Matching Items (10)
Filtering by
- All Subjects: kinesiology
- All Subjects: Remote Work
- Creators: Gaesser, Glenn
- Creators: Buman, Matthew P
Description
Eccentric muscle action (ECC) occurs when the force exerted by a working muscle is less than that of an outside resistance. This is characterized by muscle lengthening, despite actin-myosin crossbridge formation. Research has indicated that muscles acting eccentrically are capable of producing more force when compared to muscles acting concentrically. Further, research has shown ECC muscle actions may have different fatigue patterns that CON actions. The purpose of this study was to determine if a) ECC bench press yields greater strength than concentric (CON) as measured by one-repetition maximum (1RM), b) there is a difference between the number of repetitions that can be completed concentrically and eccentrically under the same relative intensities of 1RM (90%, 80%, 70%, 60%), c) a prediction model may be able to predict ECC 1RM from CON 1RM or CON repetitions to fatigue. For this study, 30 healthy males (age = 24.63 + 5.6 years) were tested for 1RM in CON and ECC bench press, as well as the number of repetitions they were able to complete at various intensities of mode-specific 1RM. A mechanical hoist was affixed to a gantry crane and placed over a standard weightlifting bench. The hoist was connected to 45lb plates that were loaded on a standard barbell, which allowed for mechanical raising and lowering of the barbell. For CON repetitions, the weight was mechanically lowered to the chest and the participant pressed it up. For ECC repetitions, the weight was mechanically raised and the participant lowered it. Paired t-tests showed that ECC 1RM was significantly (p < 0.05) greater than CON 1RM (ECC =255.17 + 68.37lbs, CON = 205.83 + 58.43lbs). There was a significant difference (p < 0.05) between the number of repetitions completed at 90% 1RM (CON = 4.57 + 2.21 repetitions, ECC = 7.67 + 3.24 repetitions). There were no differences in repetitions completed at any other intensity 1RM. CON 1RM and the number of repetitions completed with two different absolute loads (130-150lbs and 155-175lbs) concentrically and eccentrically were valid predictors of ECC 1RM. These data indicate that ECC actions yield increased force capabilities than CON actions, there is no difference in the rate of the fatigue, and ECC 1RM may be predicted from various CON tests.
ContributorsKelly, Stephen B., Jr (Author) / Hooker, Steven (Thesis advisor) / Brown, Lee (Committee member) / Buman, Matthew (Committee member) / Gaesser, Glenn (Committee member) / Swan, Pamela (Committee member) / Arizona State University (Publisher)
Created2013
Description
INTRODUCTION: Exercise performed at moderate to vigorous intensities has been shown to generate a post exercise hypotensive response. Whether this response is observed with very low exercise intensities is unclear. PURPOSE: To compare post physical activity ambulatory blood pressure (ABP) response to a single worksite walking day and a normal sedentary work day in pre-hypertensive adults. METHODS: Participants were 7 pre-hypertensive (127 + 8 mmHg / 83 + 8 mmHg) adults (3 male, 4 female, age = 42 + 12 yr) who participated in a randomized, cross-over study that included a control and a walking treatment. Only those who indicated regularly sitting at least 8 hours/day and no structured physical activity were enrolled. Treatment days were randomly assigned and were performed one week apart. Walking treatment consisted of periodically increasing walk time up to 2.5 hours over the course of an 8 hour work day on a walking workstation (Steelcase Company, Grand Rapids, MI). Walk speed was set at 1 mph. Participants wore an ambulatory blood pressure cuff (Oscar 2, SunTech Medical, Morrisville, NC) for 24-hours on both treatment days. Participants maintained normal daily activities on the control day. ABP data collected from 9:00 am until 10:00 pm of the same day were included in statistical analyses. Linear mixed models were used to detect differences in systolic (SBP) and diastolic blood pressure (DBP) by treatment condition over the whole day and post workday for the time periods between 4 -10 pm when participants were no longer at work. RESULTS:BP was significantly lower in response to the walking treatment compared to the control day (Mean SBP 126 +7 mmHg vs.124 +7 mmHg, p=.043; DBP 80 + 3 mmHg vs. 77 + 3 mmHg, p = 0.001 respectively). Post workday (4:00 to 10:00 pm) SBP decreased 3 mmHg (p=.017) and DBP decreased 4 mmHg (p<.001) following walking. CONCLUSION: Even low intensity exercise such as walking on a walking workstation is effective for significantly reducing acute BP when compared to a normal work day.
