Matching Items (7)
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- All Subjects: Obesity
- Creators: Ainsworth, Barbara
- Creators: Gaesser, Glenn A
Description
Cardiovascular disease (CVD) is the number one cause of death in the United States and type 2 diabetes (T2D) and obesity lead to cardiovascular disease. Obese adults are more susceptible to CVD compared to their non-obese counterparts. Exercise training leads to large reductions in the risk of CVD and T2D. Recent evidence suggests high-intensity interval training (HIT) may yield similar or superior benefits in a shorter amount of time compared to traditional continuous exercise training. The purpose of this study was to compare the effects of HIT to continuous (CONT) exercise training for the improvement of endothelial function, glucose control, and visceral adipose tissue. Seventeen obese men (N=9) and women (N=8) were randomized to eight weeks of either HIT (N=9, age=34 years, BMI=37.6 kg/m2) or CONT (N=8, age=34 years, BMI=34.6 kg/m2) exercise 3 days/week for 8 weeks. Endothelial function was assessed via flow-mediated dilation (FMD), glucose control was assessed via continuous glucose monitoring (CGM), and visceral adipose tissue and body composition was measured with an iDXA. Incremental exercise testing was performed at baseline, 4 weeks, and 8 weeks. There were no changes in weight, fat mass, or visceral adipose tissue measured by the iDXA, but there was a significant reduction in body fat that did not differ by group (46±6.3 to 45.4±6.6%, P=0.025). HIT led to a significantly greater improvement in FMD compared to CONT exercise (HIT: 5.1 to 9.0%; CONT: 5.0 to 2.6%, P=0.006). Average 24-hour glucose was not improved over the whole group and there were no group x time interactions for CGM data (HIT: 103.9 to 98.2 mg/dl; CONT: 99.9 to 100.2 mg/dl, P>0.05). When statistical analysis included only the subjects who started with an average glucose at baseline > 100 mg/dl, there was a significant improvement in glucose control overall, but no group x time interaction (107.8 to 94.2 mg/dl, P=0.027). Eight weeks of HIT led to superior improvements in endothelial function and similar improvements in glucose control in obese subjects at risk for T2D and CVD. HIT was shown to have comparable or superior health benefits in this obese sample with a 36% lower total exercise time commitment.
ContributorsSawyer, Brandon J (Author) / Gaesser, Glenn A (Thesis advisor) / Shaibi, Gabriel (Committee member) / Lee, Chong (Committee member) / Swan, Pamela (Committee member) / Buman, Matthew (Committee member) / Arizona State University (Publisher)
Created2013
Description
While obesity rates have plateaued within the last decade,
two-thirds of the United States
population is currently classified as overweight (defined a
s a body mass index [BMI] of
25-29.9 kg/m²) or obese (a BMI greater than 30 kg/m²). Bariatric
surgical interventions
are not only more effective than behavioral treatments
in the short term but are the only
form of obesity intervention with evidence of consisten
t long-term effectiveness.
However, even among bariatric surgery patients, weight
loss often stabilizes and it is
estimated that more than 20% of bariatric surgery patient
s will regain a significant
amount of weight that was initially lost long-term. Li
ttle research to date has been
conducted on physical activity in post bariatric surgery pati
ents. More specifically, there
have been no studies to date examining the effects of Me
ditative Movement (MM)
programs on body composition in bariatric patients. A s
tudy using an 8-week Tai Chi
Easy program was conducted in female gastric bypass patient
s to explore feasibility of
MM in the bariatric population as well as pre- and post-in
tervention changes in weight,
mindfulness, eating behaviors, body awareness, physical a
ctivity patterns, dietary quality
and mood. Data analysis revealed that there were no s
ignificant changes in weight or
physical activity patterns; however, significant changes w
ere observed in anxiety, overall
body awareness and cognitive restraint in eating. Addit
ionally, a significant decrease in
processed meat consumption and a weak trend towards increa
sed consumption of fruits
may suggest an overall improvement in dietary quality.
two-thirds of the United States
population is currently classified as overweight (defined a
s a body mass index [BMI] of
25-29.9 kg/m²) or obese (a BMI greater than 30 kg/m²). Bariatric
surgical interventions
are not only more effective than behavioral treatments
in the short term but are the only
form of obesity intervention with evidence of consisten
t long-term effectiveness.
