Linn Goldberg

The PHLAME (Promoting Healthy Lifestyles: Alternative Models' Effects) firefighter study: outcomes of two models of behavior change.

Objective: PHLAME’s (Promoting Healthy Lifestyles: Alternative Models’ Effects) objective was to assess and compare two means to promote healthy lifestyles. Methods: Prospective trial among 599 firefighters randomized by station to 1) team-centered curriculum, 2) one-on-one motivational interviewing (MI), and 3) controls. Assessment included dietary behavior, physical activity, weight, and general well-being at baseline and 12 months. Program effects were determined using an analysis of covariance (ANCOVA) based approach, and models for relationships were evaluated with path analysis. Results: Both interventions were acceptable and delivered with high fidelity. The team and MI programs increased fruit and vegetable consumption (P < 0.01 and 0.05, respectively) and general well-being (P < 0.01). Significantly less weight gain occurred in both (P < 0.05). A cross-sectional model was consistent with mediation differing between interventions. Conclusions: Both a team-centered and individual-oriented intervention promoted healthy behaviors. The scripted team curriculum is innovative, exportable, and may enlist influences not accessed with individual formats.

Mediating mechanisms in a program to reduce intentions to use anabolic steroids and improve exercise self-efficacy and dietary behavior.

This study investigated the mediating mechanisms responsible for the effects of a program designed to reduce intentions to use anabolic steroids, improve nutrition, and increase strength training self-efficacy. Fifteen of 31 high school football teams (N = 1,506 players at baseline) in Oregon and Washington were assigned to receive the intervention. The multicomponent program addressed the social influences promoting ergogenic drug use and engaging students in healthy nutrition and strength training alternative behaviors. Although the results differed across the three dependent variables, the program appeared to work by changing team norms. Unlike prevention of other drugs, changes in knowledge and perceived severity were mediators of program effects in this study.

Drug testing athletes to prevent substance abuse: background and pilot study results of the SATURN (Student Athlete Testing Using Random Notification) study.

PURPOSE To assess the deterrent effect of mandatory, random drug testing among high school (HS) athletes in a controlled setting. METHODS Two high schools, one with mandatory drug testing (DT) consent before sports participation, and a control school (C), without DT, were assessed during the 1999-2000 school year. Athletes (A) and nonathletes (NA) in each school completed confidential (A) or anonymous (NA) questionnaires developed for this study, respectively, at the beginning and end of the school year. Positive alcohol or drug tests required parent notification and mandatory counseling without team or school suspension. Thirty percent of the DT athletes were tested. Data were analyzed using the end of the school year measure, adjusted for the initial questionnaire results. Demographics of the athlete sample revealed that mean age was 15.5 years with 81.5% white, 9.6% Hispanic, 4.5% Asian, 2.6% American Indian/Native Alaskan, 1.3% African-American, and 1.3% Native Hawaiian/Pacific Islander. RESULTS A (n = 276) and NA (n = 507) were assessed at the beginning (baseline) and at the end of the school year (A, n = 159; NA, n = 338). The past 30-day index of illicit drugs (4-fold difference) and athletic enhancing substances (3-fold difference) were lower (p < .05) among DT athletes at follow-up without difference in alcohol use. However, most drug use risk factors, including norms of use, belief in lower risk of drugs, and poorer attitudes toward the school, increased among DT athletes (p < .05). Although a reduction in the illicit drug use index was present among nonathletes at the DT school, at the end of the school year, it did not achieve statistical significance (p < .10). CONCLUSIONS Random DT may have reduced substance use among athletes. However, worsening of risk factors and small sample size suggests caution to this drug prevention approach. A larger long-term study to confirm these findings is necessary.

