This study determined whether a cadenced-based exercise prescription (CBEP) enabled participants to increase the time they spend doing moderate-to-vigorous intensity physical activity (MVPA) to a greater extent than Standard Care (SC). Forty-six participants were recruited from the ENCOURAGE study and were allocated to SC (n=25) or CBEP (n=21). Data was collected at baseline (T0), prior to the intervention (T1) and then again at 16 (T2) and 24 (T3) weeks. Moderate-to-vigorous physical activity was assessed by accelerometry in 10 minute (MVPA10min) and sporadic bouts (MVPASpor) as well as step counts (StepsTotal, StepsMVPA). Although participants reported that CBEP helped them to increase their motivation to become more active, none of the accelerometer parameters differed between SC and CBEP at baseline, 8, 16, or 24 weeks. These data suggest that CBEP did not have an added benefit for influencing physical activity over time amongst a population of previously sedentary adults.

Regular moderate-vigorous physical activity (MVPA) is associated with significant physiological and psychological health benefits (Department of Health, DoH, 2004). However, many children are not undertaking recommended levels of physical activity (PA) (DoH, 2009). This research examined relationships between physiological health parameters, psychological determinants and PA levels in 10-14 year old schoolchildren (N = 249) and assessed the influence of three school-based PA interventions on these constructs in the context of the Health And Physical activity Promotion in Youth (HAPPY) study. Study 1 revealed that sedentary behaviours, moderate PA (MPA), vigorous PA (VPA) and MVPA levels were higher on weekdays than weekend days (p < .001). However, schoolchildren’s PA is often difficult to measure accurately. The self-report measure utilised in study 2 underestimated total MVPA versus accelerometry for both sexes on weekdays and girls on weekend days (p < .01). However, study 3 highlighted a lack of agreement between two RT3® triaxial accelerometer cut-offs for all activity categories. The importance of VPA for promoting health was highlighted in the updated PA guidelines (DoH, 2011). Study 4 reported that cardiorespiratory fitness (CRF) was positively associated with VPA but not MPA (β = .27, p < .01) and inversely correlated with measures of body composition (% body fat; body mass index; waist circumference) (r = -.74, r = -.60, r = -.39, p < .001). Knowing the health benefits of regular MVPA and VPA, it is important to understand the determinants of PA intentions and behaviours to more effectively promote PA in less active children (studies 5 and 6). An exploratory analysis of the constructs in the Revised Theory of Planned Behaviour and the Modified Social Learning Theory for children predicted PA intentions (R2 = .38, F(5, 171) = 20.19, p < .001; R2 = .13, F(6, 147) = 3.4, p < .01, respectively) but the constructs in either model were unable to predict PA. Recognising the need to promote PA levels, study 7 investigated the effectiveness of three school-based interventions (vs. control) on outcome variables included in studies 1, and 4-6. The Health Education and Psychology Health Promotion conditions produced significant positive change scores between data collection 2 and 3 for CRF (vs. control) whereas the Youth-Led condition produced significant change scores between baseline and data collection 2 for generalised self-efficacy (vs. control). No significant change scores were reported for PA, the RTPB constructs or intentions. In conclusion, this research has emphasised the importance of employing a multidisciplinary approach to aid understanding of schoolchildren’s PA levels. Specific highlights include low weekend day PA as a possible future PA promotion target, although it is vital that accelerometry cut-points are standardised, and the relevance of VPA and body composition in predicting CRF. The psychological models identified some important determinants of PA intentions, but a prominent intention-behaviour gap and a need for more intensive interventions to promote PA levels was apparent.

