Physical activity from adolescence to young adulthood : patterns of change, and their associations with activity domains and sedentary time

BackgroundLongitudinal studies demonstrate an average decline in physical activity (PA) from adolescence to young adulthood. However, while some subgroups of adolescents decrease activity, others increase or maintain high or low activity. Activity domains may differ between subgroups (exhibiting different PA patterns), and they offer valuable information for targeted health promotion. Hence, the aim of this study was to identify PA patterns from adolescence to young adulthood; also to explore the associations of (i) changes in PA domains and in sedentary time, (ii) sociodemographic factors, and (iii) self-rated health with diverging PA patterns.MethodsThe observational cohort study data encompassed 254 adolescents at age 15 and age 19. K-means cluster analysis for longitudinal data was performed to identify participant clusters (patterns) based on their accelerometry-measured moderate-to-vigorous PA (MVPA). Logistic regressions were applied in further analysis.ResultsFive PA patterns were identified: inactivity maintainers (n=71), activity maintainers (n=70), decreasers from moderate (to low) PA (n=61), decreasers from high (to moderate) PA (n=32), and increasers (n=20).At age 15, participation in sports clubs (SC, 41-97%) and active commuting (AC, 47-75%) was common in all the patterns. By age 19, clear dropout from these activities was prevalent (SC participation mean 32%, AC 31-63%). Inactivity maintainers reported the lowest amount of weekly school physical education.Dropout from SC - in contrast to non-participation in SC - was associated with higher odds of being a decreaser from high PA, and with lower odds of being an inactivity maintainer. Maintained SC participation was associated with higher odds of belonging to the decreasers from high PA, and to the combined group of activity maintainers and increasers; also with lower odds of being an inactivity maintainer. Maintenance/adoption of AC was associated with decreased odds of being an inactivity maintainer. Self-reported health at age 19 was associated with the patterns of maintained activity and inactivity.ConclusionsPA patterns diverge over the transition to adulthood. Changes in SC participation and AC show different associations with diverging PA patterns. Hence, tailored PA promotion is recommended.Peer reviewe

Physical activity from adolescence to young adulthood: patterns of change, and their associations with activity domains and sedentary time

BackgroundLongitudinal studies demonstrate an average decline in physical activity (PA) from adolescence to young adulthood. However, while some subgroups of adolescents decrease activity, others increase or maintain high or low activity. Activity domains may differ between subgroups (exhibiting different PA patterns), and they offer valuable information for targeted health promotion. Hence, the aim of this study was to identify PA patterns from adolescence to young adulthood; also to explore the associations of (i) changes in PA domains and in sedentary time, (ii) sociodemographic factors, and (iii) self-rated health with diverging PA patterns.MethodsThe observational cohort study data encompassed 254 adolescents at age 15 and age 19. K-means cluster analysis for longitudinal data was performed to identify participant clusters (patterns) based on their accelerometry-measured moderate-to-vigorous PA (MVPA). Logistic regressions were applied in further analysis.ResultsFive PA patterns were identified: inactivity maintainers (n = 71), activity maintainers (n = 70), decreasers from moderate (to low) PA (n = 61), decreasers from high (to moderate) PA (n = 32), and increasers (n = 20).At age 15, participation in sports clubs (SC, 41–97%) and active commuting (AC, 47–75%) was common in all the patterns. By age 19, clear dropout from these activities was prevalent (SC participation mean 32%, AC 31–63%). Inactivity maintainers reported the lowest amount of weekly school physical education.Dropout from SC – in contrast to non-participation in SC – was associated with higher odds of being a decreaser from high PA, and with lower odds of being an inactivity maintainer. Maintained SC participation was associated with higher odds of belonging to the decreasers from high PA, and to the combined group of activity maintainers and increasers; also with lower odds of being an inactivity maintainer. Maintenance/adoption of AC was associated with decreased odds of being an inactivity maintainer. Self-reported health at age 19 was associated with the patterns of maintained activity and inactivity.ConclusionsPA patterns diverge over the transition to adulthood. Changes in SC participation and AC show different associations with diverging PA patterns. Hence, tailored PA promotion is recommended.</p

