Joseph J. Carlson

Self-efficacy, psychosocial factors, and exercise behavior in traditional versus modified cardiac rehabilitation.

BACKGROUND Self-efficacy and social support are established determinants of exercise adherence and have potential usefulness for tailoring independent exercise regimens for cardiac patients. Highly supervised traditional cardiac rehabilitation programs may be a barrier for independent exercise self-efficacy in low - and moderate-risk patients. PURPOSE The authors evaluated changes in psychosocial measures including self-efficacy and social support in 80 cardiac patients with low to moderate risk randomized to a traditional cardiac rehabilitation protocol (TP) or modified protocol (MP). These measures also were assessed for their potential to predict subsequent exercise behavior. METHODS The TP (n = 38) emphasized a supervised exercise regimen and included continuous electrocardiogram (ECG) monitoring for 3 months. The lower cost MP (n = 42) emphasized independent exercise and included group education/support meetings, and gradually weaned patients from continuous ECG monitoring and direct medical supervision. RESULTS Repeated measures analyses of variance indicated that MP patients had higher levels of self-efficacy for independent exercise without continuous ECG monitoring (P < .05). No other protocol differences were found. Multiple regression analyses using the pooled sample (excluding dropouts) indicated that self-efficacy for independent exercise was the only significant predictor of exercise over 6 months (R2=.28 [adjusted R2= .221 P < .01). In contrast to previous reports, social support for exercise was not a significant predictor of exercise behavior. CONCLUSIONS These findings suggest cardiac rehabilitation programs for low- and moderate-risk patients should emphasize educational and patient monitoring methods that promote patient self-efficacy for independent exercise. Programs that emphasize highly supervised exercise including longer term use of continuous ECG monitoring may impair self-efficacy for independent exercise. Longer-term studies are needed to fully determine the value of using psychosocial measures for designing individualized exercise programs and predicting long-term exercise behavior in cardiac patients.

Determining the Efficacy of a Resiliency Training Approach in Adults With Type 2 Diabetes

PURPOSE The purpose of this randomized clinical study was to test the efficacy of a resiliency training approach for people with diabetes who have previously received standard diabetes self-education. METHODS A single-blinded, randomized design was employed with repeated measures (baseline, 3 months, 6 months) with 67 participants assigned to either treatment as usual (n = 37) or the resiliency classes (n = 30). Outcome variables included physiological measures (glycosylated hemoglobin, waist measurement, eating and exercise habits) and psychosocial measures (self-efficacy, locus of control, social support, and purpose in life). RESULTS Analyses of variance indicated that the intervention group had higher levels of resiliency as reported by knowing positive ways of coping with diabetes-related stress, knowing enough about themselves to make right diabetes choices, having fun in life, eating healthier, and increasing physical activity compared with the control group at 3 months (P < .05). Glycosylated hemoglobin and waist measurement improved but not significantly. CONCLUSIONS Interventions to foster resilience among people with diabetes have the potential to make an important contribution to increasing positive life outcomes. Diabetes educators using the resiliency approach in tandem with standard diabetes education programs can assist their patients to become more self-directed in their diabetes care.

Dietary Fiber and Nutrient Density Are Inversely Associated with the Metabolic Syndrome in US Adolescents

BACKGROUND There is no consensus as to whether low dietary intakes of saturated fat or cholesterol, or high intakes of dietary fiber are related to a lower prevalence of metabolic syndrome (MetS) in adolescent children. OBJECTIVE To determine whether a fiber-rich diet as measured by a fiber index (grams fiber/1,000 kcal) is associated with lower rates of MetS among adolescents vs a diet low in saturated fat or cholesterol as measured by a saturated fat index (grams saturated fat/1,000 kcal) and a cholesterol index (milligrams cholesterol/1,000 kcal), respectively. DESIGN/PARTICIPANTS/SETTING Cross-sectional analysis of 12- to 19-year-old boys and girls (N=2,128) who participated in the National Health and Nutrition Examination Survey 1999-2002. OUTCOMES AND STATISTICAL ANALYSES: The prevalence of MetS (abnormal values of three or more of the following: waist circumference, blood pressure, fasting serum high-density lipoprotein cholesterol, triglycerides, and glucose) was compared across quintiles of the dietary indexes (fiber index, saturated fat index, and cholesterol index) derived from 24-hour recalls. χ(2) tests determined the prevalence across dietary quintiles, and multivariate logistic regression evaluated the association of the dietary indexes with MetS. Weighted analyses were used controlling for sex, age, ethnicity, and family income. Significance was set at P≤0.05. RESULTS The overall prevalence of MetS was 6.4% (n=138). There was a graded inverse association between the fiber index and MetS (P<0.001) with a threefold difference between the lowest and highest quintiles (9.2% vs 3.1%). Each quintile increase in the fiber index was associated with a ∼20% decrease in MetS (adjusted odds ratio 0.83, 95% confidence interval 0.68-1.00; P≤0.043). Neither the saturated fat index (P=0.87) nor the cholesterol index (P=0.22) was significantly associated with MetS. CONCLUSIONS Higher intakes of dietary fiber, but not low intakes of saturated fat or cholesterol are related to the MetS in adolescents. These findings suggest that to reduce the risks for MetS in adolescents, it is more important to emphasize a paradigm that promotes the inclusion of fiber-rich, nutrient-dense, plant-based foods vs what foods to restrict or exclude as is commonly done when the focus is on total fat, cholesterol, or saturated fat intake.