However, even among bariatric surgery patients, weight
loss often stabilizes and it is
estimated that more than 20% of bariatric surgery patient
s will regain a significant
amount of weight that was initially lost long-term. Li
ttle research to date has been
conducted on physical activity in post bariatric surgery pati
ents. More specifically, there
have been no studies to date examining the effects of Me
ditative Movement (MM)
programs on body composition in bariatric patients. A s
tudy using an 8-week Tai Chi
Easy program was conducted in female gastric bypass patient
s to explore feasibility of
MM in the bariatric population as well as pre- and post-in
tervention changes in weight,
mindfulness, eating behaviors, body awareness, physical a
ctivity patterns, dietary quality
and mood. Data analysis revealed that there were no s
ignificant changes in weight or
physical activity patterns; however, significant changes w
ere observed in anxiety, overall
body awareness and cognitive restraint in eating. Addit
ionally, a significant decrease in
processed meat consumption and a weak trend towards increa
sed consumption of fruits
may suggest an overall improvement in dietary quality.
ContributorsSmith, Lisa L. (Author) / Larkey, Linda K (Thesis advisor) / Ainsworth, Barbara (Committee member) / Chisum, Jack (Committee member) / Ohri-Vachaspati, Punam (Committee member) / McClain, Darya (Committee member) / Arizona State University (Publisher)
Created2014
Description
In adults, consuming a high-fat meal can induce endothelial dysfunction while exercise may mitigate postprandial endothelial dysfunction. Whether exercise is protective against postprandial endothelial dysfunction in obese youth is unknown. The purpose of this study was to determine if high-intensity interval exercise (HIIE) performed the evening prior to a high-fat meal protects against postprandial endothelial dysfunction in obese adolescent males. Fourteen obese adolescent males (BMI%tile=98.5±0.6; 14.3±1.0yrs) completed the study. After initial screening, participants arrived, fasted at 9:00 in the morning where brachial artery flow-mediated dilation (FMD) was measured using duplex ultrasound after 20min of supine rest (7.0±3.0%) and completed a maximal exercise test on a cycle ergometer (VO2peak=2.6±0.5 L/min). Participants were randomized and completed 2 conditions: a morning high-fat meal challenge with evening prior HIIE (EX+M) or a morning high-fat meal challenge without prior exercise (MO). The EX+M condition included a single HIIE session on a cycle ergometer (8 X 2min at ≥90%HRmax, with 2min active recovery between bouts, 42min total) which was performed at 17:00 the evening prior to the meal challenge. In both conditions, a mixed-meal was tailored to participants body weight consisting of 0.7g of fat/kg of body weight consumed (889±95kcal; 65% Fat, 30% CHO). FMD was measured at fasting (>10hrs) and subsequently measured at 2hr and 4hr after high-fat meal consumption. Exercise did not improve fasting FMD (7.5±3.0 vs. 7.4±2.8%, P=0.927; EX+M and MO, respectively). Despite consuming a high-fat meal, FMD was not reduced at 2hr (8.4±3.4 vs. 7.6±3.9%; EX+M and MO, respectively) or 4hr (8.8±3.9 vs. 8.6±4.0%; EX+M and MO, respectively) in either condition and no differences were observed between condition (p(condition*time)=0.928). These observations remained after adjusting for baseline artery diameter and shear rate. We observed that HIIE, the evening prior, had no effect on fasting or postprandial endothelial function when compared with a meal only condition. Future research should examine whether exercise training may be able to improve postprandial endothelial function rather than a single acute bout in obese youth.