Itô’s formula for finite variation Lévy processes

Tämän tutkielman tarkoituksena on tarkastella erästä versiota stokastisen integroinnin avaintuloksesta nimeltään Itôn kaava, jolla on tärkeä rooli niin stokastiikan teorian kuin sen erinäisten sovellusten kannalta. Itôn kaavoja voidaan johtaa perustuen useille eri oletuksille sekä tilanteille. Tässä tutkimuksessa oletamme päätuloksena esittettävän Itôn kaavassa käytettävän stokastisen prosessin olevan Lévy-prosessi, joka toteuttaa rajallisen vaihtelun ehdon ja vastaavasti kaavassa käytettävän funtion oletamme jatkuvaksi ja heikosti derivoituvaksi. Tulemme käsittelemään oleellisimmat stokastiikan sekä analyysin esitiedot päätuloksena olevaa Itôn kaavan todistamista varten. Stokastisten prosessien osalta käsittelemme yleisimpiä esimerkkejä Lévy-prosesseista sekä esittelemme niiden tärkeimpiä perusominaisuuksia. Määrittelemme myös Poisson satunnaismitan, jonka tärkeänä erikoistapauksena on muun muuassa hyppymitta. Lisäksi esittelemme joitain kuuluisia stokastiikan tuloksia kuten Lévy-Itô-hajotelma sekä Lévy-Khintchine-kaava. Lisäksi tärkeänä osana Itôn kaavaa määrittelemme ja konstruoimme tarkasti stokastisen integraalin alkaen yksinkertaisista prosesseista ja lopulta yleistäen sen koskemaan laajempaa osaa prosesseista. Jatkona stokastiseen integrointiin tarkastelemme vielä lähemmin erästä stokastisen integraalin laajennusta Poisson satunnaismitan suhteen. Lopuksi esittelemme ja todistamme erään version Itôn kaavasta, joka käyttää oletuksinaan rajallisen vaihtelun ehdon toteuttavaa prosessia, mutta päätuloksesta poiketen olettaa funktioiden olevan heikosti derivoituvuuden sijaan ainoastaan jatkuvasti differentioituvia. Johtuen erityisesti heikosti derivoituvuuden oletuksesta käymme lisäksi läpi joitain reaali- ja funktionaalianalyysin perustuloksia. Erityisenä huomion kohteena ovat tulokset koskien distribuutioteoriaa ja heikkoa derivoituvuutta. Lopuksi näitä esitietoja käyttäen ja oletukset tarkasti määritellen todistamme yksityiskohtaisesti tutkielman päätuloksena olevan version Itôn kaavasta tapauksessa, jossa dimensio on 1.In this thesis we examine a version of the integral result of stochastic integration called Itô's formula which plays an important role both in terms of theory of stochastic and also its various applications. Itô's formulas can be derived based on several different circumstances and situations. In this thesis, we assume that the stochastic process used in Itô's formula presented as the main result is a Lévy process, which fulfills the condition of finite variation, and in addition to this we assume the function used in the formula to be continuous and weakly differentiable. We will introduce the most essential stochastic and analysis prerequisites for proving the Itô formula as the main result. Regarding stochastic processes, we discuss the most common examples of Lévy processes and present their most important basic properties. We also define the Poisson random measure, whose important special case is jump measure. In addition, we present some famous stochastic results such as the Lévy-Itô decomposition and the Lévy-Khintchine formula. Furthermore, as an important part of Itô's formula, we precisely define and construct the stochastic integral starting from simple processes and finally generalizing it into a wider range of processes. As a continuation of stochastic integration, we will take a closer look at an extension of the stochastic integral in terms of the Poisson random measure. Finally, we present and prove a version of Itô's formula, which uses as its assumptions a process fulfilling the finite variation condition, but, in contrast to the main result, assumes that the functions are weakly differentiable instead of only continuously differentiable. Due to the assumption of weak differentiability, we also review some of the basic results of real and functional analysis. Particularly important for the main result are the results regarding distribution theory and weak differentiability. Finally, using this preliminary information and precisely specifying the assumptions, we prove in detail the version of Itô's formula, which is the main result of the thesis, in the case where the dimension is 1

