Matching Items (12)
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- All Subjects: Exercise
- Creators: School of Nutrition and Health Promotion
- Resource Type: Text
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
This study examined the effect of an 8-week exercise intervention on functional exercise capacity in adolescents with Down syndrome (DS). Forty participants were randomly assigned to one of three groups: assisted cycling (ACT) (n = 17) where participants experienced at least a 35% increase in their voluntary cycling speed through the use of a motor, voluntary cycling (VC) (n = 15) where participants cycled at a self-selected cadence, and no cycling (NC) (n = 8) where participants did not participate in any cycling intervention. In each cycling intervention, each participant completed three, 30 minute cycling sessions per week for a total of eight weeks. The Six-Minute Walk Test (6MWT) was administered prior to and after the 8-week intervention in pre-test and post-test assessment sessions, respectively. Our hypothesis was somewhat supported in that functional exercise capacity improved after ACT as measured by an increase in total number of laps walked, total distance walked, and average walking speed during the 6MWT, when compared to VC or NC.
ContributorsCook, Megan Rey (Author) / Ringenbach, Shannon (Thesis director) / Huberty, Jennifer (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
This research study examined the effects of assisted cycling using a stationary recumbent bicycle that had an internal motor to help participants pedal at a desired cadence. The participants were either placed in an Assisted Cycling (AC), Voluntary Cycling (VC), or No Cycling (NC) intervention group. Those placed in the AC of VC groups then came to a laboratory setting 3 days a week for 8 weeks to cycle for 30 minutes. This research specifically analyzes the Vineland Adaptive Behavior Scale II to analyze the changes in daily living skills and maladaptive behaviors pre and post the exercise intervention. After analyzing the VABS II scores it was found that those in the VC intervention had statistically significant improvements in maladaptive behaviors. An interpretation of this finding is that the VC intervention had an increased heart rate over the span of the intervention and had a larger power output than those in the AC group. A limitation of this research is that it was a self-reported questionnaire that was given to the caregivers of the participant. The caregivers were not always controlled for, so in some cases two different caregivers were given the questionnaire for a single participant. A suggestion for future research would be to use the participant's mental age versus their chronological age when using the VABS-II and to use the Adaptive Behaviors Assessment System III (ABAS-III).
ContributorsJenkins, Cayla Marie (Author) / Ringenbach, Shannon (Thesis director) / Kulinna, Pamela (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
The purpose of this study was to examine the influence of Assisted Cycling Therapy (ACT) on depression in older adults with Down Syndrome (DS). We predicted that older adults with Down Syndrome would see an improvement in their depressive symptoms after ACT and Voluntary Cycling (VC). However, we predicted there would be a greater improvement in depressive symptoms after ACT in comparison to VC. Depression was measured using a modified version of the Children's Depression Inventory 2 (CDI 2) due to the low mental age of our participant population. Twenty-one older adults with DS were randomly assigned to one of three interventions, which took place over an eight-week period of time. Eleven older adults with DS completed the ACT intervention, which is stationary cycling on a recumbent bicycle with the assistance of a motor to maintain a cadence at least 35% greater than the rate of voluntary cycling. Nine participants completed the voluntary cycling intervention, where they cycled at a cadence of their choosing. One participant composed our no cycling control group. No intervention group reached results that achieved a conventional level of significance. However, there was a trend for depression to increase after 8 weeks throughout all three intervention groups. We did see a slightly slower regression of depression in the ACT group than the VC and control. Our results were discussed with respect to social and cognitive factors relevant to older adults with DS and the subjective nature of the CDI2. This study brings attention to the lack of accurate measures and standardized research methods created for populations with intellectual disabilities in regards to research.
ContributorsBeaman, Emily Kiernan (Author) / Ringenbach, Shannon (Thesis director) / Bosch, Pamela (Committee member) / Department of Management and Entrepreneurship (Contributor) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
The purpose of the study was to examine the effectiveness of two modes of exercise on depression in adolescents with Down syndrome (DS). Twelve participants randomly completed one of two exercise interventions. The interventions were: 1) Voluntary Cycling (VC), in which participants cycled at their self-selected pedaling rate 2) Assisted Cycling (AC), in which the participants' voluntary pedaling rates were augmented with a motor to ensure the maintenance of 80 rpms. In each intervention, the participant completed three cycling sessions each week for a total of eight weeks. Depression scores did decrease or improved after both AC and VC, but not significantly. There was a greater mean improvement for participants in the AC group than VC when analyzing total score and t-score. Future research will include a greater sample size and control group to reach significant results as well as try and reveal the mechanisms involved in these mental health improvements found after an acute bout of assisted cycling in adolescents with DS.