ContributorsRyder, Justin Ross (Author) / Shaibi, Gabriel Q (Thesis advisor) / Gaesser, Glenn A (Committee member) / Vega-Lopez, Sonia (Committee member) / Crespo, Noe C (Committee member) / Katsanos, Christos (Committee member) / Arizona State University (Publisher)
Created2014
Description
Cardiovascular disease and diabetes are major health burdens. Diabetes is a primary risk factor of cardiovascular disease, and there is a strong link between obesity and risk of developing diabetes. With the prevalence of prediabetes highest among overweight/obese individuals, investigation into preventative strategies are needed. Aerobic exercise is a potent stimulus for both insulin and non-insulin dependent glucose uptake into the skeletal muscle. A single exercise session can improve insulin sensitivity within hours after exercise. The effects of intensity, type, and volume of exercise on glucose homeostasis have been studied extensively; however, controlling for muscle contraction frequency with a constant exercise intensity and workload has not been examined. The purpose of this study was to compare muscle contraction frequency during aerobic exercise by altering cycling cadence on insulin sensitivity and vascular health. Eleven obese males (age=28yr, BMI=35kg/m2) completed three conditions in random order: 1) control-no exercise; 2) 45-min cycling at 45 revolutions per minute (45RPM) at 65-75%VO2max; 3) 45-min cycling at 90RPM at 65-75%VO2max. Glucose control and insulin sensitivity were assessed with oral glucose tolerance tests (OGTT) 4 hours post-exercise. Vascular health was assessed via flow-mediated dilation (FMD) pre-exercise, 1-hr and 2-hr post exercise and ambulatory blood pressure was assessed pre-exercise, and continually every 15 min post-exercise. Linear mixed models were used to compare the mean differences in outcome variables. There were no significant differences found between control and both exercise conditions for all OGTT outcomes and no differences were found between control and exercise in FMD (all, p>0.05). Significant effects for exercise were found for both brachial and central blood pressure measures. Brachial systolic blood pressures were lower at 2- and 4-hr post-exercise by approximately -10 and -8mmHg, respectively (p<0.001 and p=0.004) versus control. Central systolic blood pressures were lower at 2-, 3-, and 4-hr post-exercise by approximately -8, -9 and -6mmHg, respectively (p<0.001, p=0.021 and p=0.004) versus control. In conclusion, aerobic exercise, regardless of muscle contraction frequency, were unable to effect glucose control and insulin sensitivity. Similarly, there was no effect on vascular function. However, there was a significant effect of aerobic exercise on reducing post-exercise blood pressure.
ContributorsJarrett, Catherine Lee (Author) / Gaesser, Glenn A (Thesis advisor) / Angadi, Siddhartha S (Committee member) / Dickinson, Jared M (Committee member) / Whisner, Corrie M (Committee member) / Todd, Michael W (Committee member) / Arizona State University (Publisher)
Created2017
Description
An increasingly sedentary population in the United States, specifically with adolescents, is putting youth at risk of future health related trauma and disease. This single-case design study, Walking Intervention Through Text Messaging for Adolescents (WalkIT-A), was used to intervene with a 12-year old, physically inactive male, in an attempt to test the efficacy of a 12-week physical activity program that may help reduce health risks by increasing number of steps walked per day. The components of the intervention consisted of a FitBit Zip pedometer, physical activity education, text messages, monetary incentives, and goal setting that adapted personally to the participant. Mean step count increased by 30% from baseline (mean = 3603 [sd = 1983]) to intervention (mean = 4693 [sd = 2112]); then increased slightly by 6.7% from intervention to withdrawal (mean = 5009 [sd = 2152]). Mean "very active minutes" increased by 45% from baseline (mean = 8.8 [sd = 8.9]) to intervention (mean = 12.8 [sd = 9.6]); then increased by 61.7% from intervention to withdrawal (mean = 20.7 [sd = 8.4]). Weight, BMI, and blood pressure all increased modestly from pre to post. Cardiovascular fitness (estimated VO2 max) improved by 12.5% from pre (25.5ml*kg-1*min-1) to post (28.7ml*kg-1*min-1). The intervention appeared to have a delayed and residual effect on the participant's daily steps and very active minutes. Although the idealistic ABA pattern did not occur, and the participant did not meet the target of 11,500 daily steps, a positive trend toward that target behavior in the latter 1/3rd of the intervention was observed. Results suggest the need for an extended intervention over a longer period of time and customized even further to the participant.