Pre- and post- prandial appetite hormone levels in normal weight and severely obese women.

BackgroundAppetite is affected by many factors including the hormones leptin, ghrelin and adiponectin. Ghrelin stimulates hunger, leptin promotes satiety, and adiponectin affects insulin response. This study was designed to test whether the pre- and postprandial response of key appetite hormones differs in normal weight (NW) and severely obese (SO) women.MethodsTwenty three women ages 25–50 were recruited for this study including 10 NW (BMI = 23.1 ± 1.3 kg/m2) and 13 SO (BMI = 44.5 ± 7.1 kg/m2). The study was conducted in a hospital-based clinical research centre. Following a 12-hour fast, participants had a baseline blood draw, consumed a moderately high carbohydrate meal (60% carbohydrate, 20% protein, 20% fat) based on body weight. Postprandially, participants had six blood samples drawn at 0, 15, 30, 60, 90, and 120 minutes. Primary measures included pre- and post-prandial total ghrelin, leptin, adiponectin and insulin. A repeated measures general linear model was used to evaluate the hormone changes by group and time (significance p ≤ 0.05).ResultsThere were significant differences between the NW and the SO for all hormones in the preprandial fasting state. The postprandial responses between the SO versus NW revealed: higher leptin (p < 0.0001), lower adiponectin (p = 0.04), trend for lower ghrelin (p = 0.06) and insulin was not different (p = 0.26). Postprandial responses over time between the SO versus NW: higher leptin (p < 0.001), lower ghrelin and adiponectin (p = 0.004, p = 0.015, respectively), and trend for higher insulin (p = 0.06).ConclusionThis study indicates that significant differences in both pre- and selected post- prandial levels of leptin, ghrelin, adiponectin and insulin exist between NW and SO women. Improving our understanding of the biochemical mechanisms accounting for these differences in appetite hormones among individuals with varying body size and adiposity should aid in the development of future therapies to prevent and treat obesity.

A Pilot Study to Determine the Feasibility of the Low Glycemic Index Diet as a Treatment for Overweight Children in Primary Care Practice

BACKGROUND The prevalence of overweight children is increasing. Experimental evidence and specialty clinic trials suggest that a low glycemic index (LGI) diet could be an effective primary care-based treatment for overweight children. OBJECTIVE Conduct a pilot study to determine whether parents of overweight children can lower the glycemic index (GI) of their childs diet after receiving brief instructions and a handout from their pediatrician; and the diets impact on body mass index (BMI). PATIENTS Children 5-12 years with BMIs greater than the 95th percentile. INTERVENTION Brief description of the LGI diet and a handout categorizing foods based on their GI and sample meals. DESIGN Nonrandomized, 12-week pilot study. MEASURES BMI, 24-hour recall, and food frequency questionnaire (FFQ) at entry; 3-day food records at 3, 6, and 9 weeks; BMI, FFQ, and questionnaire at 12 weeks. A GI score derived from standard GI tables. RESULTS Of 34 children initially enrolled, 15 completed the study. Of these, 14 lowered their GI score (mean initial score = 26.6; mean score at 12 weeks 15.6; P <.0001). Mean daily carbohydrate (CHO) intake decreased by 73 g over the study period (P <.02), and mean daily caloric intake decreased by 292 kcal (P <.02). All 15 parents described the diet as easy to understand; 10 reported that their child was generally able to follow the diet. BMI Z-score decreased in 12 of 15 children. CONCLUSION This pilot study suggests that implementing the LGI diet is feasible in primary care for some patients. Further study is warranted with larger study and comparison groups.

A program model to enhance adherence in work-site-based fitness programs.

We describe a program model designed to achieve high adherence, a major problem for work-site exercise/fitness programs. Our model is a 6-month program consisting of 15 1-hour program meetings, with participants exercising on their own time four times per week. Procedures employed to enhance adherence are contracting, group competition, monitoring, and social support. This program model has been applied nine times. One hundred fifty-nine university employees took part in the initial test with a dropout rate of 9% (15 persons). The average adherence rate for nondropouts was 98%, which is higher than rates usually reported in the literature. Adherence was defined as exercising four times a week.

