Item Open Access The Effect of Maternal Exercise Types on One Month Infant Resting Metabolic Rate(East Carolina University, May 2025) Clark, EthanPURPOSE: This thesis investigates the effects of maternal exercise types on infant resting metabolic rate (RMR). While extensive research supports the benefits of exercise in preventing chronic diseases such as cardiovascular disease and diabetes, there is limited understanding of how maternal exercise types affects infant whole-body metabolic outcomes. Given that the fetus is entirely dependent on maternal health and behavior, understanding how different types of prenatal exercise influence offspring metabolism is crucial. This study aims to examine the relationship between maternal exercise types, particularly resistance, aerobic, and combination training, and infant RMR. Previous research has primarily focused on maternal exercise effects on infant body composition, but the direct impact of maternal exercise types on RMR is unexplored. By addressing this gap, this research seeks to provide new insights into how prenatal exercise types can shape early metabolic function, potentially influencing long-term health outcomes. METHODS: This study examined the effects of prenatal exercise types on a one-month infant resting metabolic rate (RMR). Women ages 18-40 with singleton pregnancies, a pre-pregnancy BMI between 18.5-39.9 kg/m2, and gestational age <16 weeks were recruited. Participants were randomized to aerobic training (AT), combination (aerobic + resistance) training (CT), resistance training (RT), or an attention-control group. Exercise intensity was monitored via heart rate and the Borg scale. In the postnatal period, one-month infant RMR was measured using indirect calorimetry. Statistical analyses included ANOVA, Cohen’s d, and linear regression to assess group differences in RMR and explore predictors of one-month infant metabolism, respectively. RESULTS: Descriptive statistics provided an overview of participant characteristics, with no significant differences between exercise groups in demographic or perinatal variables (p > 0.05). ANOVA analyses revealed no differences in maternal or infant metrics, including BMI, birth weight, and growth parameters at one month (p > 0.05). Similarly, we found trends of differences in one-month infant resting metabolic rate (RMR) between exercise groups (RMR: F (3,24) = 2.463, p = 0.087). Moderate to large effect sizes, using Cohen’s D, were found in AT (D=0.75) and RT (D=0.68). Importantly, linear regression analysis identified significant increases in one-month infant RMR exposed to the resistance exercise in utero (p=0.0069), and significant decreases in one-month infants from women who performed aerobic training during pregnancy (p=0.0013), compared to the control. Additionally, pre-pregnancy BMI was positively associated with higher RMR (p=0.0006). The study limitations, mainly due to a small sample size, highlight the need for larger, more diverse research. CONCLUSION: This study suggests that prenatal exercise, specifically prenatal resistance exercise, augments infant RMR while aerobic training might attenuate infant RMR; these trends are worth further exploration. Overall, these findings support the potential benefits of resistance exercise during pregnancy for improved infant metabolic health.Item Open Access The Effects of Bat Grip Type on Baseball Hitting Performance(East Carolina University, December 2024) Langston, MaconINTRO: The success of a hitter for the longest time was defined by batting average but in today’s game success is more focused on performance metrics such as bat speed, attack angle, and exit speed. One aspect of hitting that has been shown to have a potential effect on performance is the way you grip the bat. The few common ways to grip the bat include the “conventional grip” (aka normal grip), choked up grip, and the “palmar hamate grip” (aka pinky or pinky off grip). The palmar hamate grip is becoming more popular across baseball as there is belief that it can increase performance. If there is some type of performance benefit, it would be valuable to investigate the mechanism or explanation for the improvement in performance. With the wrist being near the bat and slight movements potentially affecting the orientation of the bat, an analysis should be performed to see if changes in wrist kinematics could explain potential performance benefits from the palmar hamate grip. Prior research in regards to the palmar hamate grip and its effect on performance and wrist kinematics is limited. Additionally, a major limitation in prior research is not accounting for grip preference. PURPOSE: The main purpose of this study was to analyze the effect of the palmar hamate grip on baseball hitting performance in comparison to the conventional grip, accounting for grip preference. The secondary purpose of this study was to analyze the effect of the palmar hamate grip on wrist kinematics in comparison to the conventional grip, also accounting for grip preference. METHODS: Twenty-one high school and collegiate right-handed hitters (ages 16-22) participated and were separated into two groups based on grip preference (conventional, n = 14; palmar hamate, n = 7). The study consisted of two conditions: in the first, participants completed 5 maximal effort swings off a tee with their preferred grip; in the second, participants completed 5 maximal effort swings off a tee with their non preferred