BACKGROUND: Atherosclerotic cardiovascular (ASCVD) disease is the leading cause of death in the United States. Longstanding poor nutrition habits and lack of exercise contribute to chronic inflammation and promote the development ASCVD. In clinical trials, the Dietary Approaches to Stop Hypertension (DASH) eating pattern, a diet rich in nutrients with anti-inflammatory and antioxidant properties, has been shown to reduce the risk of hypertension. Its role in overall cardiovascular (CV) health, both alone and in combination with an active lifestyle, is less clear. OBJECTIVES: The primary goal of this study is to examine the relationships between the DASH eating pattern, physical activity, the development of incident cardiovascular disease (CVD). Specifically, we will evaluate the independent and combined effects of DASH and moderate to vigorous physical activity (MVPA) on cardiovascular event risk among men and women in the Framingham Heart Study Offspring (FOS) cohort. METHODS: The DASH score was derived from two sets of three-day dietary records gathered during examination visits 3 and 5 in the prospective FOS cohort. Activity was self-reported and used to generate a composite score for MVPA. Scores were constructed for each individual by multiplying the number of hours spent during each day in sedentary, light, moderate, and vigorous activity by a standard weights reflecting the intensity of that activity. Subjects included 2503 individuals (1137 men and 1366 women), aged 30 years and older. Individuals were free of type II diabetes mellitus (T2DM), cancer, and cardiovascular disease at baseline. The DASH score was categorized according to adherence to the eating pattern, first as low, moderate, or high adherence and then dichotomized (DASH score <4.45 vs. ≥4.45). The MVPA score was classified into quintiles and also dichotomized (MVPA score <6.1 vs. ≥6.1). The dichotomous DASH and MVPA scores were then cross-classified and each subject was assigned to one of the following categories: (1) low DASH score / low activity (referent), (2) low DASH / high activity, (3) high DASH / low activity, and (4) high DASH / high activity. Follow-up started at exam 5 and continued through the ninth examination cycle in 2014. Cox proportional-hazard regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for all subjects and for men and women independently, adjusting for confounding by age, BMI, cigarettes smoked per day, and grams per day of alcohol consumed. Factors found not to confound the effects of DASH and MVPA on CV risk were excluded from final models. RESULTS: During a median follow-up of approximately 20 years, 286 and 177 incident CVD cases were documented among men and women, respectively. Women in the highest DASH adherence category had approximately 28% lower total CVD risk than women in the lowest adherence group (HR, 0.72; 95% CI: 0.48-1.10). Effects in men were weaker. Women in the highest quintile of MVPA score had approximately 44% lower risk of CVD than women in the lowest quintile (HR, 0.66; 95% (0.40-1.10). Overall, CVD risk was 26% lower (HR: 0.74 (95% CI: 0.55-0.99) for those in quintile 5 vs. quintile 1. Women in the High DASH/High MVPA category had a 43% lower total CVD risk than women in the Low DASH/Low MVPA group (High DASH/High MVPA: HR, 0.57; 95% (0.36-0.90)). These associations ere generally stronger in women than men. CONCLUSIONS: In this prospective cohort study, active individuals with higher adherence to DASH was associated with a lower atherosclerotic CVD risk compared to those with lower activity and DASH adherence. The beneficial effects of diet in particular were stronger among women than men.

Health literacy (HL) is defined as the degree to which individuals have the capacity to obtain, process, and understand basic health information and services needed to make appropriate health decisions. Low HL has been associated with poorer self-reported health status, inability to manage chronic conditions, and less use of preventive services. More research is needed to explore the relationship between HL and sugar-sweetened beverage (SSB) intake and physical activity (PA). Although numerous HL interventions are evident in the literature, those that test HL as a moderator of effectiveness are lacking. Additionally, it has been recognized that systems-level HL efforts are necessary to lessen the burden of low HL. This dissertation addresses these needs with three unique studies that took place within the rural, medically underserved southwest Virginia region. Study 1 was a secondary analysis that examined the relationship and responsiveness of the Stanford Leisure-Time Activity Categorical Item (L-Cat) and adapted Godin Leisure-Time Exercise Questionnaire (GLTEQ) and determined if baseline HL status moderated intervention effects. There was high agreement L-Cat and adapted GLTEQ for classifying individuals as meeting PA recommendations. Baseline HL status did not moderate change in L-Cat or adapted GLTEQ measures. Study 2 was a secondary analysis that determined if 6-month change in SSB intake predicted 6-month change in body mass index (BMI), weight, and quality of life (QOL), and determined if HL moderated these relationships. The regression models for weight and QOL were not significant. The BMI model was significant. Six-month change in SSB intake, experimental condition, and age were significant predictors for the BMI model. As hypothesized, HL did not moderate relationships in any models. Study 3 details a multilevel mixed-methods needs assessment and collaboratively developed organizational HL improvement plan within the Virginia Department of Health (VDH). Staff responses revealed about half reported doing well across HL domains (written communication, oral communication, self-management and empowerment, supportive systems). However, needs were observed across all domains, with most improvement needed in written communication domain. There were significant correlations between clients' HL status and their perceptions of VDHs' HL practices, indicating potential areas of improvement within VDH. / Ph. D.