11 pp. / The US Department of Agriculture (USDA) reported that over two million Americans are using USDA’s SuperTracker (Kevin Concannon, Under Secretary for Food, Nutrition and Consumer Services; March 27, 2013). SuperTracker is an online, interactive tool with which users can create customized healthy dietary and physical activity plans. It can help users analyze their dietary trends and assess whether they are achieving their dietary and physical activity goals. In addition to users’ planning, assessment, and analysis, SuperTracker offers personal goal setting and journaling – recording daily events. This article walks you through the basics of SuperTracker.

More than 60% of the adult population in the United States is overweight, and obesity has reached epidemic proportions in this country. Childhood obesity has more than doubled since 1990, and the health consequences are reflected in the rising cost of health care. There has also been a significant drop in physical activity across the country and physical education is no longer required in middle schools. The lack of physical activity and issues of weight can compromise the ability of the individual who is blind or visually impaired to maneuver through the environment safely and efficiently. The purpose of this study was to examine the perceptions of itinerant teachers of students with visual impairments about the importance of physical activity for their students with visual impairments and its effect on academic success and social relationship.Data was gathered from 175 teachers of students with visual impairments concerning their perceptions regarding the importance of physical activity and obesity and their relationship with academic success and social relationships. The teachers indicated that physical activity for their students is very important. They described a multitude of barriers that account for a lack of involvement in the general physical education classes in which they were enrolled.Teachers reported on their own personal physical activity levels in relationship to the importance they placed on their students' need to be active. The teachers did not indicate that being overweight was a particular issue with their visually impaired students, but they acknowledged that being overweight and a lack of physical activity create additional barriers for academic success and appropriate social relationships.The teachers also reported that the same barriers in physical education classes and access to recreation activities in the community that have been listed in past research studies were still in existence, and these barriers were also part of their dilemma in creating positive physical activity experiences for their students who are visually impaired. This study validated the necessity of further research to find the effective intervention strategies and programs to increase physical activity of students with visual impairments.

The Heart Healthy Kids (H2K) program examines peer mentoring and physical activity of grades 4, 5, and 6 students (n=808 children from 10 schools). This sub-study qualitatively explored the peer mentoring experience, using the social ecological model to examine the experience from multiple perspectives. A qualitative description design was used, with a phenomenological approach to data analysis. Three focus groups were conducted with 17 children (5 male, average age: 10.6 years) at 3 of the H2K intervention schools. Six additional individual interviews were conducted with 1 parents and 1 teacher from each focus group school (all female). Thematic analysis was conducted. Emergent themes included that peer mentors were perceived as “encouragers of physical activity”, “helpers and supporters”, “organizers and administrators”, and “expanders of social networks”. Results suggest that reframing physical activity programs to promote physical activity in the context of fun, unstructured, social engagement, especially those that employ peer mentoring, may be more successful. This research contributes to development of future programs and research, and knowledge of the applicability of peer mentoring in influencing child physical activity levels.

Background: A beneficial effect of physical activity on the risk of cancer at several sites has been consistently observed. Biologic mechanisms that may underlie this relationship are not well understood. A potential mechanism explaining this relationship for some cancer sites is the influence of physical activity on methionine-homocysteine biosynthesis. High levels of total plasma homocysteine concentration (tHcy) indicate a breakdown in this biochemical process. This cycle’s influences on DNA methylation and endogeneous agents involved in oxidative stress are potential mechanisms linking methionine-homocysteine biosynthesis to cancer risk. This research is nested within a larger cross sectional study of healthy volunteers recruited from centers in Ontario and Nova Scotia aimed at understanding modifiable risk factors for cancer. Purpose: This research sought to elucidate the relationship between physical activity and tHcy level. Methods: The target population was healthy male and female subjects aged 20-50. Participants donate a 12ml blood sample after an overnight fast for analysis of tHcy and dietary factors and complete a questionnaire including a physical activity profile for the past month (adapted from the International Physical Activity Questionnaire [IPAQ]) and established predictors of tHcy level such as coffee and alcohol consumption. Multiple linear regression is used to model the relationship between tHcy and physical activity measures while controlling for potential confounders. Results: Analysis on 171 participants has been carried out. Mean tHcy for five quintiles of physical activity (from lowest physical activity score to highest) were found to be 8.40μmol/L (7.76-9.05), 8.60μmol/L (8.00, 9.22), 9.24μmol/L (8.66, 9.81), 8.23 μmol/L(7.64, 8.82), and 8.70μmol/L (8.09, 9.31). Conclusions: The findings of this research do not support a relationship between physical activity and total plasma homocysteine concentration. Results of this study suggest that homocysteine is not a mediating factor for the relationship observed between physical activity and cancer. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2007-09-25 11:19:23.321