grip. Bat speed and attack angle were measured via Blast Motion sensor, exit speed was measured via Stalker Sport 2 radar gun, and smash factor was calculated by dividing exit speed by bat speed. Wrist kinematics were measured via 12 camera Qualisys 3D motion capture system. Wrist angle at contact, wrist range of motion (ROM), wrist angular velocity at contact, and maximum angular velocity in all three axes (x-flexion/extension, y-ulnar/radial deviation, z-pronation/supination) for both left and right wrists were calculated in V3D. RESULTS: Statistical significances were found for attack angle and smash factor but not for bat speed or exit speed. For attack angle, a significant difference was found between the palmar preferred and conventional preferred group in the preferred grip condition (8.57 ± 4.29° vs. 4.37 ± 4.13°, p < 0.05). Additionally, within the palmar preferred group a significant difference was found between the preferred and non-preferred grip conditions (8.57 ± 4.29° vs. 7.14 ± 5.00°, p < 0.05). For smash factor, the only significant difference found was between the preferred and non-preferred grip conditions within the conventional preferred group (1.16 ± 0.03 vs. 1.18 ± 0.03, p < 0.05), however this difference is not meaningful (d = 0.46). Wrist kinematic variables that showed significance included: left wrist flexion/extension angle at contact, left wrist pronation/supination angle at contact, left wrist flexion/extension ROM, left wrist ulnar/radial ROM, left wrist flexion/extension angular velocity at contact, and left wrist flexion/extension maximum velocity. However, the significance found for these variables were not clear in their effect on performance. No other significances were found for other wrist kinematic variables. CONCLUSION: The findings of this study indicate that the palmar hamate grip has some influence on attack angle, but not bat speed, exit speed, or smash factor. Also, the palmar hamate grip had no clear effect on wrist kinematics, suggesting the change in attack angle seen could potentially be due to other body kinematics. The more positive attack angle seen with the palmar preferred group compared to the conventional preferred group in the preferred grip condition is meaningful. Having a more positive attack angle helps in matching the bat path with the downward angle of the incoming pitch which maximizes the chance of solid contact and generates more optimal launch angle potentially leading to increased power and ball flight distance. Given that the changes in attack angle acutely were modest, the findings suggest long term training with the palmar hamate grip would be needed to improve attack angle.Item Open Access The Impact of Short-Term Mega Sporting Event Experiences on Student Learning(Sport Management Education Journal, 2024) Buenano, Andrea L.; Warner, Stacy; Moore, E. Whitney G.Short-term mega sporting events provide an opportunity for students to not only gain a memorable career experience but also enhance student skills and learning. However, very few (if any) researchers have explored students’ confidence related to key skills before and after such an event. Thus, the purpose of this study was to assess the effect of experiential learning at the National Football League’s 2023 Super Bowl LVII mega event on students’ learning outcomes. Students (N = 103) responded to an online survey distributed to assess their self-confidence across 18 learning-outcome skills covering problem solving, communication, sport-industry knowledge, and professional development. Each dependent-sample t test done to examine the students’ self-confidence with the individual learning outcome skills was significant (p < .001) and had meaningfully increased (Cohen’s d range: 0.47–0.97) from pre- to postevent. The results suggest that students can experience a notable increase in self-confidence when volunteering at a short-term mega sporting event. From a practical standpoint, the results provide sport management educators with strong evidence of the meaningful student learning related to problem solving, communication, sport-industry knowledge, and professional development that can occur with a single short-term mega-event experience.Item Embargo The Influence of Prenatal Exercise Mode on Maternal Cortisol Levels during Pregnancy(East Carolina University, July 2024) Smith, Savannah VictoriaBackground: Cortisol is essential for regulating metabolism, immune function, and stress response. During pregnancy, cortisol levels naturally rise to support fetal growth and development. However, elevated maternal cortisol levels are linked to adverse pregnancy outcomes, such as preeclampsia and preterm birth. While exercise is known to normalize cortisol levels in non-pregnant women, its impact during pregnancy remains unexplored. This study aims to examine the influence of different modes of exercise during pregnancy on maternal cortisol levels. Methods: This study consisted of women with singleton pregnancies, who were randomly assigned to one of four groups: aerobic (AE), resistance (RE), combination exercise (CE), or an attention control group (CON). Blood samples were collected at 16- and 36-weeks gestation to measure cortisol levels. Participant exercise sessions were supervised and tracked. Results: In all evaluated exercise types (AE, RE, and CE) the participants had normal levels of cortisol, normal birth outcomes, with no adverse pregnancy outcomes, and thus were