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.

All humans desire to have a good quality of life i.e. living in relation to their goals, expectations, standards and concerns in life. The quality of life is related to healthy lifestyle, therefore, practicing health behavior is crucial for children and adolescents as the habits developed in early life persist in later life. However, in the contemporary world it has become quite a challenge to practice health behavior due to exposure to technology, electronic devices and social media which has adversely affected two important components of health behavior i.e. sleep and vigorous physical activity. This study aimed at investigating the impact of sleep duration during school days and vigorous physical activity during the week on quality of life. The data collected from 7700 students aged 11,13 & 15 from Swedish schools within the HSBC study in 2014. ANOVA, linear regression and mean comparison were used to test the hypotheses. The results show that age, gender, long-term disability and physical activity effects sleep duration of children and adolescents. Moreover, children and adolescents who sleep longer hours and do vigorous physical activities have a higher quality of life. Sleep duration have also been found to be associated with a higher quality of life.

All humans desire to have a good quality of life i.e. living in relation to their goals, expectations, standards and concerns in life. The quality of life is related to healthy lifestyle, therefore, practicing health behavior is crucial for children and adolescents as the habits developed in early life persist in later life. However, in the contemporary world it has become quite a challenge to practice health behavior due to exposure to technology, electronic devices and social media which has adversely affected two important components of health behavior i.e. sleep and vigorous physical activity. This study aimed at investigating the impact of sleep duration during school days and vigorous physical activity during the week on quality of life. The data collected from 7700 students aged 11,13 & 15 from Swedish schools within the HSBC study in 2014. ANOVA, linear regression and mean comparison were used to test the hypotheses. The results show that age, gender, long-term disability and physical activity effects the sleep duration of children and adolescents. Moreover, children and adolescents who sleep longer hours and do vigorous physical activities have a higher quality of life. Sleep duration have also been found to be associated with a higher quality of life.

Yes / To assess physical activity outcomes of a pedometer-based physically active learning (PAL) intervention in primary school children. Methods: Six paired schools were randomly allocated to either a 6-week teacher-led pedometer-based physically active learning intervention or a control (n = 154, female = 60%, age = 9.9 [0.3] y). Accelerometers assessed total daily sedentary time, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA). Preintervention mean daily MVPA minutes grouped participants as Low Active (<45 min/d) and High Active (≥45 min/d). Results: From the final sample size, the intervention (n = 52) significantly improved LPA versus control (n = 31, P = .04), by reducing sedentary time. More intervention (+10%) than control (+3%) pupils met the 60 minutes per day guidelines. In both intervention subgroups, pupils spent less time in LPA (P < .05) versus control. The greatest nonsignificant increase was found in the Low Active pupils MVPA levels. Conclusions: Improvements in LPA were statistically significant in the intervention versus control group. In subgroup analysis, Low Active pupils in the intervention showed the greatest beneficial effects and the Most Active pupils may have replaced MVPA and sedentary time with LPA. The intervention group housed clusters of pupils showing variable responsiveness, justifying routine examination of subgroup variability in future studies.