ContributorsZeigler, Zachary (Author) / Swan, Pamela (Thesis advisor) / Buman, Matthew (Committee member) / Gaesser, Glenn (Committee member) / Arizona State University (Publisher)
Created2013
Description
The health benefits of physical activity are widely accepted. Emerging research also indicates that sedentary behaviors can carry negative health consequences regardless of physical activity level. This dissertation explored four projects that examined measurement properties of physical activity and sedentary behavior monitors. Project one identified the oxygen costs of four other care activities in seventeen adults. Pushing a wheelchair and pushing a stroller were identified as moderate-intensity activities. Minutes spent engaged in these activities contribute towards meeting the 2008 Physical Activity Guidelines. Project two identified the oxygen costs of common cleaning activities in sixteen adults. Mopping a floor was identified as moderate-intensity physical activity, while cleaning a kitchen and cleaning a bathtub were identified as light-intensity physical activity. Minutes spent engaged in mopping a floor contributes towards meeting the 2008 Physical Activity Guidelines. Project three evaluated the differences in number of minutes spent in activity levels when utilizing different epoch lengths in accelerometry. A shorter epoch length (1-second, 5-seconds) accumulated significantly more minutes of sedentary behaviors than a longer epoch length (60-seconds). The longer epoch length also identified significantly more time engaged in light-intensity activities than the shorter epoch lengths. Future research needs to account for epoch length selection when conducting physical activity and sedentary behavior assessment. Project four investigated the accuracy of four activity monitors in assessing activities that were either sedentary behaviors or light-intensity physical activities. The ActiGraph GT3X+ assessed the activities least accurately, while the SenseWear Armband and ActivPAL assessed activities equally accurately. The monitor used to assess physical activity and sedentary behaviors may influence the accuracy of the measurement of a construct.
ContributorsMeckes, Nathanael (Author) / Ainsworth, Barbara E (Thesis advisor) / Belyea, Michael (Committee member) / Buman, Matthew (Committee member) / Gaesser, Glenn (Committee member) / Wharton, Christopher (Christopher Mack), 1977- (Committee member) / Arizona State University (Publisher)
Created2012
Description
The purpose of this dissertation was 1) to develop noninvasive strategies to assess skeletal muscle size, architecture, and composition in young and old adults (study #1) and 2) evaluate the impact of chemotherapeutic treatment on skeletal muscle satellite cells and capillaries (study #2). For study #1 ultrasound images were obtained from the quadriceps muscles of young (8 m, 8 f) and older (7 m, 5 f) participants on two occasions, separated by 5-15 days. Images were collected while the participants were both standing and supine, and were analyzed for muscle thickness, pennation angle, and echogenicity. In addition, test-retest reliability and ICCs were evaluated for each posture and when imaging sites remained marked or were re-measured from visit #1 to visit #2. Generally, in both younger and older adults muscle thickness was greater and echogenicity was lower in the anterior quadriceps when images were collected standing versus supine. Maintaining the imaging site between visits did not influence test re-test reliability for either age group. Older adults exhibited smaller muscle thickness, lower pennation angle and increased echogenicity. Further, variability for the use of ultrasound to determine muscle thickness and pennation angle was greater in older versus younger adults. Findings from study #1 highlight several methodological considerations for US-based assessment of skeletal muscle characteristics that should be considered for improving reproducibility and generalizability of US to assess skeletal muscle characteristics and function across the aging spectrum. This is particularly relevant given the emerging use of ultrasound to assess skeletal muscle characteristics in healthy and clinical populations. In the second study, ovariectomized female Sprague-Dawley rats were randomized to receive three bi-weekly intraperitoneal injections of the chemotherapeutic drug, Doxorubicin (DOX) (4mg/kg; cumulative dose 12mg/kg) or vehicle (VEH; saline). Animals were euthanized 5d following the last injection, and the soleus (SOL) and extensor digitorum longus (EDL) muscles were dissected and prepared for immunohistochemical and RT-qPCR analyses. Relative to VEH, cross-sectional area (CSA) of the SOL and EDL muscle fibers were 26% and 33% smaller, respectively, in DOX animals (P<0.05). In the SOL satellite cell and capillary densities were 39% and 35% lower, respectively, in DOX animals (P<0.05), whereas in the EDL satellite cell and capillary densities were unaffected by DOX administration (P>0.05). In the SOL MYF5 mRNA expression was increased in DOX animals (P<0.05), while in the EDL MGF mRNA expression was reduced in DOX animals (P<0.05). Chronic DOX administration is associated with reduced fiber size in multiple skeletal muscles, however DOX appears to impact the satellite cell and capillary densities in a muscle-specific manner. These findings from study #2 highlight that therapeutic targets to protect skeletal muscle from DOX may vary across muscles. Collectively, these findings 1) improve the ability to examine muscle size and function in younger and older adults, and 2) identify promising therapeutic targets to protect skeletal muscle from the harmful effects of chemotherapy treatment.