deemed safe for pregnant women. The study observed different change patterns in cortisol levels from early to late pregnancy among exercising groups. At 16 weeks, all the maternal cortisol levels had a small effect size, which suggested the group values were similar. At 36 weeks, the AE and CE groups had a small effect size, which showed no difference between those values; but in the RE group, there was a large effect size, which showed a difference. The change scores of the maternal blood cortisol levels showed CON, RE, and CE groups increased from early to late pregnancy, however AE decreased from early to late pregnancy. Discussion: This study enhances the understanding of how exercise during pregnancy affects cortisol levels. While the RE group compared to the CON group showed a moderately strong increase at 36 weeks, this can be due to the large effect size. It provides insights into safe and beneficial exercise regimens, aiming to inform healthcare professionals and expecting mothers about the role of exercise in managing cortisol levels and promoting healthier pregnancy outcomes.Item Embargo The Effect of Maternal Exercise Mode on One-month Infant Motor Skills(East Carolina University, August 2024) Lilley, AshtonABSTRACT Purpose: To determine if the mode of exercise influences 1-month infants neuromotor skills. Methods: One hundred and seventy-two healthy, pregnant women between 18 and 40 years were randomly assigned to aerobic, resistance, a combination of aerobic and resistance exercise intervention or no exercise (control) group. Women in the exercise groups performed 50 min of moderate-intensity, supervised exercise, three times per week; those in control group maintained usual activity. Neuromotor skills were measured at 1 month of age using the Peabody Developmental Motor Scales, 2nd Edition (PDMS-2). Unpaired t-tests were used to compare infants’ PDMS-2 subtest percentiles, Gross Motor Quotients, and Gross Motor Quotient percentile between groups. Results: Infants of women with a pre-pregnancy BMI less than twenty-five in the aerobic and combination groups had higher PDMS-2 scores on 3 of the 4 variables analyzed relative to infants of the resistance group and nonexercisers. Infants of women with a pre-pregnancy BMI greater than twenty-five in the resistance group had higher PDMS-2 scores on 3 of the 4 variables analyzed relative to infants of the aerobic, combination, and nonexercising groups. Conclusion: Women who exercise during pregnancy may positively influence the neuromotor development for their infants. Earlier neuromotor development is correlated with higher activity rates in children. These findings could suggest that maternal exercise during pregnancy may reduce the risk of childhood obesity since physical activity is a modifiable risk factor for obesity. Key Words: CHILDHOOD OBESITY, MOTOR SKILLS, EXERCISE, PREGNANTItem Open Access The Relationship Between Smartphone Use, Social Support, and Mental Health in Collegiate Student-Athletes(East Carolina University, July 2024) Hohenstreiter, Trent AllanSmartphones have become increasingly prevalent in today's society. Additionally, there has been a rise in mental health problems, particularly among collegiate student-athletes, where 21-33% report depressive symptoms and 28-40% report anxiety symptoms (Cox et al., 2017; Davoren & Hwang, 2014; Glascock & Poliakova, n.d.; H. Li et al., 2017). Previous research has linked elevated smartphone use to the presence of these mental health issues (Barry et al., 2022; Dobrean & Pasarelu, 2016), yet little is known about potential mediators in this relationship. Perceived social support emerges as a potential mediator, as collegiate student-athletes often rely on informal support during mental health challenges (Habeeb et al., 2022). Moreover, athletes who report having more social support from informal sources (i.e., teammates and friends) also report fewer depression and anxiety symptoms (Hagiwara et al., 2021). However, smartphones may hinder the creation of social support networks (Przybylski & Weinstein, 2013), potentially exacerbating mental health problems among collegiate student-athletes. PURPOSE: The purpose of this study was to gain a better understanding of the underlying factors of the mental health problems collegiate student-athletes experience by examining perceived social support as a mediator in the relationship between smartphone use and mental health problems. METHODS: A sample of 101 collegiate student-athletes (32 males and 69 females) completed a survey measuring demographic factors, smartphone use (i.e., total screen time, social media screen time, and social media use during daily activities), perceived social support (i.e., esteem, emotional, informational, and tangible), and mental health (i.e., depression symptoms, anxiety symptoms, and stress). RESULTS: Bivariate correlations revealed a significant association between total screen time and depressive symptoms (r = .24, p < .05), while perceived social support was inversely related to mental health problems (r = -.26, p < .01). However, there were no significant relationships observed between any variable of smartphone use and perceived social support, including its subscales (i.e., esteem, emotional, informational, and tangible support) and perceived social support did not mediate the relationship between smartphone use and mental health problems. CONCLUSION: In line with previous research, the present