2008 – 2009 metais LAMMC SDI obelų pomologiniame sode atlikti introdukuotų obelų veislių su B. 396 poskiepiu tyrimai, tikslu – ištirti biologines ir ūkines savybes. Tyrimų metu nustatyta vaismedžių žydėjimo tarpsniai (žydėjimo pradžia, masinio žydėjimo pradžia ir pabaiga, žydėjimo pabaiga); vaismedžių augumas (medžio aukštis, vainiko skersmuo, kamieno skersmuo, vainiko projekcijos plotas); vaismedžių derlius, vaisių paskirstymas į klases pagal skersmenį, vaisių skynimo laikas, laikymosi pabaiga, vaisiaus masė, kokybė (išvaizda, patrauklumas, bendra kokybė balais), cheminė sudėtis (tirpios sausosios medžiagos, sausosios medžiagos, titruojamasis rūgštingumas), sulčių išeiga, odelės ir minkštimo tvirtumas. Įvertinus tirtų požymių visumą, nustatyta, kad Lietuvos sąlygomis geriausios kokybės vaisius su B.396 poskiepiu išaugina veislės ‘Aldas’, ‘Vanda’, ‘Rosana’ ir ‘Rubinola’ vaismedžiai. Darbo apimtis: puslapiai 39, lentelės 6, paveikslų 12, naudotos literatūros šaltiniai. / The research was carried out at the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry in 2008–2009. The aim of this study was to evaluate the biological and economical characteristics of the introduced apple cultivars on B.396 rootstock. The following characters of apple trees were established: blooming periods (opening of the first blossoms, beginning/end of the full bloom, the end of blooming), vigour of the trees (height, diameter of a crown, diameter of a trunk, area of a crown projection); apple yield, distribution of fruits to classes according to diameter, harvesting time, storage life, fruit size, quality (appearance, taste, general quality evaluation) and chemical composition (soluble solids, dry matter, titratable acidity), juice output, substance of skin and flesh. ‘Aldas’, ‘Vanda’, ‘Rosana’ and ‘Rubinola’ according biological and economical characteristics is the best among other investigated cultivars on B.396 rootstock in Lithuanian climatic conditions. Work size: pages 39, tables 6, pictures 12, references 44.

Problem: Mostly attributed to lack of time, only about 15% of Canadian adults are currently reaching the Canadian Physical Activity Guidelines (CPAG). Recently, studies have suggested that any bout of aerobic exercise reaching moderate to vigorous intensity has the potential to improve health. Methods: Sixty adults (20 young non-overweight adults, 20 overweight adults, 20 older adults) already doing some resistance training (RT) were recruited. Participants performed eight RT exercises during three visits. The objective was to identify the proportion of time spent at moderate to vigorous intensity during RT sessions. Results: Overall, the participants were at moderate to vigorous intensity during 82% of the time. However, the older adult group compared to the young adult group spent lower proportion of time at moderate to vigorous intensity during RT sessions. Conclusion: Most Canadian adults can reach HR equivalent to those achieved during moderate to vigorous aerobic activity by doing RT.

Obesity is a public health concern and obesity rates increase from adolescence to adulthood. Therefore, the period between 18-24, known as emerging adulthood, may be a crucial period in the development of obesity. Physical activity (PA) is one component of obesity and levels of physical activity decline significantly during emerging adulthood. Additionally, stress is inversely associated with PA, with greater levels of PA associated with lower levels of stress. While most research has focused on whether or how PA may improve stress, much less has focused on how the experience of stress may be related to levels of PA. The limited existing research with a focus on the latter has found that stress negatively impacts PA. However, even less research has examined the associations between stress and vigorous PA (VPA) in emerging adulthood, a crucial period in the development of obesity. Additionally, research as not explored the potential role of perceived stress management ability in the relationship between perceived stress and VPA. Linear regression analyses were run to examine the relationship between perceived stress and days and minutes of past week VPA among first-year college students and to test whether the relationship between perceived stress and VPA was moderated by perceived stress management ability. In unadjusted models, perceived stress was significantly negatively associated with both minutes and days of VPA, indicating that perceived stress may be a barrier to VPA, but in models adjusted for gender and body mass index (BMI), these associations were no longer significant, indicating that there was no association between perceived stress and VPA taking into account gender and BMI. Moderation of the relationship between perceived stress and VPA was not found, indicating that and that the relationship between perceived stress and VPA did not differ by perceived stress management ability in this population. These results are inconsistent with previous research that has found a significant negative relationship between perceived stress and physical activity. Additionally, gender was significantly associated with minutes of VPA. Possible reasons for the inconsistency of these findings and previous research, along with limitations of the current study and future directions are discussed. / text