ContributorsD'Lugos, Andrew (Author) / Dickinson, Jared M (Thesis advisor) / Buman, Matthew P (Committee member) / Gaesser, Glenn A (Committee member) / Huentelman, Matthew J (Committee member) / Katsanos, Christos S (Committee member) / Arizona State University (Publisher)
Created2018
Description
The winter holiday period has been highlighted as a major risk period for weight gain due to excess caloric intake in the form of fat and sugar. Furthermore, diets high in fat and sugar have been implicated in the pathogenesis of diabetes and cardiovascular disease. Exercise aids in the prevention of weight/fat gain, and prevents deleterious changes in cardiometabolic function. The objective of this study was to examine the effects of a fat-sugar supplemented diet, with and without two different exercise training protocols, on body composition, glycemic control and other markers of cardiovascular disease in an at-risk population of overweight and obese males. Twenty-seven, healthy overweight/obese (BMI >25 kg/m2) males were fed 2 donuts per day, 6 days/week, for four weeks, while maintaining their current diet. In addition, all subjects were randomized to one of the following conditions: sedentary control, 1,000 kcal/week moderate-intensity continuous training (MICT) (50% of peak oxygen consumption), or 1,000 kcal/week high-intensity interval training (HIIT) (90-95% of peak heart rate). Supervised exercise training was performed 4 days/week on a cycle ergometer. Changes in body weight and composition, endothelial function, arterial stiffness, glycemic control, blood lipids and cardiorespiratory fitness (CRF) were assessed before and after the intervention. Body weight, lean mass and visceral fat increased significantly in HIIT (p<0.05) and were unchanged in MICT. There was a trend for a significant increase in body weight (p=0.07) and lean mass (p=0.11) in control. Glycemic control during the 2-h OGTT improved significantly in MICT and control, with no change in HIIT. Hepatic insulin resistance index (IRI) and 30-min insulin during the OGTT improved significantly after MICT and worsened following control (p=0.03), while HIIT was unchanged. CRF increased significantly in both HIIT and MICT, with no change in control (p<0.001). There were no significant changes in other markers of cardiovascular disease. The addition of a fat-sugar supplement (~14,500 kcal) over a 4-week period was not sufficient to induce deleterious changes in body composition and cardiometabolic health in overweight/obese young males. Exercise training did not afford overweight/obese males additional health benefits, with the exception of improvements in fitness and hepatic IRI.
ContributorsTucker, Wesley Jack (Author) / Gaesser, Glenn A (Thesis advisor) / Angadi, Siddhartha S (Committee member) / Whisner, Corrie M (Committee member) / Buman, Matthew P (Committee member) / Shaibi, Gabriel (Committee member) / Arizona State University (Publisher)
Created2016
Description
This thesis project focuses on the effects of technology issues in the remote work environment and analyzes them using Bolman and Deal’s four frames for organizational leadership (2017). Real life examples of problems and solutions from the North America Laundry & Home Care Finance department at Henkel are utilized. An introduction to the scope of remote work in 2020 and 2021 is presented, followed by a description of Henkel’s role, size, and structure. Technology issues that occur while working remotely are described and looked at through different employee perspectives and leadership frames. Solutions currently in use and potential solutions to reduce any negative effects of these problems are also given.
