Adolescent Cardiorespiratory Fitness and Future Work Ability.

Importance: Although research indicates that low fitness in youth is associated with a higher risk of chronic disability in men, the association of fitness in adolescence with work ability in working men and women remains unknown. Objective: To examine the associations of adolescent health-related physical fitness with future work ability. Design, Setting, and Participants: This 45-year observational cohort study, conducted in Finland, examined the direct and indirect longitudinal associations of objectively measured health-related fitness in adolescence (in 1976) with self-reported work ability and sickness absence in early middle age (in 2001) and the Work Ability Index in late middle age (in 2021). A countrywide stratified random baseline sample included fitness measurements for cardiorespiratory fitness (CRF) (running 1.5 km for girls and 2 km for boys), musculoskeletal fitness (MF; standing broad jump and sit-ups for both sexes, pull-ups for boys, and flexed-arm hang for girls), and height and weight, from which body mass index (BMI) was calculated. Structural equation modeling-based path analysis, adjusted for age and sex at baseline and for educational level, work-related physical strain, and leisure-time physical activity in late middle age, was conducted. Data analysis was performed from January to July 2023. Main Outcomes and Measures: Self-reported work ability was measured with structured questions in early middle age and with the validated Work Ability Index in late middle age. Results: The final sample from longitudinal analyses (1207 individuals; 579 [48%] male individuals) consisted of participants with fitness measurement from age 12 to 19 years, and work ability assessment from age 37 to 44 years and/or age 57 to 64 years. Higher adolescent CRF was associated with higher work ability (839 participants; ß = 0.12; 95% CI, 0.01 to 0.22; P = .03) and lower sickness absence (834 participants; ß = -0.07; 95% CI, -0.12 to -0.02; P = .004) in early middle age and, indirectly, mediated by work ability in early middle age, with a higher work ability at the end of working age (603 participants; ß = 0.04; 95% CI, 0.001 to 0.08; P = .04). The results remained consistent in both sexes and after adjustment for the confounders. Neither MF nor BMI was associated with work ability (MF, 1192 participants; ß = -0.07; 95% CI, -0.17 to 0.03; BMI, 1207 participants, ß = 0.09; 95% CI, -0.004 to 0.19) or sickness absence (MF, 1185 participants, ß = 0.02; 95% CI, -0.03 to 0.06; BMI, 1202 participants, ß = -0.03; 95% CI, -0.09 to 0.03) in early middle age or with late middle age work ability, mediated by work ability in early middle age (MF, 603 participants, ß = -0.02; 95% CI, -0.06 to 0.01; BMI, 603 participants, ß = 0.03; 95% CI, -0.004 to 0.07). Conclusions and Relevance: These findings suggest that low CRF in youth is associated with poor work ability at the middle and end of working life, which highlights the informative and prognostic value of CRF assessment early in youth. Enhancing CRF in the first decades of life might contribute to better work capacity and productivity in the labor force, which would have implications for health, quality of life, society, and the economy.

The association of adolescent fitness with cardiometabolic diseases in late adulthood: A 45-year longitudinal study.

OBJECTIVES: The aim of this study was to examine the associations of adolescent cardiorespiratory fitness (CRF), muscular fitness (MF), and speed-agility fitness (SA) with middle-aged cardiometabolic disease risk and explore sex differences. METHODS: This 45-year prospective cohort study examined the associations between objectively measured fitness at adolescence (12-19 years) and physician-ascertained diabetes mellitus, elevated blood pressure (BP), and coronary heart disease reported either in early (37-44 years) or late (57-64 years) middle age, and self-measurement of waist circumference (WC) in late middle age. Fitness measurements for healthy adolescents in baseline included CRF (1.5 km [girls] and 2 km [boys] run), MF (standing broad jump, sit-ups, pull-ups [boys], and flexed-arm hang [girls]), and SA (50 m dash and 4 × 10 m shuttle run). Logistic regression and general linear models were adjusted for baseline age, sex, and body mass index (BMI), involving data from baseline and at least one follow-up measurement (N up to 1358, 47% males). RESULTS: Adolescent CRF was inversely, and regardless of adiposity, associated with middle age accumulated burden of cardiometabolic conditions in the whole sample (N = 562, ß = -0.10, 95% confidence intervals [CI] [-0.18, -0.03], p = 0.006), and elevated BP in females (N = 256, OR = 0.71, 95% CI [0.51, 0.91]). Overall, we observed stronger associations in females than in males. An inverse association of adolescent MF and SA with middle-aged WC was observed, but it did not show as consistent associations as with CRF. CONCLUSIONS: In this study, adolescent fitness, particularly CRF, was inversely associated with the burden of cardiometabolic conditions up to 45 years. Promotion of fitness in youth may be beneficial in preventing adulthood cardiometabolic diseases.

Leisure-time physical activity from adolescence to late middle age and its associations with the COVID-19 pandemic: A 45-year follow-up.

We aimed to investigate the association of self-reported leisure-time physical activity (LTPA) over a 45-years from adolescence to late middle age mediated by LTPA in early middle age. We also explored whether LTPA in adolescence and early middle age was associated with change in LTPA during the COVID-19 pandemic. We constructed a path model employing questionnaire data from three LTPA measurements (1976, 2001, 2021) including duplicated assessment for pre- and during COVID-19 in 2021. The direct and indirect associations between LTPA in adolescence, early middle and late middle age were investigated, as well as the impact of previous LTPA on change in late middle age LTPA due to the pandemic. The number of participants per assessment was: n = 2083; n = 1468 (71% of the original); n = 878 (42%) and n = 867 (42%), respectively. However, the number varied depending on the path examined. LTPA in adolescence was associated with LTPA in late middle age, although the association was not strong. LTPA decreased significantly during the pandemic. Earlier LTPA was associated with change in LTPA between before and during COVID-19 among males. This study is the first to demonstrate an association between adolescent and late middle age LTPA. However, the association across the 45-years was low.

Individuality in the Early Number Skill Components Underlying Basic Arithmetic Skills.

Early number skills underlie success in basic arithmetic. However, very little is known about the skill profiles among children in preprimary education and how the potential profiles are related to arithmetic development. This longitudinal study of 440 Finnish children in preprimary education (mean age: 75 months) modeled latent performance-level profile groups for the early number skill components that are proposed to be key predictors of arithmetic (symbolic number comparison, mapping, and verbal counting skills). Based on three assessment time points (September, January, and May), four profile groups were found: the poorest-performing (6%), low-performing (16%), near-average-performing (33%), and high-average-performing children (45%). Although the differences between the groups were statistically significant in all three number skill components and in basic arithmetic, the poorest-performing children seemed to have serious difficulties in accessing the semantic meaning of symbolic numbers that was required in the number comparison and mapping tasks in this study. Interestingly, the tasks demanding processing between quantities and symbols also most differentiated the poorest-performing children from the low-performing children. Due to remarkable and stable individual differences in early number skill components, the findings suggest systematic support and progress monitoring practices in preeducational settings to diminish and avoid potential difficulties in arithmetic and mathematics in general.