The purpose of this study was to investigate whether 3 days of dietary nitrate supplementation has positive effects on exercise performance and energy metabolism at rest and during strenuous knee exercise, and exercise recovery. The experimental protocol was a double blind, placebo-controlled, two-period, and within-subjects design. Fourteen healthy nonsmoking males (22.71 ± 0.72yr, 72.93 ± 2.35kg, and 47.67 ± 1.56 ml/kg/min VO2max) participated in the study. Two supplements (nitrate lozenge; NO-L or placebo; PLA) were orally administrated randomly at 48 and 24 hours before each trial day and again 40 minutes before each exercise trial. Total work, peak torque, and respiratory gases were automatically collected during repeated knee extensions/flexions (isokinetic concentric contractions with dominant leg; 4 sets of 28 repetitions at 180°/sec with 30 sec rest intervals) and recovery (6 contractions of 1 repetition maximum with 120 vii sec between contractions). For these results, peak torque, rate of fatigue, work efficiency, and rate of recovery were calculated. Blood specimens were collected at rest before and after the treatment, post exercise, and end of recovery to track the changes in blood glucose and lactate concentrations. There was a significant inverse correlation for total work during knee extension exercise and oxygen consumption (PLA: r = -.560 and NO-L: r = -.546; p < .01, respectively). During the exercise, RER was significantly higher for PLA compared with NO-L (PLA: 1.42 ± 0.02 vs. NO-L: 1.38 ± 0.02: p = .03). Work within each set and total work performed were higher for NO-L, but these differences were not significant. However, NO-L enhanced exercise efficiency by 3.3% when compared with PLA (PLA: 2497.5 ± 134.56 ft-lb/L/min vs. NO-L: 2578.7 ± 132.24 ftlb/L/min; p = .05). Extensor peak torque recovery rate slope was not significant, but meaningfully faster for NO-L (PLA: 2.39 ± 0.52% vs. NO-L: 3.06 ± 0.54%; p = .09) and significant interaction effect (p = .02) was found during recovery contractions, especially from contractions 2 to 3 (p = .03). It is also worth noting that differences in time to peak torque during knee extension exercise for NO-L and PLA approached significances (PLA: 0.213 ± 0.01 sec vs. NO-L: 0.200 ± 0.01 sec; p = .08). The results suggest that 3 days of dietary nitrate supplementation improves rate of exercise recovery and enhances work efficiency during vigorous resistance exercise. / text

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: Physical inactivity has been consistently associated with numerous negative health outcomes that track from childhood into adulthood, making physical activity a special concern in the pediatric population. Dose-response studies are particularly useful when trying to understand the minimal and optimal amounts of physical activity needed to reduce the risk of negative health outcomes. Unfortunately, previous work within youth has relied on self-reported measures of physical activity, and this research does not provide a clear picture of the true relation between physical activity and health. Objectives: Manuscript 1. Describe the dose-response relation between dyslipidemia and moderate-to-vigorous physical activity (MVPA) in youth. Manuscript 2. Quantify the difference between self-reported and objectively measured MVPA in youth. Taken together, the overall objective of this thesis was to examine the dose-response relation between objectively measured MVPA and dyslipidemia in youth and determine how this may affect current Canadian physical activity guidelines. Methods: Both manuscripts used data from the U.S. National Health and Nutrition Examination Survey. Fractional polynomial regression modeling was used to fit the dose-response curves between MVPA and lipid/lipoprotein measurements. Regression analysis as well as a Bland-Altman plot was used to explain the discrepancy between self-reported and objective measures of MVPA. All analyses were completed using SAS statistical software. Results: Manuscript 1. Risks for high-risk HDL-cholesterol and triglyceride values decreased in a curvilinear manner with increasing minutes of MVPA. The greatest reduction in risk occurred within the first 30 min/d of MVPA. The relation between level of MVPA and LDL-cholesterol was unclear. Manuscript 2. The average youth over-reported their MVPA by ~30 min/d. The over-reporting was not mediated by basic demographic factors; however, the difference in reporting was systematic in nature such that inactive youth over-reported to the greatest extent. Conclusions: Manuscript 1. Youth need to accumulate 30 min/d of MVPA to greatly reduce their risk for dyslipidemia. Manuscript 2. Youth tend to over-report their daily MVPA by approximately 30 min/d. Combined, the results from this thesis suggest that physical activity recommendations for cardiovascular health in youth should suggest a minimum of 30 min/d of MVPA and preferred level of 60 min/d. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2009-09-07 08:48:03.896