ContributorsLamb, Nicholas Reid (Author) / Adams, Marc (Thesis director) / Ainsworth, Barbara (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2014-12
Description
"Globesity," as defined by the World Health Organization, describes obesity as a pandemic affecting at least 400 million people worldwide. The prevalence of obesity is higher among women than men; and in non-Hispanic black and Hispanic populations. Obesity has been significantly associated with increased all-cause mortality, and mortality from cardiovascular disease, obesity-related cancers, diabetes and kidney disease. Current strategies to curb obesity rates often use an ecological approach, suggesting three main factors: biological, behavioral, and environmental. This approach was used to develop four studies of obesity. The first study assessed dietary quality, using the Healthy Eating Index (HEI)-2005, among premenopausal Hispanic and non-Hispanic white women, and found that Hispanic women had lower total HEI-2005 scores, and lower scores for total vegetables, dark green and orange vegetables and legumes, and sodium. Markers of obesity were negatively correlated with total HEI-2005 scores. The second study examined the relationship between reported screen time and markers of obesity among premenopausal women and found that total screen time, TV, and computer use were positively associated with markers of obesity. Waist/height ratio, fat mass index, and leptin concentrations were significantly lower among those who reported the lowest screen time versus the moderate and high screen time categories. The third study examined the relationship between screen time and dietary intake and found no significant differences in absolute dietary intake by screen time category. The fourth study was designed to test a brief face-to-face healthy shopping intervention to determine whether food purchases of participants who received the intervention differed from those in the control group; and whether purchases differed by socioeconomic position. Participants in the intervention group purchased more servings of fruit when compared to the control group. High-income participants purchased more servings of dark green/deep yellow vegetables compared to those in the low-income group. Among those who received the intervention, low-income participants purchased foods of lower energy density, and middle-income participants purchased food of higher fat density. The findings of these studies support policy changes to address increasing access and availability of fruits and vegetables, and support guidelines to limit screen time among adults.
ContributorsMilliron, Brandy-Joe (Author) / Woolf, Kathleen (Thesis advisor) / Vaughan, Linda (Committee member) / Ainsworth, Barbara (Committee member) / Wharton, Chris (Committee member) / Der Ananian, Cheryl (Committee member) / Appelhans, Bradley (Committee member) / Arizona State University (Publisher)
Created2010
Description
Obesity rates among adults have steadily grown in recent decades all the way up to 42.4% in 2018. This is a 12% increase from the turn of the century (Center for Disease Control and Prevention, 2021). A major reason for this rise is increased consumption of processed, high-calorie foods. People eat these foods at a young age and develop bad eating habits that can last for the rest of their lives. It is essential to intervene early and help adolescents form balanced, healthy eating habits before bad habits are already formed. Our solution to this problem is Green Gamers. Green Gamers combines adolescent’s passion for gaming with healthy eating via in-game rewards for healthy eating. People will be able to purchase healthy food items, such as a bag of carrots, and on the packaging there will be a QR code. They will then be able to scan the code on our website, and earn points which will unlock in-game items and other rewards. Video game rewards act as effective motivators for you people to eat more healthy foods. After the solution was formulated, a preliminary survey was conducted to confirm that video game related rewards would inspire children to eat more healthy foods. Based on those results, we are currently in the process of running a secondary market research campaign to learn if gift card rewards are a stronger motivator. Our end goal for Green Gamers would be to partner with large gaming studios and food producers. This would allow us access to many gaming franchises, so that rewards are available from a wide variety of games: making the platform appealing to a diverse audience of gamers. Similarly, a relationship with large food producers would give us the ability to place QR codes on a greater assortment of healthy food items. Although no relationships with large companies have been forged yet, we plan to utilize funding to test our concept on small focus groups in schools.
ContributorsMckearney, John Joseph (Co-author) / Wong, Brendan (Co-author) / Kim, Hwan (Co-author) / Davis, Benjamin (Co-author) / Byrne, Jared (Thesis director) / Hall, Rick (Committee member) / College of Health Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05