ContributorsTeslevich, Jennifer Lynn (Author) / Ringenbach, Shannon (Thesis director) / Kulinna, Pamela (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor) / Department of Psychology (Contributor)
Created2013-12
Description
Many individuals are not following healthy lifestyles as evidenced by the high obesity rates and poor physical activity levels. Many do not know how to eat healthy and exercise effectively, especially given busy schedules and no time to cook or go to the gym. However, people do spend a significant amount of time on their mobile device using social media. This outlet can potentially be used to inspire and teach individuals how to cook healthy simple meals, or find motivation to get off the couch for some exercise. In this study, strategies were identified that would increase the comments, likes, and followers of the investigator's Instagrams, which were designed to motivate followers to live a healthier lifestyle. Initially, 462 posts were assessed retrospectively to determine how the number of likes and comments were influenced by hashtags, category of posts (nutrition, fitness, or inspiration), and/or type of app, PicPlayPost, Instaframe, and the updated Instagram. These results were used in a 1-month prospective study to increase likes and followers to the investigator's Instagrams. In the retrospective study, it was determined that hashtags influenced the number of comments and likes across the categories and that the PicPlayPost app increased the likes in all categories. Hence, for the prospective study, the investigator wrote 1 nutrition and 1 fitness post daily for 28 days using a minimum of 15 hashtags per post. In addition, 3 nutrition posts and 3 fitness posts per week used the PicPlayPost app. This posting strategy increased the number of likes per post by 100%, and the number of followers increased from 369 to 1082 in one month. Interestingly, the nutrition posts received 27% more likes than the fitness posts, and the PicPlayPost app increased comments by 134%. In conclusion, the use of hashtags, PicPlayPost, and Instaframe apps increased the likes and comments on social media. These strategies may increase audience's attention on a certain topic and be used to improve individuals' lifestyles.
ContributorsTomasso, Bernice Grace (Author) / Johnston, Carol (Thesis director) / Dixon, Kathy (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2014-05
Description
Doxorubicin (DOX) is a cardiotoxic, anthracycline-based, anti-neoplastic agent that causes pathological cardiac remodeling due to altered protein expression associated with cardiotoxicity. DOX cardiotoxicity causes increased Akt phosphorylation, blunted AMPK phosphorylation and upregulated mTOR phosphorylation. Akt is activated by cellular stress and damage. AMPK is activated by increases in AMP and ADP concentrations and decreased ATP concentration. mTOR is active in cellular growth and remodeling. These proteins are cellular kinases with cascades that are influenced by one another. Exercise preconditioning may diminish the cardiotoxic effects on these proteins. Female, Ovariectomized Sprague-Dawley rats (N=33) were randomized to: Exercise+DOX (EX+DOX, n=9); Exercise+Vehicle (EX+VEH, n=8); Sedentary+DOX (SED+DOX, n=8); and Sedentary+Vehicle (SED+VEH, n=8) groups. DOX (4mg/kg) or VEH (saline) intraperitoneal injections were administered bi-weekly (cumulative dose of 12mg/kg). VEH animals received body weight matched volumes of saline based on dosing in animals receiving DOX. Exercise (EX) animals underwent high intensity (85-95% VO2 peak) interval training (HIIT) (4x4 min bouts) separated by low intensity (50-60% VO2max) intervals (2 min bouts) 5 days per week. Exercise began 1 week prior to the first injection and was continued throughout the study. Rats were euthanized 5 days after the last injection. Left ventricular tissue was isolated, processed into lysate and used for western blot analyses [2x2 ANOVA; (α=0.05)]. DOX induced significant phosphorylation of Akt and mTOR (p=0.035; p=0.032) only in SED+DOX rats, but unchanged in EX+DOX rats. No significant differences (p=0.374) in AMPK phosphorylation were observed between groups. Exercise Preconditioning prevents some DOX-induced changes in the cardiac mTOR signaling pathway implicated in pathological remodeling.
