Purpose: Physical activity (PA) and mental health decline in winter. One potential mechanism to improve PA and mental health is dog walking. The purpose of this thesis is to examine the impact of dog walking on mental health and seasonal changes in PA. Methods: Participants (n=50; 34 dog owners, 16 non-dog owners) wore an Actigraph accelerometer and logged all PA (including dog walking) for one week per season. They also completed mental health surveys during their initial data collection week (baseline). Using baseline data, analyses were run to see if daily dog walkers (those who reported dog walking 6+ days/week; n=20) had more PA and better mental health than non-daily dog walkers (those who reported dog walking ≤5 days/week; n=26). Analyses were also run to see if summer daily dog walkers (n=15) better maintained their PA levels from summer to winter compared to summer non-daily dog walkers (n=21), and whether dog walking automaticity predicted PA and seasonal changes in PA. Results: Daily dog walkers took 2,900 more steps/day (p=0.01), but there was no difference in MVPA/week (p=.07) or in odds of meeting PA guidelines (p=0.25). There was no difference in perceived stress or depressive symptoms between groups (p=0.41 and 0.12, respectively). Being a summer daily dog walker did not predict a smaller change in PA from summer to winter (p=0.63). Finally, a higher dog walking automaticity was predictive of higher daily steps (p=0.02) but not meeting PA guidelines (p=0.15) or maintaining PA from summer to winter (p=0.63). Conclusion: In this study, daily dog walkers took more steps than non-daily dog walkers, but they did not have better mental health and still observed a decrease in PA from summer to winter. Future research with larger, more diverse samples is needed to understand the impact routine dog walking has on mental health and seasonal PA changes.

An important issue for sports scientists, coaches and athletes is an understanding of the factors within a running stride that can enhance or limit maximal running speed. Previous research has identified many sprint-related parameters as potential kinetic limiters of maximal Center of Mass velocity (Chapman and Caldwell, 1983b; Weyand et al., 2001). Bilateral asymmetry is present for many of these parameters during running; however the degree to which such asymmetries change as running speed increases is unknown. It was hypothesized that asymmetries in key sprinting parameters would be larger at maximal speed than all other tested speeds. Kinematics and kinetics were collected from nine female competitive speed and power athletes (age = 21 ±3 years, mass = 60.58 ±7.48 kg, height = 1.64 ±0.07 m) who completed maximal and submaximal sprinting trials on a force-instrumented treadmill. A repeated-measures ANOVA was completed for each parameter to examine the asymmetry differences across speed. The only parameter for which asymmetry was statistically greater (p<0.05) during maximal speed than all other speeds was effective vertical stiffness, in which the level of asymmetry increased incrementally with speed (r2=0.97). Therefore the hypothesis that asymmetries would increase with speed for all key parameters is rejected. Bilateral asymmetries in effective vertical stiffness appeared to be related to asymmetries in both vertical and A/P propulsive impulse at maximal speed. Furthermore, asymmetries in effective vertical stiffness may force runners to resort to a less stable and less coordinated gait, limiting their ability to further increase stride frequency, and thus limiting maximal speed.

The purposes of this dissertation were to examine the physical and technical demands of collegiate NCAA D-I male soccer players over the course of a competitive season. The following are the major findings of the dissertation: Study 1 – GPS normative data was calculated by position using data from 5 seasons (2017, 2018, 2019, 2021, 2022). GPS data was compared by position for 5 different GPS-derived metrics. No statistically significant differences were found in any field or lab testing data by position. Statistically significant relationships were found between physical match performance variables of TD and SPR with both YYIRT-1 and 20m sprint time, as well as between IMA-A and 20m sprint time. These results suggest that both the YYIRT-1 and the 20m sprint test is related to match performance in soccer players of this population. Study 2 – Normative data was provided for technical-tactical variables retrieved via WyScout®, a video analysis software used to tag technical actions of soccer games. Normative technical-tactical data are presented as mean ± SD. Statistically significant low to moderate negative correlations were found between total volume of technical actions and GPS variables. No statistically significant relationships were found between the strength-power lab tests measures and any of the total volume measures of technical actions. Statistically significant low to moderate correlations were found between speed and endurance field tests and total volume of technical actions. Study 3 – The relationship between training load and physical capabilities was examined by using appropriate testing. Bootstrapped ANOVA results showed statistically significant changes in pre and post testing for Static Jump Peak Power in the loaded condition. No other significant changes in lab testing results were found. Statistically significant changes in Yo-Yo Intermittent Recovery Test scores were found in pre- and post-testing. The relationship between GPS training load metrics and percentage of change in the administered test was found to be statistically significant between HSR distance and YYIRT distance, CMJ Peak Power and both TD and IMA-D. Physical capacity of NCAA D-I male soccer players seems to deteriorate over the season, but not differ statistically from baseline measurements. Physical changes could be context-dependent and a consequence of the specific training plan. Overall, soccer performance at the NCAA D-I level is multi-factorial and an analysis of the in-season demands of this population of athletes appears to yield some counterintuitive results.