The effect of exercise on lipid metabolism in men and women

SummaryLipoprotein abnormalities constitute a major risk for development of cardiovascular disease. These substances, which are comprised of various lipids and proteins (apoproteins), are influenced by specific enzymes which eject their concentrations. It has been demonstrated that elevated total cholesterol and LDL cholesterol are directly associated with the development of coronary artery disease, whereas HDL cholesterol has an inverse relationship with coronary heart disease (CHD). Although more controversial, triglycerides may also be directly associated with coronary atherosclerosis. Favourable changes in lipid levels have been shown to reduce coronary mortality. Exercise may constitute a non-pharmacological approach to lipoprotein therapy.Many exogenous factors also influence lipoprotein concentrations. Changes in diet, body composition, age, as well as medication and akohol usage may directly alter lipid levels. In addition, they can be artificially affected by the analytical method.The immediate effects of one to several bouts of physical activity appear to influence lipoprotein level A reduction in triglycerides has been shown afler physical exertion, especially among trained individuals and those with hypertriglyceridaemia. These acute changes may reflect the utilisation of both muscle and plasma triglycerides as fuels during exertion. After more prolonged training, changes in lipoproteins may also occur. However, since exercise is accompanied by many co-variables which also favourably alter these levels (e.g. lower percentage of body fat, dietary alterations), it is difficult to determine the direct effect of regular physical activity. Initial studies of exercise training’s ejects on total cholesterol did not differentiate changes in HDL and LDL cholesterol. Subsequent research has observed these specific cholesterol fractions. Consistant reduction in LDL cholesterol levels have not been convincingly demonstrated. Although HDL cholesterol has been shown to increase in certain studies, the response has been variable in other investigations. These latter responses may have been due to the fact that HDL cholesterol changes may be dependent on levels prior to conditioning. Assessment of HDL cholesterol subfractions (HDLL2 and HDL3), which could additionally impact on cardiovascular risk reduction, have shown favourable increases in HDL2, but as yet these HDL moieties have not been adequately investigated. Reductions in triglyceride levels ajier training among those with elevated values and benecial apoprotein changes post-training have been reported, although few studies exist.Recent research suggests that improved lipid profiles after exercise may be due to alterations in lipoprotein enzyme activity. This area will be important in the future and offers promise for explaining the relationship of exercise and lipoprotein change, as well as the variability of response observed among individuals.Although most studies have considered aerobic training, other forms of exercise such as resistive or strength training, may also evoke favourable lipoprotein changes. Additionally, a preponderance of exercise and lipid research have concerned men. Women have generally shown a lowering of lipoprotein risk factor levels after training. Previously reported contrary data probably reflects women’s pre-exercise low risk lipid profiles.A reduction in coronary mortality has been associated with an active lifestyle. Likewise, an association between exercise and beneficial lipoprotein levels exists. Further prospective randomised studies of individuals with lipoprotein abnormalities, controlled for confounding variables, are necessary before the ejects of physical exertion and lipid metabolism are more clearly understood.

Metabolic myopathies: Evaluation by graded exercise testing

Exertional muscle pain and fatigue are common complaints; some patients with these symptoms have a metabolic myopathy. We have performed graded exercise testing with analysis of expired ventilation on 13 individuals with various kinds of metabolic myopathies. Their results differed from normal and reflected the underlying biochemical abnormality. Patients with disorders of the mitochondrial electron transport chain demonstrated marked limitations in aerobic metabolism and a greatly reduced maximum oxygen consumption. During intense exertion, normal individuals increase carbon dioxide generation due to buffering of lactic acid. This did not occur in patients with McArdle disease, in whom the respiratory exchange ratio (carbon dioxide production/oxygen consumption) did not rise above 1.0 at maximum exercise. These results indicated a deficit in anaerobic metabolism. Pyruvate dehydrogenase complex allows pyruvate produced from carbohydrate metabolism to enter the citric acid cycle. Patients with this enzyme deficiency showed an initially normal pattern followed by an abrupt cessation in carbohydrate dependent aerobic metabolism at higher work loads. During high-intensity exercise, progressive anaerobic metabolism was not accompanied by additional oxygen consumption. Finally, results from a patient with carnitine palmitoyl transferase deficiency revealed an early dependence on carbohydrate metabolism. The ventilatory threshold occurred at a low percentage of maximal oxygen consumption, reflecting the limited availability of lipid substrates for aerobic metabolism. Detection of some muscle metabolic abnormalities can be made on small biopsy specimens. However, definitive diagnosis of the defect nearly always requires studies on fresh or frozen muscle tissue obtained by an open biopsy. The decision on how the tissue should be processed and which metabolic studies should be performed frequently needs to be made before the biopsy is obtained. Thus, a noninvasive method to initially characterize patients with potential metabolic disorders is useful. Exercise testing with expired gas analysis can indicate the presence of a metabolic myopathy and results can then be used to direct the appropriate biochemical evaluations.

Rationale, design and methods of the HEALTHY study behavior intervention component

HEALTHY was a multi-center primary prevention trial designed to reduce risk factors for type 2 diabetes in adolescents. Seven centers each recruited six middle schools that were randomized to either intervention or control. The HEALTHY intervention integrated multiple components in nutrition, physical education, behavior change and communications and promotion. The conceptual rationale as well as the design and development of the behavior intervention component are described. Pilot study data informed the development of the behavior intervention component. Principles of social learning and health-related behavior change were incorporated. One element of the behavior intervention component was a sequence of peer-led, teacher-facilitated learning activities known as FLASH (Fun Learning Activities for Student Health). Five FLASH modules were implemented over five semesters of the HEALTHY study, with the first module delivered in the second semester of the sixth grade and the last module in the second semester of the eighth grade. Each module contained sessions that were designed to be delivered on a weekly basis to foster self-awareness, knowledge, decision-making skills and peer involvement for health behavior change. FLASH behavioral practice incorporated individual and group self-monitoring challenges for eating and activity. Another element of the behavior intervention component was the family outreach strategy for extending changes in physical activity and healthy eating beyond the school day and for supporting the students lifestyle change choices. Family outreach strategies included the delivery of newsletters and supplemental packages with materials to promote healthy behavior in the home environment during school summer and winter holiday breaks. In conclusion, the HEALTHY behavior intervention component, when integrated with total school food and physical education environmental changes enhanced by communications and promotional campaigns, is a feasible and acceptable mechanism for delivering age-appropriate social learning for healthy eating and physical activity among an ethnically diverse group of middle school students across the United States.