Association between the family nutrition and physical activity screening tool and cardiovascular disease risk factors in 10-year old children

OBJECTIVE To examine the association of the Family Nutrition and Physical Activity (FNPA) screening tool with cardiovascular disease (CVD) risk factors in 10-year old children. METHODS A total of 119 children were assessed for body mass index (BMI), percent body fat, waist circumference, total cholesterol, high-density lipoprotein-cholesterol (HDL), and resting blood pressure. A continuous CVD risk score was created using total cholesterol to HDL-cholesterol ratio (TC:HDL), mean arterial pressure (MAP), and waist circumference. The FNPA survey was completed by parents. RESULTS The FNPA score was significantly correlated with adiposity measures (r = ?0.35 to ?0.43) and the continuous CVD risk score (r = ?0.22) (p < 0.05) but not with TC:HDL or MAP. The prevalence of overweight and obese (43.1% vs. 14.9%) and the mean values for BMI (20.3 ? 4.3 vs. 18.0 ? 2.7 kg/m(2)) and percent body fat (24.8 ? 8.3% vs. 20.1 ? 5.7%) were significantly higher in children with a FNPA score ? 25 when compared to those with a FNPA score > 25 (median split) (p < 0.05). The continuous CVD risk score was not significantly different between these two groups. Overweight and obese children had a significantly lower mean FNPA score when compared to normal weight children. CONCLUSION Children from a high-risk, obesogenic family environment (determined using the FNPA) have a higher level of adiposity and CVD risk factor profile than children from a low-risk family environment. The FNPA screening tool can help identify children that may be at risk for overweight and adverse CVD risk factor development.

Differences in energy expenditure between high- and low-volume training

Abstract Several studies have examined energy expenditure in various sports but there is a lack of research on the contribution of exercise and habitual activity during different training periods. This study examined changes in total daily energy expenditure (TDEE) and its components during high- and low-volume training periods. Further, changes in time spent in sedentary, light, moderate and vigorous activity in response to different training volumes were explored. Energy expenditure was measured in 15 male endurance athletes during 2 non-consecutive weeks – 1 week of high volume (>13 hours) training and another week of low volume (<7 hours) training. The SenseWear Pro 3 Armband, individual heart-rate-oxygen consumption regression and indirect calorimetry was used to measure non-exercise activity thermogensis (NEAT), exercise energy expenditure (EEE) and resting metabolic rate, respectively. Time spent at different intensities was assessed using previously established MET cutpoints. TDEE as well as EEE increased significantly with higher training volume, while no difference in NEAT occurred. Further, significantly less time was spent in sedentary activities during the high-volume week. These results suggest that highly trained athletes do not compensate for increased training volume and reduce sedentary activities to allow for more training time.

Junk food consumption and screen time: association with childhood adiposity.

OBJECTIVES To determine the joint association of junk food consumption (JFC) and screen time (ST) with adiposity in children. METHODS Two hundred fourteen (121 girls, 93 boys) third-to-fifth-grade students (54% Hispanic, 35% African American, 8% white) completed a lifestyle behavior survey, which included self-reported JFC and ST, as part of a school-based lifestyle intervention program. RESULTS Neither JFC nor ST, independently or jointly, was associated with adiposity measures. JFC and ST were significantly correlated (r = .375). CONCLUSIONS The low achievement of physical activity and screen time recommendations and high prevalence of overweight/obesity in this mostly minority, low socioeconomic status population indicates a potential focus for intervention.

Association of the Family Nutrition and Physical Activity Screening Tool with Weight Status, Percent Body Fat, and Acanthosis Nigricans in Children from a Low Socioeconomic, Urban Community

OBJECTIVE OBJECTIVE To examine the association of the Family Nutrition and Physical Activity (FNPA) screening tool with weight status, percent body fat, and acanthosis nigricans (AN) in 6- to 13-year-old children from a low socioeconomic, urban community. METHODS Children (n=415) from four elementary schools located around Flint, Michigan were assessed for body mass index, percent body fat, and AN. The FNPA screening tool was completed by parents. Mann-Whitney U tests were used to assess differences in FNPA score by sex and presence of AN. Logistic regression was used to evaluate the association of the FNPA (tertiles) with weight status and AN. RESULTS Children with AN (13.7%) had a significantly lower FNPA score (56.3 + 7.1) compared with children without AN (61.0 + 7.1; P<.05). Children with FNPA scores in the lowest tertile (high-risk) had odds ratios of 1.74 (95% CI =1.05 - 2.91) and 2.77 (95% CI =1.22 - 6.27) compared with children with FNPA scores in the highest tertile (low-risk) for being overfat and having AN, respectively. CONCLUSION Although the FNPA screening tool did not predict risk for being overweight or obese, it was significantly associated with an increased odds of children at risk for being overfat or having AN.