Background: Less than half of Canadian youth meet recommended levels of physical activity. This is of concern given the health burden associated with physical inactivity. With the limited success of physical activity interventions, research has begun to focus on how physical and sociocultural environments affect physical activity. Investigation of school and neighbourhood characteristics that facilitate physical activity may identify environmental changes that could increase participation among adolescents. Objectives: The objectives of the two studies comprising the thesis were to examine, among youth in grades 6 through 10: 1) the association between school recreational characteristics and physical activity during free-time and class-time at school, and 2) the effects of perceptions of neighbourhood safety and availability of parks and recreational facilities on physical activity participation outside of school. Methods: Data from the 2006 Canadian Health Behaviour in School-Aged Children Survey (HBSC) were analyzed. Multilevel logistic regression was employed to quantify associations between school and neighbourhood characteristics and physical activity. For the first study, student responses to school-time physical activity scales were dichotomized (≥ 2 vs. <2 hours/week). A cumulative index that considered together policies, varsity and intramural athletics, presence and condition of fields, and condition of gymnasia was constructed based on principals’ reports. In the second study, physical activity outside of school was dichotomized (≥ 4 vs. <4 hours/week). A scale of individuals’ perceptions of safety was constructed. The number of parks and recreational facilities within a 5 km buffer of schools was abstracted from a geographical information system. Results: Objective 1. School recreational features were modestly positively related to adolescents’ physical activity at school, particularly that occurring during free-time. The cumulative effect of school recreational features exerted a stronger effect than any single feature. Objective 2. Perceptions of safety were associated with students’ physical activity, whereas increased availability of parks and recreational facilities neither prevented nor promoted physical activity. Conclusions: Objective 1. High levels of recreational support at schools might promote physical activity among young people. This could inform educational policies and support funding of school recreational opportunities. Objective 2. Improving perceptions of safety might promote physical activity participation among youth. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2008-05-22 15:44:36.541

Current guidelines suggest that physical activity must be performed at a moderate-to-vigorous intensity (MVPA) and accumulated in bouts of at least 10 consecutive minutes to elicit improvement in cardiorespiratory fitness (CRF). In the first study we sought to determine whether the duration and intensity of objectively measured incidental physical activity (IPA; activity performed below the designated threshold) was associated with CRF in abdominally obese, inactive men (n=43) and women (n=92). Secondary analyses examined the associations between light physical activity (LPA), sporadic moderate physical activity (MPA; accumulated in <10 minute bouts), and CRF. Both duration and intensity of IPA were positively associated with CRF among inactive, abdominally obese adults. Sporadic MPA, but not LPA, was an independent predictor of CRF. Whereas some observations suggest that sedentary behaviour (SED) is negatively associated with health outcomes, other evidence fails to support this notion. The primary aim of the second study was to clarify the relationships between SED, LPA, and MVPA with 2-hour glucose and insulin resistance in inactive adults (43 men, 92 women) with abdominal obesity. Secondary analyses examined the association between SED, LPA, MVPA and other common cardiometabolic risk factors. Neither SED nor the physical activity variables were associated with 2-hour glucose or insulin resistance. SED was not associated with any cardiometabolic risk factor; with the exception of blood pressure, LPA was not associated with any cardiometabolic risk factor; and MVPA was independently associated with total cholesterol and triglycerides. Whether IPA is associated with abdominal obesity is unknown. The purpose of study three was to determine the association between IPA and abdominal adipose tissue depots (visceral adipose tissue and subcutaneous adipose tissue) in inactive men (n=42) and women (n=84). Secondary analyses examined the associations between SED, sleep duration, and caloric intake with abdominal obesity. IPA was not associated with any measure of abdominal obesity, nor was LPA. After control for age and sex, MPA was negatively associated with visceral adipose tissue. SED and sleep duration were not associated with abdominal obesity. Caloric intake was not associated with abdominal obesity after control for age and sex. / Thesis (Ph.D, Kinesiology & Health Studies) -- Queen's University, 2011-05-17 13:33:52.518