Exercise Conditioning and Intraocular Pressure

We studied the intraocular pressure response to short-term maximal aerobic exertion before and after exercise conditioning in ten healthy sedentary volunteers. Before exercise conditioning, mean intraocular pressure +/- S.E.M. decreased by 5.9 +/- 0.6 mm Hg after short-term maximal aerobic exercise, returning to baseline in a mean of 37 +/- 4 minutes. After four months of exercise conditioning, this ocular hypotensive response was significantly dampened, with a mean intraocular pressure reduction of only 1.6 +/- 0.4 mm Hg after short-term maximal aerobic exercise (P less than .01). Additionally, a significant reduction in baseline intraocular pressure occurred, with a mean intraocular pressure of 14.3 +/- 0.7 mm Hg before exercise conditioning, declining to a mean intraocular pressure of 13 +/- 0.9 mm Hg (P less than .02) after four months of physical training. Exercise conditioning may significantly reduce baseline intraocular pressure and attenuate the hypotensive response to short-term maximal aerobic exercise.

Long-term effects of a worksite health promotion program for firefighters.

OBJECTIVE To describe effects of 2 worksite health promotion programs for firefighters, both immediate outcomes and the long-term consequences for 4 years following the interventions. METHODS At baseline, 599 firefighters were assessed, randomized by fire station to control and 2 different intervention conditions, and reevaluated with 6 annual follow-up measurements. RESULTS Both a team-centered peer-taught curriculum and an individual motivational interviewing intervention demonstrated positive effects on BMI, with team effects on nutrition behavior and physical activity at one year. Most differences between intervention and control groups dissipated at later annual assessments. However, the trajectory of behaviors across time generally was positive for all groups, consistent with lasting effects and diffusion of program benefits across experimental groups within the worksites. CONCLUSIONS Although one-year programmatic effects did not remain over time, the long-term pattern of behaviors suggested these worksites as a whole were healthier more than 3 years following the interventions.

Risk factors for type 2 diabetes in a sixth- grade multiracial cohort: the HEALTHY study

OBJECTIVE HEALTHY is a 3-year middle school intervention program designed to reduce risk factors for type 2 diabetes. The prevalence of diabetes risk factors at baseline in a cohort of 6,358 sixth-grade students is reported. RESEARCH DESIGN AND METHODS Forty-two schools at seven U.S. sites were randomly assigned to intervention or control. Students participated in baseline data collection during fall of 2006. RESULTS Overall, 49.3% of children had BMI ≥85th percentile, 16.0% had fasting blood glucose ≥100 mg/dl (<1% had fasting blood glucose ≥126 mg/dl), and 6.8% had fasting insulin ≥30 μU/ml. Hispanic youth were more likely to have BMI, glucose, and insulin levels above these thresholds than blacks and whites. CONCLUSIONS Sixth-grade students in schools with large minority populations have high levels of risk factors for type 2 diabetes. The HEALTHY intervention was designed to modify these risk factors to reduce diabetes incidence.

Shifts in BMI Category and Associated Cardiometabolic Risk: Prospective Results From HEALTHY Study

OBJECTIVES: To evaluate shifts across BMI categories and associated changes in cardiometabolic risk factors over 2.5 years in an ethnically diverse middle school sample. METHODS: As part of HEALTHY, a multisite school-based study designed to mitigate risk for type 2 diabetes, 3993 children participated in health screenings at the start of sixth and end of eighth grades. Assessments included anthropometric measures, blood pressure, and glucose, insulin, and lipids. Students were classified as underweight, healthy weight, overweight, obese, or severely obese. Mixed models controlling for school intervention status and covariates were used to evaluate shifts in BMI category over time and the relation between these shifts and changes in risk factors. RESULTS: At baseline, students averaged 11.3 (±0.6) years; 47.6% were boys, 59.6% were Hispanic, and 49.8% were overweight or obese. Shifts in BMI category over time were common. For example, 35.7% of youth who were overweight moved to the healthy weight range, but 13% in the healthy weight range became overweight. BMI shifts were not associated with school intervention condition, household education, or youth gender, race/ethnicity, pubertal status, or changes in height. Increases in BMI category were associated with worsening of cardiometabolic risk factors, and decreases were associated with improvements. Boys who increased BMI category were more vulnerable to negative risk factor changes than girls. CONCLUSIONS: There are substantial shifts across BMI categories during middle school that are associated with clinically meaningful changes in cardiometabolic risk factors. Programs to promote decreases in BMI and prevent increases are clearly warranted.