ContributorsBlake, Quinn Patricia (Author) / deLusé, Stephanie (Thesis director) / Martucci, Megan (Committee member) / Department of Information Systems (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Sedentary behavior and excessive weight gain have been proven to deteriorate many characteristics of muscle. Low muscular power and mass with excess fat mass are risk factors for a multitude of chronic conditions and functional disabilities. Resistance training (RT) has long been accepted as a rehabilitative method of maintaining or enhancing muscular performance and composition. There are various methods of determining lower extremity muscular power; however, isokinetic dynamometry has emerged as one of the most accurate and reliable methods in clinical and research settings. Likewise, various methods exist for determining muscle thickness; however, many of those methods are expensive and can expose individuals to radiation. Ultrasonography has emerged as an accurate and reliable alternative to measuring lower extremity muscle thickness. The objective of this study was to assess the effects of high-load/low-volume (HLLV) and low-load/high-volume (LLHV) RT on isokinetic knee extensor and flexor peak power in sedentary, RT naïve, overweight or obese men and women (Body Mass Index ≥ 25 kg/m2). Twenty-one subjects (n = 21) completed this study and were randomized into one of the following groups: control, a HLLV group that performed three sets of 5 repetitions for all exercises until volitional fatigue, and LLHV which performed three sets of 15 repetitions for all exercises until volitional fatigue. Subjects randomized to the RT groups performed full-body exercises routines on three non-consecutive days per week. Changes in isokinetic knee extensor and flexor peak power, quadriceps ultrasound muscle thickness, and right leg segment of dual-energy X-ray absorptiometry (DEXA) scans were measured before and after the 12-week RT intervention. There were no significant differences found in group, time or, group by time interactions for knee extensor and flexor peak power using isokinetic dynamometry. Other than a group interaction for vastus intermedius muscle thickness (P=0.008), no significant interactions or differences were observed for any of the other variables tested. Based on the results of this study, neither high- nor low-load RT resulted in significant differences between intervention groups in peak power of the knee extensors and flexor, muscle thickness changes of the vastus intermedius, and vastus lateralis and, in the right lower extremity segmented body composition measures using DEXA.
ContributorsSarellis, Sofoklis Demetrios (Author) / Ofori, Edward (Thesis advisor) / Angadi, Siddhartha (Committee member) / Gaesser, Glenn (Committee member) / Arizona State University (Publisher)
Created2020
Description
The health benefits of sufficient moderate-to-vigorous physical activity (MVPA) and sleep arewell-supported, with established links to decreased cancer risk, cardiometabolic health, all-cause mortality, and psychiatric symptomatology—including stress-related phenomena—for those who engage in 150 min MVPA/week and get at least 7 hours sleep/night. The latter outcome has rapidly become a major public health concern as our nation grapples with the impact of prolonged COVID-19 pandemic stress, which has triggered an onslaught of depression, anxiety, and PTSD throughout the population. Thus, while strategies to decrease stress are desperately needed, many Americans fall short of the very MVPA and sleep recommendations that have been shown to increase their capacity to cope. The purpose of the present study was to explore time-varying associations of MVPA and sleep with momentary perceived stress in adults forced to work from home due to the COVID-19 pandemic. Thirty remote-working adults (86.7% women; mean age 37.5 years, SD = 10.4 years) wore GENEActiv accelerometers on the wrist to capture MVPA and sleep data, and answered four Ecological Momentary Assessments (EMAs) per day regarding perceived stress, for fourteen days straight. Between- and within-person variations in MVPA, sleep quality rating (SQR), total sleep time (TST), and sleep efficiency (SE) were analyzed via multilevel models to determine whether certain changes in these parameters might lead to decreased perceived momentary stress. Between-person models revealed a significant negative effect of SQR on perceived stress levels the next day, beta= -.651, SE= .303, P= .04. Mean MVPA, TST, and SE were not significant inter-individual predictors of momentary stress. However, within persons, higher than normal MVPA (beta= -.005, SE= .002, P= .015), SQR (beta= -.277, SE= .071, P <.001), TST (beta= -.001, SE= .000, P = .004), and SE (beta= -.524, SE= .242, P = .031) were all associated with significant decreases in momentary stress, with individuals experiencing incremental benefits with each additional minute of MVPA and TST. In conclusion, daily fluctuations in MVPA and sleep habits correlate more strongly with momentary stress than do typical levels of these behaviors; this presents an attainable strategy for individuals to enhance their capacity to cope.