The purpose of this study was to determine if, after adjusting for the contribution of exercise dose, exercise intensity was associated with the improvement of insulin sensitivity. Abdominally obese, sedentary men (n = 16, [mean±SD] age: 45.0±7.5 yr; waist circumference: 108.6±5.3 cm) and women (n = 18, [mean±SD] age: 42.3±6.2 yr; waist circumference: 100.1±8.2 cm) performed daily, supervised exercise for 3 and 4 months, respectively. Exercising at a self selected exercise intensity, men were required to expend expended 700 kcal per session and women 500 kcal per session. Exercise intensity and dose were determined using heart rate and oxygen consumption data obtained from repeated graded exercise tests. Insulin sensitivity was determined by hyperinsulinemic euglycemic clamp. Insulin sensitivity improved in both men and women (change score: men = 7.2±5.4 mg/kgskm/min, women = 5.8±7.1 mg/kgskm/min) (p < 0.05). Exercise intensity was associated with the improvements in insulin sensitivity in men (unstandardized regression coefficient (β) = 0.43, p = 0.02). Adjusting for exercise dose, the change in abdominal adipose tissue (AT), or the change visceral AT did not alter this association (p < 0.05). Exercise intensity was not associated with the improvement of insulin sensitivity in women (β = - 0.11, p = 0.7). Adjusting for exercise dose, the change in abdominal or visceral AT did not change the association in women (p > 0.05). Our findings suggest that exercise intensity is independently associated with the improvement of insulin sensitivity in abdominally obese men but not women. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2011-06-13 19:56:40.465

Objective The primary objective of this study was two-fold. First, to determine whether incidental physical activity (IPA), which is composed of both light-intensity physical activity (LPA) and sporadic moderate-intensity physical activity (MPA; physical activity accrued in bouts less than 10 minutes), was associated with cardiorespiratory fitness (CRF). Second, to determine whether sporadic MPA was associated with CRF. Methods Participants were abdominally obese (defined as a waist circumference > 102 cm in men and > 88 cm in women), inactive, adult men (N = 24; [mean ± SD] age = 55.5 ± 7.8 years) and women (N = 55; age = 52.3 ± 7.5 years) recruited from Kingston, Canada. Cardiorespiratory fitness was assessed using a graded treadmill test. IPA (activity ≥ 1 metabolic equivalent (MET)) and sporadic MPA (activity ≥ 3 METs accrued in bouts less than 10 minutes) was measured using the SenseWear Pro Armband (SWA). IPA and sporadic MPA were categorized into duration (minutes/day) and expenditure (MET-minutes/day). In secondary analyses, we investigated the association between LPA (activity between 1 – 2.99 METs), sedentary behaviour (SED; activity < 1.0 MET) and CRF. Results Participants accumulated an average of 326.6 ± 127 minutes of IPA per day which was composed of 40.7 ± 17.8 minutes of sporadic MPA and 285.9 ± 118.2 minutes of LPA. Both duration and expenditure of IPA were significantly associated with CRF independent of sex, however, after further control for body mass index and age neither association remained significant (p > 0.05). Sporadic MPA was significantly associated with CRF after control for covariates (p ≤ 0.05). Neither LPA nor SED were associated with CRF after control for covariates (p > 0.05). Conclusions IPA was not significantly associated with CRF, however, sporadic MPA was an independent predictor of CRF. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2011-07-30 16:43:47.703