ContributorsPanknin, Timothy M (Author) / Angadi, Siddhartha (Thesis director) / Sweazea, Karen (Committee member) / Dickinson, Jared (Committee member) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The purpose of this study was to investigate the effects of high intensity interval exercise (HIIE) on postprandial fat and carbohydrate oxidation after a high carbohydrate and fat meal in healthy adults. It was hypothesized that the HIIE would result in greater postprandial fat oxidation than the control condition. Three subjects, all non-obese (BMI<30) from the ages of 21-24, underwent a 3 visit protocol. The first visit was to establish a VO2 max (on a cycle ergometer) and the following two were randomized between a control and exercise condition. The exercise condition was comprised of one hour rest to provide baseline data, followed by a 1 minute on (90-95% HR max), one minute off high intensity interval protocol on a cycle ergometer. This was conducted until the same amount of kcal as the standard meal (490 kcal. 250 kcal snickers and 240 kcal sprite) was expended. After the exercise, the participant waited for one hour to minimize the effects of the excess post-exercise oxygen consumption (EPOC) period, and then consumed the meal. Once this was completed, VO2 was measured for the last 10 minutes of every 30 minutes for a full 5 hours postprandial. The same methodology was employed in the control condition except for the exercise protocol. Results showed a significantly greater fat oxidation in the HIIE condition, oxidizing 28 grams, 32 grams, and 27 grams of fat in each of the 3 subjects compared to 14, 16, and 17 grams in the control condition respectively. This supports the notion that HIIE results in greater postprandial fat oxidation compared to seated rest.
ContributorsSeroka, Zachary Steven (Author) / Gaesser, Glenn (Thesis director) / Angadi, Siddhartha (Committee member) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
It is broadly accepted that physical activity provides substantial health benefits. Despite strong evidence, approximately 60% to 95% of US adults are insufficiently active to obtain these health benefits. This dissertation explored five projects that examined the measurement properties and methodology for a variety of physical activity assessment methods. Project one identified validity evidence for the new MyWellness Key accelerometer in sixteen adults. The MyWellness Key demonstrated acceptable validity evidence when compared to a criterion accelerometer during graded treadmill walking and in free-living settings. This supports the use of the MyWellness Key accelerometer to measure physical activity. Project two evaluated validity (study 1) and test-retest reliability evidence (study 2) of the Global Physical Activity Questionnaire (GPAQ) in a two part study. The GPAQ was compared to direct and indirect criterion measures including object and subjective physical activity instruments. These data provided preliminary validity and reliability evidence for the GPAQ that support its use to assess physical activity. Project three investigated the optimal h.d-1 of accelerometer wear time needed to assess daily physical activity. Using a semi-simulation approach, data from 124 participants were used to compare 10-13 h.d-1 to the criterion 14 h.d-1. This study suggested that a minimum accelerometer wear time of 13 h.d-1 is needed to provide a valid measure of daily physical activity. Project four evaluated validity and reliability evidence of a novel method (Movement and Activity in Physical Space [MAPS] score) that combines accelerometer and GPS data to assess person-environment interactions. Seventy-five healthy adults wore an accelerometer and GPS receiver for three days to provide MAPS scores. This study provided evidence for use of a MAPS score for future research and clinical use. Project five used accelerometer data from 1,000 participants from the 2005-2006 National Health and Nutrition Examination Study. A semi-simulation approach was used to assess the effect of accelerometer wear time (10-14 h.d-1) on physical activity data. These data showed wearing for 12 h.d-1 or less may underestimate time spent in various intensities of physical activity.
ContributorsHerrmann, Stephen (Author) / Ainsworth, Barbara (Thesis advisor) / Gaesser, Glenn (Committee member) / Der Ananian, Cheryl (Committee member) / Kang, Minsoo (Committee member) / Vega-Lopez, Sonia (Committee member) / Arizona State University (Publisher)
Created2011
Description
The purpose of this study was to determine if there were asymmetries in ground reaction forces (GRF) between dancers and non-dancers, and to see the effect of GRF on external (ER) and internal rotator (IR) strength. Subjects performed double- and single-legged jumps on a force plate with a motion capture marker system attached at anatomical landmarks, and then had strength and range of motion (ROM) of their internal and external rotators tested along at degrees of hip flexion. There were no significant differences in GRF between legs for all subjects involved. However, stronger hip ER was negatively correlated with vertical GRF (z-axis), positively correlated with anteroposterior (y-axis) GRF, and higher mediolateral (x-axis) GRF from double-leg trials was positively correlated with knee abduction. Thus, future studies should further investigate GRF broken into axial components as well as the time to peak GRF to determine any relation of these factors to knee valgus and ACL injury risk.
ContributorsDiamond, Alexander (Author) / Harper, Erin (Thesis director) / Ringenbach, Shannon (Committee member) / Wiley, Alex (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2013-05