study suggests that collegiate student-athletes with greater smartphone use are more likely to experience depressive symptoms. Additionally, when they perceive higher levels of social support, they tend to experience fewer mental health problems, including depressive and anxiety symptoms. These findings provide valuable insights for collegiate student-athletes and their athletic support staff, highlighting the importance of educating them about the detrimental effects of smartphone use on mental health, specifically depressive symptoms, and the potential benefits of creating strong socials support circles to reduce mental health problems.Item Open Access The Influence of Lower Extremity Muscle Fatigue on Baseball Pitching Biomechanics and Performance(East Carolina University, July 2024) Praski, JeremyTHE INFLUENCE OF LOWER EXTREMITY MUSCLE FATIGUE ON BASEBALL PITCHING BIOMECHANICS AND PERFORMANCE By Jeremy Praski July 2024 Director of Thesis: Nicholas Murray, PhD Major Department: Department of Kinesiology Baseball pitching is a complex and dynamic movement involving the lower extremities, trunk, and upper extremities with the goal of throwing the 145 g baseball toward home plate with maximal velocity and accuracy. Previous research has shown a link between elbow and shoulder injury with increased pitch volume, innings pitch in a calendar year, pitch type, and number of months pitched per year (21,32). According to Spotrac, which records the injured list of MLB players and their salaries while on the injured list, 18,369 days were missed by MLB pitchers on the injury list with a throwing-related injury in 2019, which translates into $318,667,058 lost by MLB clubs (35). To date, multiple studies that have investigated the influence of fatigue on pitching kinetics, kinematics, and muscle activation in the different phases of the pitching motion (2,3,8, 24,27,28). However, none of these studies consider the performance aspects of pitching accuracy as well as pitching velocity in a simulated baseball pitching performance in which joint kinematics and muscle fatigue are also recorded. PURPOSE: The purpose of this study is to determine how lower extremity fatigue with increased pitch count impacts a pitcher’s joint kinematics, muscle activation levels, and pitching performance so that coaches may better be able decide when to take a pitcher out of a game. METHODS: Eleven high school and collegiate pitchers (age: 16.67 0.86 years, height: 1.78 0.08 m, weight: 74.6 14.82 kg) with 11.4 1.59 years of experience participated, two of which had to be excluded due to EMG issues. Data were collected using Noraxon Ultium Lab EMG, IMU, and Ninox 120 video camera. EMG electrodes were equipped to muscle bellies of the stride leg (BF, GAST, SEMI, VL, VM) and drive leg (GM, VL, VM) muscles, with IMU’s being equipped to the stride leg (shank and thigh) and throwing shoulder (upper arm and forearm), along with C7. After a warmup, participants were equipped with EMG and performed MVIC testing, and then equipped with IMU. IMU were then calibrated, and participants were given the opportunity to thrown warmup pitches off the mound. Participants threw 14-18 pitch innings with fastball, offspeed, and breakingball randomized like a game scenario. Participants threw a minimum of 60 pitches with a maximum of 105 pitches thrown. After each inning, participant rating of perceived exertion (RPE) was recoded. RESULTS: Participants averaged 80 ± 13 total pitches and had a pitch velocity of (fastball 73.29 ± 5.98 mph, 73.76 ± 6.08 mph, offspeed 66.30 ± 5.98 mp, 66.41 ± 6.25 mph, and breakingball 62.81 ± 5.44 mph, 62.87 ± 5.63 mph) and pitch accuracy of (fastball 41.17 ± 25.48%, 37.63 ± 19.67%, offspeed 38.71 ± 30.87%, 28.77 ± 19.43%, and breakingball 30.24 ± 21.70%, 28.90 ± 20.86%) for the first and last innings respectively. Shoulder external rotation for the follow through phase of the pitching motion was significantly different from the first to last inning (p=0.03). There were no other variables that were found to be significantly different from first to last inning CONCLUSION: From the first to last inning, participant median frequency (Hz) for EMG did not significantly change, thus we do not believe that their lower extremity muscles were fatigued. However, we did notice that with no lower extremity fatigue, there were moderate Cohen’s D for effect size of the Wind Up and SFC pitching phase for throwing shoulder external rotation. This would indicate that although there was so significant difference, in the Wind Up and SFC phases there were moderate differences in the mean from first to last inning. Overall, this suggests that future studies should investigate how many pitches it takes for a pitcher to fatigue.Item Open Access THE EFFECTS OF HIP AND HAMSTRING MUSCLE STRENGTH ON DYNAMIC KNEE VALGUS AND JOINT TORQUES DURING A DOUBLE LEG DROP JUMP AND DOUBLE LEG SQUAT(East Carolina University, May 2024) Crawford, Lauren AshleyINTRODUCTION: Amongst the injuries that occur in the lower extremities, anterior cruciate ligament (ACL) injuries have been shown to be the most common lower extremity injury impacting the young adult and athletic populations on a year-to-year basis and these injuries are typically occurring via non-contact mechanisms. Insights into the mechanisms of these non-contact ACL injuries can give researchers guidance as to which direction prevention strategies should utilized rather than the implementation of