Factors Constraining Teachers’ Wellbeing and Agency in a Finnish University : Lessons from the COVID-19 Pandemic

The COVID-19 pandemic forced teachers to undergo a sudden shift toward technology-enhanced teaching and learning, challenging their capacities for change in many ways. This study explores those factors constraining teachers’ wellbeing and agency that influenced their capacities as teachers in a Finnish university during the first year of the pandemic. Two sets of data were collected, with an online survey in the spring (n = 297) and autumn (n = 246) of 2020. At both times, challenges with workload, time management, and interactions with colleagues were found to be the most constraining factors. Difficulties with work–life balance and home office facilities seemed more of an issue in the spring, whereas transforming teaching and adopting new technological tools were reported as more burdensome in the autumn. The findings show the need for teachers to be heard and holistically supported, particularly when extensive changes in teaching arrangements are expected on a rapid schedule.peerReviewe

The focus and timing of gaze matters : Investigating collaborative knowledge construction in a simulation-based environment by combined video and eye tracking

Although eye tracking has been successfully used in science education research, exploiting its potential in collaborative knowledge construction has remained sporadic. This article presents a novel approach for studying collaborative knowledge construction in a simulation-based environment by combining both the spatial and temporal dimensions of eye-tracking data with video data. For this purpose, we have investigated two undergraduate physics student pairs solving an electrostatics problem in a simulation-based environment via Zoom. The analysis of the video data of the students’ conversations focused on the different collaborative knowledge construction levels (new idea, explication, evaluation, and non-content-related talk and silent moments), along with the temporal visualizations of the collaborative knowledge construction processes. The eye-tracking data of the students’ gaze, as analyzed by epistemic network analysis, focused on the pairs’ spatial and temporal gaze behavior. We illustrate how gaze behavior can shed light on collaborative knowledge construction in terms of the quantity of the talk (e.g., gaze behavior can shed light on the different activities of the pairs during the silent moments), quality of the talk (e.g., gaze behavior can shed light on the different approaches when constructing knowledge on physical phenomena), and temporality of collaborative knowledge construction processes [e.g., gaze behavior can shed light on (the lack of) attempts to acquire the supporting or contrasting evidence on the initial ideas on the physical phenomena]. We also discuss the possibilities and limitations of gaze behavior to reveal the critical moments in the collaborative knowledge construction processes.peerReviewe

Psychosocial and health behavioural characteristics of longitudinal physical activity patterns: a cohort study from adolescence to young adulthood

Abstract Background The decline in physical activity (PA) during adolescence is well-established. However, while some subgroups of adolescents follow the general pattern of decreased activity, others increase or maintain high or low activity. The correlates and determinants of different PA patterns may vary, offering valuable information for targeted health promotion. This study aimed to examine how psychosocial factors, health behaviours, and PA domains are associated with longitudinal PA patterns from adolescence to young adulthood. Methods This prospective study encompassed 254 participants measured at mean ages 15 and 19. Device-measured moderate-to-vigorous PA was grouped into five patterns (activity maintainers, inactivity maintainers, decreasers from moderate to low PA, decreasers from high to moderate PA, increasers) via a data-driven method, K-Means for longitudinal data. Multinomial logistic regression was used to analyse the associations between health behaviours, psychosocial factors, PA domains, and different PA patterns. Results A lack of sports club participation characterised inactivity maintainers throughout adolescence. Difficulties in communicating with one’s father at age 15 were associated with higher odds of belonging to inactivity maintainers and to decreasers from moderate to low PA. Lower fruit and vegetable consumption at age 19 was also related to increased odds of belonging to the groups of inactivity maintainers and decreasers from moderate to low PA. Smoking at age 19 was associated with being a decreaser from moderate to low PA. Conclusions Diverse factors characterise longitudinal PA patterns over the transition to young adulthood. Sports club participation contributes to maintained PA. Moreover, a father-adolescent relationship that supports open communication may be one determinant for sustained PA during adolescence. A healthier diet and non-smoking as a young adult are associated with more favourable PA development