This study assessed the effect of an eight-minute cycling intervention using varying intensities on exercise-induced hypoalgesia (EIH). Generally, current research examines EIH using protocols that last for more than 10 minutes and reach 75% of an individual's VO2 peak. The main objective of this study was to examine the effect of varying intensities on pressure pain threshold (PPT) and heat pain threshold (HPT) at the thigh and forearm, tested pre- and post-cycling intervention. Healthy male participants (n=16) performed a graded exercise test on a cycle ergometer to establish their peak power output (PPO). In subsequent visits, participants completed five different 8-minute cycling interventions, with intensities randomly assigned to one of three counterbalanced orders. HPT and PPT were applied to the thigh and forearm two times before and after each cycling intervention. Additionally, there was a notable effect of intensity on PPT in the thigh, with significant changes at intensities of 90% (p = 0.024) and 100% (p = 0.003). In the forearm, repeated measures ANOVA indicated that there was no significant interaction or main effect for intensity and time. Similarly, for HPT, the analysis did not show significant interaction or main effects for both intensity and location. This study was the first to examine EIH using an 8-minute cycling intervention on a cycling ergometer at individualized intensities. Higher intensity cycling sessions generated EIH locally in the thigh using PPT. This intervention appeared to target the nociceptors activated by mechanical, rather than thermal stimuli, further highlighting the multi-faceted nature of EIH. A short but high intensity cycling intervention may have clinical relevance, as it can provide an intervention to reduce localized pain immediately after exercise using a pressure pain stimulus.

This study analyzed the research on older adults and resistance training exercise and assessed effects on health span and lowering disability rates. A targeted search of the literature was employed using the following key words: sarcopenia, resistance training, hypertrophy, quality of life, disability, activities of daily living, strength training, falls, and functional strength. These were used to find articles that were relevant to the research. Articles were excluded if they focused on young athletes as they did not meet my research age group. Articles that focused on nutrition were also excluded as they pulled the focus away from the impact of resistance training on sarcopenia. The final exclusion that was made was to avoid any articles that made the focus on aerobic exercise as opposed to the focus being on resistance training. The age range of the participants was 60 years old to 93 years old. The results of the study saw that out 20 studies/sources cited shows that resistance training has been shown to increase the overall health, both mental and physical, of the 65+ population. Resistance training has been shown to increase functional capacity and ability to do activities of daily living, most importantly it reduces fall risk in the 65+ population. Finally, by helping to reduce fall risk and increasing overall health, resistance training has been shown to reduce the risk of disability in elderly adults. In conclusion, the risk of falls and serious consequences were reduced as the functional capacity and muscular strength of the elderly population increased. Overall, strength training has a positive effect on the elderly population and contributes to them maintaining their health, independence, and quality of life as long as possible.

Objectives To examine the relationship between Concussion Symptom Clusters (CSCs) and return-to-play time using a representative sample of U.S. college athletes with sports-related concussions. Background Recent evidence regarding concussion symptoms have been observed to be an important element of concussion severity, and potentially a predictor of return-to-play time. However, there is a paucity of data examining the associations between Concussion Symptom Clusters (CSCs) and return-to-play time in the U.S. college athlete population. Methods Data from the 2009-2010 to 2013-2014 academic years (n=1670) were obtained from the Datalys Center for Sports Injury and Prevention Inc. database. Exploratory factor analytic methods were applied, and the resulting factors were used in multinomial regression modeling to identify associations between CSCs and return-to-play time. ResultsA 4-factor solution accounted for 48.8% of the variance and included: audio-vestibular, somatic, amnesic, and affective factor structure. Audio-vestibular symptoms were associated with increased odds of prevented participation at 7-13 days, 14-29 days, greater than 30 days, and out for remainder of season, respectively (p Conclusion Specific CSCs were significantly associated with return-to-play time in college athletes, (p<0.05).

Despite the well-recognized benefits of exercise, Americans are gaining weight in astounding proportions and levels of physical activity are on the decline. The purpose of this study was to investigate a relationship between physical fitness, self-concept and sexual health. There is a dearth of knowledge on this relationship specifically in the context of sex-negative curricula, which is the dominate discourse in the United States. One hundred and thirty-three participants between the ages of 18 - 50 volunteered for fitness testing and data collection. Physical fitness was assessed through body fat, resting metabolic rate, cardiovascular endurance, muscular strength, muscular endurance and flexibility. Self-reported exercise was measured using the International Physical Activity Questionnaire. Self-concept was measured by the Six Factor Self-Concept Scale, which presented a total self-concept score and as six individual concepts of self (likability, morality, task accomplishment, giftedness, power and vulnerability). Additionally, sexual function was measured by Derogatis Interview for Sexual Functioning and presented as both an aggregate score and five separate constructs of sexual functioning (fantasy/cognition, arousal, orgasm, behavior/experience, and drive/desire). Questions pertaining to sexual partners, sex education, and demographic information were also included. The results of the General Linear Model indicated significant relationships between physical fitness, self-concept and total sexual functioning. The sexual behavior/experience of men was predicted by body fat percentage and flexibility. In women, behavior/experience was predicted by body fat percentage and arousal was predicted by cardiovascular endurance. Total self-concept was related to muscular endurance. When men were isolated in the analysis, likability was positively related to sexual behavior/experience, and task accomplishment was inversely related to sexual behavior/experience. In women, giftedness was related to cognition/fantasy, arousal, orgasm and total sexual functioning. No relationships were found between physical fitness and the number of sexual partners in men; however, both muscular strength and the power self-concept were significantly related to number of sexual partners in women. As a result of these findings, women may be inclined to exercise to improve arousal and sexual functioning. Furthermore, educators should note the findings of a positive relationship between physical and psychological health and sexual well-being because they provide support for the development and adoption of sex-positive curricula that incorporate potential benefits of sexual activity.