broad neuromuscular and proprioceptive training protocols in use today. While knee valgus has been shown to be a risk factor for ACL, the role of proximal hip muscle strength and hamstring strength to prevent this knee valgus has not been established. PURPOSE: The purpose of this research was to determine the effect of hip and hamstring muscle strength on knee abduction angles and torques during double leg squats and drop jumps. METHODS: 20 healthy subjects were recruited and enrolled in the study. The Humac NORM dynamometer was used to assess muscle strength from the hip extensors, hip abductors, knee flexors, and knee extensors. Subjects then performed double leg squats and double leg drop jumps while motion analysis and force plate data were simultaneously collected. DATA REDUCTION: Lower extremity angles and torques were calculated from the motion and force plate data. Strength testing data (EMG, Humac Position, and Humac Torque) was collected from the Humac Norm Dynamometer. STATISTICAL APPROACH: We divided the overall group of participants into categories of strong vs. weak overall hip extensor and knee flexor strength. We then compared the knee abduction angles and joints torques between the two groups. We also explored the relationship between hip extensor and knee flexor strength on knee abduction angles and torques through a correlational analysis. RESULTS: Only the hip extensor showed significant correlations and significant differences between high vs low muscle strength with any of the knee angles or torques during the double leg drop jump task. Findings of this current investigation indicate that the strength values for only the hip extensor muscle group are indicative of a relationship between strength and knee valgus angles/torques. During the double leg drop jump task, the hip extensor strength group significantly predicted knee flexion angle at initial contact and knee flexion angle at peak vertical ground reaction force accounting for 26% and 24% of the variance respectively, leaving 74% and 76% of the variance unaccounted for by all other muscle strength variables. CONCLUSION: The current study found no statistically significant relationships between the maximum isokinetic strength between the knee extensor, knee flexor, and hip abductor muscle groups with the peak knee valgus angles and torques displayed during double leg drop jumps and squats. Findings of this current investigation indicate that the strength values for only the hip extensor muscle group are indicative of a relationship between muscle strength and knee valgus angles/torques based off a correlational analysis and stepwise regression.Item Open Access Family Members Impact on Physical Activity Levels and Enjoyment in Preschool-Aged Children(East Carolina University, July 2024) Bowers, MadisonPurpose: The primary purpose of this study was to investigate the impact mothers and older siblings have on the physical activity levels of preschoolers. Secondarily, the preschooler’s co-participation enjoyment was explored as well. Methods: A sample of 27 families (mother, sibling, and preschooler) participated in a one-time research visit. During the visit, there were two 20-minute play sessions: preschooler playing with mother and preschooler playing with older sibling independently. During the play sessions the participants were given a variety of sedentary and physical activities to choose from. Total physical activity counts during each play session were measured with an accelerometer. Enjoyment of physical activity co-participation was measured using a smiley face Likert scale. Data were analyzed using a paired t-test to compare total physical activity counts of the preschooler when playing with mother and when playing with older sibling. A paired t-test was also used to compare preschooler’s rating of enjoyment of physical activity co-participation between the mother and older sibling. Results: This study found that preschooler’s physical activity levels are similar when playing with their mothers (47,071.22 ± 19,653.04 counts per second) and older siblings (54,530.81 ± 20,791.38 counts per second) (p=.21). For enjoyment, there was no significant difference between the preschooler’s rating of enjoyment when playing with their mother or older sibling (4.76 ± .52 and 4.88 ± .86, respectively; p=.31). However, a higher percentage of preschoolers said they enjoyed playing with their mother (62%) more than their older sibling (38%) when asked. Discussion: The findings of this study show that both mothers and older siblings have a positive impact on preschoolers’ physical activity. This study further expands on the existing literature suggesting that families need to continue to be investigated as a determinate of physical activity for preschoolers. The novel findings on enjoyment of co-participation of physical activity contribute to the small amount of existing literature suggesting that enjoyment of co-participation needs to be further explored as a determinate of preschooler physical activity.Item Open Access PARENT AND COACH MOTIVATIONAL CLIMATE PROFILES AND ADOLESCENT ATHLETE GOAL ORIENTATION, ENJOYMENT, AND STRESS(East Carolina University, July 2024) Fuller, Stephanie Lynn KonopaskeQuality sport experiences can facilitate positive youth development and lead to increased sport retention. Social agents, including parents and coaches, play an important role in the quality of sport experiences through the