ContributorsLyons, Rachel Crosley (Author) / Buman, Matthew P (Thesis advisor) / Der Ananian, Cheryl (Committee member) / McCracken, Kasondra (Committee member) / Arizona State University (Publisher)
Created2021
Description
The Western Pattern diet has been characterized by having greater than 50 percent consumption coming from fat and sugar. This macronutrient allocation has been shown to have deleterious effects on endothelial function and metabolic markers of cardiovascular disease. Exercise has been shown to improve vascular reactivity and metabolic markers related to cardiovascular health. The objective of the study was to determine if exercise training can prevent the anticipated deleterious effects of a fat-sugar supplemented diet on endothelial function and blood markers of cardiovascular risk in young men. Twenty-one, healthy college-aged males were randomly assigned to either the doughnut + exercise or doughnut only groups. Both groups were fed 2 doughnuts per day, 6 days per week, for three weeks, while maintain their current diet. The exercise group completed 4 exercise training sessions per week consisting of 2 high intensity interval training bouts (up to 95% VO2peak) on a cycle ergometer and two moderate intensity, steady-state bouts (at 75% VO2peak) on a treadmill. Changes in body weight and composition, markers of endothelial function, oxidative stress, serum lipids, and blood glucose were measured in each group. As expected, cardiovascular fitness increased significantly in the doughnut-supplemented + exercise group as compared to the doughnut-supplemented (p=0.005). Significant increases in body weight (p=0.036), fat mass (p=0.013), and body fat percentage (p=0.014) were seen in the doughnut only group as compared to the doughnut + exercise group. The doughnut + exercise group showed significant improvements in fasting serum triglycerides (p=0.036), plasma insulin (p=0.039) and insulin sensitivity (HOMA; p=0.05) as compared to the doughnut only group. The doughnut + exercise group saw a significant improvement in nitric oxide availability whereas the doughnut only group experienced a significant decline (p=0.014). There were no significant changes in other markers. Despite the addition of a fat/sugar supplement of ~11,600 kcal over three weeks, 4 exercise sessions per week were sufficient to prevent a gain in body weight and fat mass, and also improve some measures of cardiometabolic risk. These results suggest that exercise may be necessary to prevent some adverse health outcomes associated with transient periods of excessive energy consumption.
ContributorsBlack, Laurie (Author) / Gaesser, Glenn (Thesis advisor) / Cataldo, Donna (Committee member) / Sweazea, Karen (Committee member) / Vega-Lopez, Sonia (Committee member) / Swan, Pamela (Committee member) / Arizona State University (Publisher)
Created2013
Description
Parkinson's Disease (PD) is a progressive neurodegenerative disorder that affects movement and balance control. Falls are a common and often debilitating consequence of PD, and reactive balance control is critical in preventing falls. This dissertation aimed to determine the adaptability and neural control of reactive balance responses in people with PD. Aim 1 investigated whether people with PD at risk for falls can improve their reactive balance responses through a 2-week, 6-session training protocol. The study found that reactive step training resulted in immediate and retained improvements in stepping, as measured by the anterior-posterior margin of stability (MOS), step length, and step latency during backward stepping. The second aim explored the neural mechanisms behind eliciting and learning reactive balance responses in PD. The study investigated the white matter (WM) correlates of reactive stepping and responsiveness to step training in PD. White matter was not significantly correlated with any baseline stepping outcomes. However, greater retention of step length was associated with increased fractional anisotropy (FA) within the left anterior corona radiata, left posterior thalamic radiation, and right and left superior longitudinal fasciculi. Lower radial diffusivity (RD) within the left posterior and anterior corona radiata were associated with retention of step latency improvements. These findings highlight the importance of WM microstructural integrity in motor learning and retention processes in PD. The third aim examined the role of the somatosensory system in reactive balance control in people with PD. The tactile and proprioceptive systems were perturbed using vibrotactile stimulation during backward feet-in-place balance responses. The results showed that tactile and proprioceptive stimulation had minimal impact on reactive balance responses. Small effects were observed for delayed tibialis anterior (TA) onsets with proprioceptive stimulation at a medium intensity. Overall, this dissertation provides insights into improving reactive balance responses and the underlying neural mechanisms in PD, which can potentially inform the development of targeted interventions to reduce falls in people with PD.
ContributorsMonaghan, Andrew S (Author) / Peterson, Daniel S (Thesis advisor) / Ofori, Edward (Committee member) / Daliri, Ayoub (Committee member) / Buman, Matthew P (Committee member) / Fling, Brett W (Committee member) / Arizona State University (Publisher)
Created2023