Parks have a long-standing history of providing leisure and recreation environments to local neighbourhood residents. They are designed to enhance the livability of communities and to provide recreation opportunities for individual health benefits. Recent studies have found that parks are underutilized for physical activity. In order to address this concern, this thesis research included two studies addressing the association between five park characteristics (i.e., park feature and amenity type, condition, cleanliness, neighbourhood type, and a park program) and levels of park usage and physical activity behaviour. Manuscript 1 explores park feature and amenity type, condition, cleanliness, and neighbourhood type in association with park usage and physical activity using the System for Observing Play and Recreation in Communities (SOPARC) and the Environmental Assessment of Public Recreation Spaces (EARPS) observational measurements. Park usage differed between park feature types (p<.001) and neighbourhood types (p<.001), with higher rates of park use and physical activity noted in urban neighbourhoods, and on splash pad, pool, path, and play structure feature types. Physical activity levels were associated with park feature type (p<.001), condition (p<.001) and cleanliness (p<.001) as well as neighbourhood type (p< .05). Manuscript 2 reports on the effectiveness of a family park physical activity program using questionnaire feedback (n=28), and observational comparisons’ of park usage and physical activity when the program was and was not occurring. No significant difference was found for overall park usage and physical activity levels, however the program target area significantly reported more usage (p<.05) when the program was offered. A majority of program participants were currently moderately-vigorously active (79%), met Canadian Physical Activity Guidelines (57%), came to the park with family members (93.1%), walked to the park (85.7%), and visited the park regularly (62%). From these collective findings, this thesis makes an important contribution to furthering our understanding of associations between park characteristics and park usage and physical activity levels. Findings from this study will be useful in guiding park researchers, planners, and designers as well as, park program practitioners and community agencies in promoting and creating more user-friendly and active neighbourhood park environments, as a means to increase population health amongst Canadians. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2011-09-29 10:21:42.042

Physical activity is a powerful modifiable lifestyle factor that reduces the risk of cardiovascular disease (CVD) in adults through favorable changes in conventional risk factors including serum lipids, blood pressure and glycemia. Recent evidence suggests that the cardioprotective effects of physical activity may also be mediated through beneficial effects on vascular function, in particular arterial stiffness. While the beneficial effects of physical activity in CVD risk in adults are irrefutable, data in youth are limited, especially for arterial stiffness. Purpose: The purpose of this project is to explore the continuous association between physical activity and arterial stiffness in youth. Hypothesis: We hypothesized that physical activity is negatively associated with arterial stiffness, whereby highly active youth would display lesser degrees of arterial stiffness than their less active (sedentary) peers. Methods: 485 youth (12-13 yrs) were recruited from the 1995 Manitoba birth cohort involved in the GreatICE asthma and allergy study. Youth were stratified into tertiles (high, medium, low) of self-reported physical activity. Global cardiometabolic risk was determined from a composite score of conventional risk factors including, LDL, SBP, Insulin, Glucose and Triglycerides. Arterial stiffness was assessed non-invasively using conventional pulse wave analysis and velocity. Results: Of the 485 youth who participated in this wave of the study, measures of PWV and PWA were available on 357 and 335 youth respectively. Cardiometabolic risk decreased with increasing levels of vigorous physical activity. Neither measure of arterial stiffness was associated with physical activity. Conclusion: Increased vigorous physical activity is associated with reduced cardiometabolic risk in youth independent of arterial stiffness.