motivational climates they create. Although both parents and coaches play independent roles, the motivational climates of social agents need to be considered collectively as athletes may perceive complementary or contradictory climates from parents and coaches. Social agents who establish mastery climates focus on self-referenced standards and define success in terms of improving ability. They emphasize the importance of effort, improvement, and skill mastery. Conversely, social agents who establish performance climates focus on norm-referenced standards and social comparison processes to define success in terms of doing better than others. They emphasize the importance of winning and competitive outcomes. Athlete perceptions of mastery climates have been associated with adaptive outcomes such as self-esteem and enjoyment, while perceptions of performance climates have been associated with more neutral to maladaptive outcomes such as immoral behavior and stress. Athlete perceptions of motivational climate have been linked to youth and adolescent athlete goal orientations (i.e., mastery or performance), enjoyment, and stress. However, the way in which these motivational climates simultaneously interact to affect young athletes is unknown. Therefore, the first purpose of this study is to identify profiles reflecting various combinations of parent and coach motivational climates using latent profile analysis. The second purpose is to examine whether profile differences exist in adolescent athlete goal orientations, stress, and enjoyment. Following IRB and athletic director/club director approval, 347 middle school-aged athletes completed surveys inquiring about perceived parent and coach motivational climate, goal orientations, stress, enjoyment, and parent involvement. Overall, athletes perceived moderate to high mastery climates and moderate to low performance climates, as well as complementary climates from parents and coaches. Athletes reported high task orientations, moderate ego orientations, moderate stress, high enjoyment, and high parent involvement. Latent profile analysis identified 5 profiles based on mastery and performance climates initiated by parents and coaches. Further analysis indicated that team type (i.e., school or club) predicted profile membership. Athletes who perceived a mastery climate reported higher mastery orientations and greater enjoyment, as well as higher parent involvement than athletes who perceived a performance climate. These athletes reported higher ego orientations, greater stress, and lower parent involvement. Athletes who perceived that their team was not achievement driven reported moderate mastery and performance climates from both parents and coaches, as well as moderate task/go orientation and stress, with lower enjoyment than other athletes. Finally, athletes who reported high mastery and performance climates from both parents and coaches reported high and ego orientations. These athletes found their sport experiences to be enjoyable, but also stressful. This research fills a void in the literature by examining the interplay of simultaneous motivational climates and achievement goal orientations. In addition, the results of this study provide evidence that adolescent sport organizations should emphasize communication and training for coaches and parents alike. In this way, they can facilitate positive sport experiences that are enjoyable and minimize stress, which ultimately may lead to positive youth development and sport retention.Item Open Access RELATIONSHIP BETWEEN MUSCLE COACTIVATION, AROUSAL, AND STABILITY METRICS DURING PERTURBED GAIT(East Carolina University, July 2024) Martin, ColinFalls are a health risk to people of all ages. One mechanism that may increase the chances of a fall is a feed-forward increased co-contraction, or stiffening strategy. Another mechanism that influences fall risk is perceived levels of arousal. High arousal can negatively affect rate of force development by increasing muscle co-contraction. We studied the potential relationship between arousal, co-contraction, and stability metrics to get a better understanding of the mechanism behind falls. This study found that there was a significant increase in co-contraction and margins of stability from the preperturbation to the perturbation step. However, there were weak to no correlations between arousal and either co-contraction or margins of stability. Therefore, perceived arousal doesn’t seem to be a strong predictor of co-contraction or fall risk.Item Embargo The Effect of Exercise Mode During Pregnancy on Maternal, Placental, and Cord Inflammatory Markers(East Carolina University, July 2024) Wisseman, Bree LynnABSTRACT Excessive inflammation during pregnancy is associated with adverse pregnancy outcomes. Specifically, increased pro-inflammatory tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), interleukin 1 beta (IL-1ß), interleukin-8 (IL-8), and c-reactive protein (CRP) have been associated with gestational diabetes, preeclampsia, intrauterine growth restriction, and preterm birth. Similarly, pathologies of the maternal-fetal interface, such as recurrent spontaneous abortion, are associated with high pro-inflammatory biomarkers. This also increases fetal exposure to high inflammation in utero, contributing to the increased risk of cardiometabolic and mental conditions later in life. In non-gravid adults, exercise is an effective method for reducing pro-inflammatory