Longitudinal physical activity patterns and the development of cardiometabolic risk factors during adolescence

Purpose: To examine the associations between longitudinal physical activity (PA) patterns and the development of cardiometabolic risk factors from adolescence to young adulthood.Methods: This cohort study encompassed 250 participants recruited from sports clubs and schools, and examined at mean age 15 and 19. Device-measured moderate-to-vigorous PA was grouped into five patterns (via a data-driven method, using inactivity maintainers as a reference). The outcomes were: glucose, insulin, homeostasis model assessment for insulin resistance (HOMA-IR), total cholesterol, HDL and LDL cholesterol, triglycerides, blood pressure, and body mass index (BMI). Linear growth curve models were applied with adjustment for sex, age, fruit/vegetable consumption, cigarette/snuff use, and change in the device wear-time.Results: Insulin and BMI increased among decreasers from moderate to low PA (beta for insulin 0.23, 95% CI 0.03-0.46; beta for BMI 0.90; CI 0.02-1.78). The concentration of HDL cholesterol decreased (beta -0.18, CI -0.31 to -0.05) and that of glucose increased (beta 0.18, CI 0.02-0.35) among decreasers from high to moderate PA. By contrast, among increasers, blood pressure declined (systolic beta -6.43, CI -12.16 to -0.70; diastolic beta -6.72, CI -11.03 to -2.41).Conclusions; Already during the transition to young adulthood, changes in PA are associated with changes in cardiometabolic risk factors. Favorable blood pressure changes were found among PA increasers. Unfavorable changes in BMI, insulin, glucose, and HDL cholesterol were found in groups with decreasing PA. The changes were dependent on the baseline PA and the magnitude of the PA decline.Peer reviewe

Longitudinal physical activity patterns and the development of cardiometabolic risk factors during adolescence

Abstract Purpose: To examine the associations between longitudinal physical activity (PA) patterns and the development of cardiometabolic risk factors from adolescence to young adulthood. Methods: This cohort study encompassed 250 participants recruited from sports clubs and schools, and examined at mean age 15 and 19. Device-measured moderate-to-vigorous PA was grouped into five patterns (via a data-driven method, using inactivity maintainers as a reference). The outcomes were: glucose, insulin, homeostasis model assessment for insulin resistance (HOMA-IR), total cholesterol, HDL and LDL cholesterol, triglycerides, blood pressure, and body mass index (BMI). Linear growth curve models were applied with adjustment for sex, age, fruit/vegetable consumption, cigarette/snuff use, and change in the device wear-time. Results: Insulin and BMI increased among decreasers from moderate to low PA (β for insulin 0.23, 95% CI 0.03–0.46; β for BMI 0.90; CI 0.02–1.78). The concentration of HDL cholesterol decreased (β −0.18, CI −0.31 to −0.05) and that of glucose increased (β 0.18, CI 0.02–0.35) among decreasers from high to moderate PA. By contrast, among increasers, blood pressure declined (systolic β −6.43, CI −12.16 to −0.70; diastolic β −6.72, CI −11.03 to −2.41). Conclusions: Already during the transition to young adulthood, changes in PA are associated with changes in cardiometabolic risk factors. Favorable blood pressure changes were found among PA increasers. Unfavorable changes in BMI, insulin, glucose, and HDL cholesterol were found in groups with decreasing PA. The changes were dependent on the baseline PA and the magnitude of the PA decline