Objectives: We sought to examine the gender differences between low back pain (LBP) and muscle strengthening activity (MSA) in U.S. adults (≥20 years of age). Background: Low back pain is a well-known medical condition that has been shown to impact quality of life and professional productivity. It also adds to the financial burden of our healthcare system by augmenting medical treatment costs. Muscle strengthening activity is a recognized method to prevent and treat LBP. Studies analyzing the relationship between MSA and LBP by gender have produced mixed results. Methods: The sample (n=12,721) included participants in the 1999-2004 National Health and Nutrition Examination Survey (NHANES). Three categories of reported MSA participation were created: no MSA (referent group), some MSA (≥1 to/wk), and meeting the 2008 Department of Health and Human Services (DHHS) recommendation (>2 d/wk). The dependent variable was LBP. Results: Gender stratified analysis revealed significantly lower odds ratio of reporting LBP for women (OR 0.82; 95% CI 0.70-0.96, P=0.03) and men (OR 0.86; 95% CI 0.70-0.96, P=0.01) reporting volumes of MSA meeting the DHHS recommendation. Following adjustment for smoking, the odds ratio remained significant in women (P=0.03) but not in men (P=0.21). Conclusions: Men and women reporting volumes of MSA meeting the current DHHS recommendation were found to have lower odds of reporting LBP when compared to those reporting no MSA prior to adjustment for smoking. After adjustment for smoking, the association between MSA and LBP continued to be significant in females but in males. These findings suggest that smoking may be an important mediating factor that should be considered in LBP research.

Aortic stiffness is an independent risk factor that has prognostic value regarding future cardiovascular disease (CVD) events such as myocardial infarction, strokes, and heart failure. Although death rates due to coronary heart disease have declined in recent years, the leading global killer remains CVD and prevalence is still high. Understanding lifestyle contributors associated with aortic stiffness would provide the public with insight into targeting key health-related behaviors. The purpose of this observational study was to examine the association of physical activity, physical function, and dietary quality as independent factors contributing to aortic stiffness in apparently healthy middle aged men. Fifty-two men between the ages of 30 and 59 years were recruited to participate in this study, which required two visits to the Exercise Physiology Laboratory. Aortic stiffness was measured by aortic pulse wave velocity (aPWV) and was not associated with total daily step counts (r=-0.06; P=0.70). However, aortic stiffness was inversely associated with physical function, determined with the sitting-rising test score (r=-0.44; P<0.01) and inversely associated with relative muscular strength, determined with peak handgrip strength in both hands normalized to body mass (r=-0.41; P<0.01). Additionally, aortic stiffness was inversely associated with dietary quality, determined with the Healthy Eating Index score (r=0.51; P<0.01). In conclusion, key health-related behaviors in this study that explained a large percentage of the variation in aortic stiffness were physical function and dietary quality (Adj r²=0.47; SEE=0.634). Hence, optimizing overall musculoskeletal fitness by focusing on strength, balance, coordination, and flexibility in addition to greater adherence to the U.S. Dietary Guidelines are key lifestyle contributors associated with reduced CVD risk in otherwise healthy middle aged men.

Background: Obesity-induced alterations in biomechanics and muscle recruitment during activities of daily living, such as sit-to-stand (STS) are often attributed to increases in adipose tissue (AT) mass. Central or peripheral distribution of AT may differently affect biomechanics and muscle recruitment. Methods: Fifteen healthy, normal weight (BMI 22.4 ± 1.9 kg/m2, 24.1 ± 4.2 years) subjects volunteered. External loads equivalent to a 5 kg/m2 BMI increase were applied in three conditions: unloaded (UN), centrally loaded (CL), and peripherally loaded (PL). Subjects completed three successful STS movements in a backless chair under each load condition in random order. Motion analysis and lower extremity surface electromyography (EMG) were measured. Results: Compared to UN and CL, PL significantly increased support width during STS. PL also significantly increased maximum trunk flexion compared to CL. Peak and total VM EMG activity were significantly increased during CL, compared to UN and PL. During CL, peak VL EMG activity was significantly greater than UN. Conclusions: Central and peripheral weight gain induce different biomechanical adaptations during STS. Central weight gain increases knee extensor muscle activity during STS independent of biomechanical changes. In contrast, peripheral weight gain increases support width and trunk flexion with minimal EMG changes during STS.