and increasing anti-inflammatory biomarkers, differing with exercise mode. Currently, no research has directly compared the effect of exercise modes during pregnancy on maternal, placental, and fetal inflammatory biomarkers. The purpose of this dissertation was to determine the effect of maternal aerobic, resistance, or combination (aerobic + resistance) exercise during pregnancy on maternal, placental, and cord inflammation. Samples from healthy pregnant women with singleton pregnancies that participated in a randomized control trial exercise intervention were obtained. The exercise intervention consisted of 150-minutes of moderate-intensity aerobic, resistance, or combination exercise per week from <16-wks gestation until delivery. First, we investigated the effect of exercise mode on inflammation in maternal plasma at enrollment (<16-wks) and 36-wks gestation. Second, we examined the concentration of inflammatory biomarkers in placental tissue. Third, cord blood was analyzed for inflammatory biomarkers. All studies utilized Luminex xMAP technology to quantify biomarker concentration. The second and third studies also identified protein and pathway differences with exercise using a label-free proteomics. Maternal, placental, and cord blood inflammatory biomarkers were similar between groups. However, these data revealed that other exercise metrics predicted inflammatory biomarker concentration. Specifically, increased weekly exercise duration predicted lower IL-6 and IL-8 and increased weekly exercise frequency predicted higher TNF-α in late pregnancy maternal plasma. Increased weekly exercise intensity predicted lower placental fibrinogen. Lastly, total exercise volume, exercise mode, and pre-pregnancy BMI predicted cord blood IL-6 and exercise mode and pre-pregnancy BMI predicted cord blood cortisol. Label-free proteomics revealed significantly different proteome landscapes in aerobic, resistance, and combination exercisers placental tissue and cord blood compared to controls. We identified multiple downregulated proteins in placentas of exercisers that related to inflammation and immunity. Similarly, there was a downregulation in cord blood pathways that related to innate and adaptive immunity, possibly indicating reduced downstream inflammatory biomarkers. Altogether the studies within this dissertation did not support our central hypothesis that exercise mode would differentially alter inflammatory biomarkers during pregnancy. However, our studies highlight the importance of monitoring all exercise metrics (e.g., frequency, intensity, time, type), as each related to changes in maternal, placental, and fetal inflammation. We were also able to identify other inflammatory proteins and pathways in placental tissue and cord blood, providing targets for future projects. Collectively, the studies within this dissertation support the safety of exercise during pregnancy, further emphasizing the possible benefits, regardless of exercise mode. The projects in this dissertation extend the knowledge on how antenatal exercise impacts inflammation during pregnancy, thus impacting maternal and infant health.Item Open Access Effect of Metformin Treatment in Gestational Diabetes Mellitus on Infant Mesenchymal Stem Cell Metabolism(East Carolina University, July 2024) Biagioni, Ericka M.Offspring born to women with gestational diabetes mellitus (GDM) experience long- and short-term health consequences that may be partially mitigated through effective and timely treatment of maternal hyperglycemia. Metformin is an effective anti-diabetic agent that is increasingly prescribed to pregnant women for the treatment of GDM. However, metformin readily crosses the placenta into fetal circulation and concerns regarding the potential impact on fetal development have not been adequately addressed. While investigations conducted in animal models have produced controversial findings, randomized controlled trials in humans have reported altered postnatal growth during infancy and childhood among offspring exposed to metformin in utero. Furthermore, the underlying causal mechanisms by which metformin exerts lasting effects on offspring remain unclear. Nevertheless, the use of human umbilical cord derived mesenchymal stem cells (MCSs) has recently gained recognition as a robust model for studying infant cellular outcomes, and current evidence demonstrates that outcome measures from infant MSCs are tightly correlated with longitudinal measures of infant clinical outcomes, such as adiposity measured from birth to 4-6 years of life; thus, infant MSCs present a unique opportunity to study infant cellular outcomes. To investigate the impact of in utero metformin on infant MSC energy metabolism, we collected infant MSCs from exclusively diet controlled (A1DM-MSCs) or metformin treated (Met-MSCs) GDM pregnancies. In aim one of this dissertation, we investigated the impact of in utero metformin exposure on infant MSC substrate oxidation and insulin action under basal conditions and in response to excess fatty acids using radiolabeled glucose, oleate, and palmitate tracers. Measurements of MSC lipid accumulation and mitochondrial content markers were also conducted, in addition to metformin concentrations in cord blood plasma samples. Met-MSCs displayed lower rates of oleate oxidation under basal conditions, compared to A1DM-MSC, despite no differences in mitochondrial content or lipid availability. Additionally, differences in oleate oxidation were no longer apparent under conditions of excess fatty acids. We also reported a large variability among cord blood plasma metformin concentrations, which did not associate with measures of maternal metformin dosing. In aim two of this dissertation, we examined the impact of in utero metformin exposure on infant MSC mitochondrial capacity and control of respiratory flux across physiologic energy demands in the presence of substrates specific to respiratory complex I (CI), CII, and fatty acid oxidation using cellular respirometry. We also investigated the relationship between metformin exposure measures and MSC mitochondrial outcomes. Met-MSCs exhibited lower mitochondrial maximal capacity and diminished CII-linked respiration and respiratory conductance compared to A1DM-MSCs. We also reported relationships between length of in utero metformin exposure and mitochondrial protein expression of CII and citrate synthase. Collectively, these data demonstrate that infant MSCs adaptively respond to in utero metformin exposure, as evident by the lasting effects observed in infant MSCs in the absence of metformin. These findings are clinically relevant and will help inform clinicians of the potential effects of prescribing metformin to pregnant women diagnosed with GDM on the developing fetus, thus increasing the level of care provided.Item Open Access Whole-Body Metabolic Flexibility is Discordant with Skeletal Muscle Metabolism(East Carolina University, July 2024) Krassovskaia, PolinaMetabolic disease continues to be a worldwide problem that affects all ages, sexes, and socioeconomic statuses. The development of metabolic disease is multifactorial with both genetic and environmental components. Because of this, interest has grown in the early identification of individuals susceptible towards the development of metabolic disease. Metabolic flexibility has gained standing as a metric of metabolic health and can be defined as the ability to appropriately adapt substrate utilization in response to substrate availability. Skeletal muscle (SkM) is a regulator of metabolic flexibility as it is the primary tissue responsible for post-prandial substrate handling, and metabolic inflexibility can be seen in the SkM of individuals with metabolic disease. As Western style diets are proportionally heavy in fats and implicated in the development of obesity, metabolic flexibility with lipids is of particular interest. High-fat diets (HFDs) are a common and successful approach for distinguishing differences in metabolic flexibility with lipids across populations. Some evidence exists for metabolic inflexibility in healthy, lean individuals, which suggests metabolic flexibility may be an innate component of SkM. Studies of individuals with overweight allow insight into the intrinsic characteristics of SkM that promote the development of metabolic disease, yet this population remains largely understudied. The current study aimed to assess metabolic flexibility in a population of healthy individuals with overweight with a 3-day HFD. In chapter 2, we show that the participants studied are sedentary, have overweight, and do not display evidence of dysglycemia or dyslipidemia. Participants did not differ in dietary habits before or during the diet. Metabolic flexibility was calculated as the change in SkM homogenate palmitate oxidation with the high-fat diet. Metabolically flexible individuals show almost a two-fold increase in palmitate oxidation with the diet, while inflexible individuals decrease oxidation by about one-third of pre-diet rates, and this occurs without any changes to pyruvate oxidation. Metabolic flexibility was not associated with skeletal muscle fiber type. The change in the respiratory quotient during a hyperinsulinemic-euglycemic clamp is a classical approach towards assessing metabolic flexibility; we found that this was not associated with metabolic flexibility when measured as the change in palmitate oxidation in homogenates with the diet. Additionally, flexible and inflexible participants did not differ in mitochondrial function. Taken together, this indicates that metabolic flexibility is an innate component of SkM and can be seen prior to any clinical evidence of metabolic disruption, and metabolic flexibility is not associated with either muscle fiber type or mitochondrial function. In chapter 3, we utilized primary human skeletal muscle stem cells (HSkMCs) of the same cohort of participants studied in chapter 2. We show that a 3-day HFD does not result in changes in HSkMC metabolism measured by substrate oxidation, glycogen synthesis, and protein content of mitochondrial markers and PGC1a. Cells were additionally incubated with a lipid cocktail for 24 hours, which has been shown to help distinguish differences in metabolic flexibility in HSkMCs. Even with lipid treatment, no effect of the HFD was seen. Although participants were stratified based off the change in palmitate oxidation seen in SkM homogenates, a main finding was that HSkMCs of flexible individuals show enhanced glucose metabolism seen as higher glucose oxidation efficiency. Interestingly, measures of HSkMC lipid metabolism did not associate with similar measures of homogenate lipid metabolism. Together, these data provide novel findings demonstrating that metabolic inflexibility is present in SkM prior to detection at the whole-body level and occurs without any clinical markers of metabolic disturbance.