Temporal trends in handgrip strength for older Japanese adults between 1998 and 2017

Objective: To estimate temporal trends in handgrip strength (HGS) for older Japanese adults between 1998 and 2017. Design and Methods: Adults aged 60–79 years were included. Annual nationally representative HGS data (n=176,449) for the 19-year study period were obtained from the Japanese Ministry of Education, Culture, Sports, Science and Technology. Temporal trends in mean HGS were estimated by sample-weighted regression models relating the year of testing to mean HGS. National trends in absolute, percent and standardized HGS were estimated by a post-stratified population-weighting procedure. Temporal trends in variability were estimated as the ratio of coefficients of variation (CVs). Results: Collectively, there was a small improvement in mean HGS of 1.4 kg (95%CI: 1.3–1.5), 4.5% (95%CI: 4.3–4.7), or 0.27 standard deviations (95%CI: 0.26–0.28) between 1998 and 2017. The rate of improvement progressively increased over time, with more recent values (post-2008) 1.5-fold larger than earlier values. Gender- and age-related temporal differences were negligible. Variability in HGS declined substantially over time (ratio of CVs [95%CI]: 0.88 [0.86–0.90]), with declines 1.9-fold larger in women compared to men, and 1.7-fold larger in 70–79-year-olds compared to 60–69-year-olds. Conclusions: There has been a small, progressive improvement in mean HGS for older Japanese adults since 1998, which is suggestive of a corresponding improvement in overall strength capacity. The substantial decline in variability indicates that the improvement in mean HGS was not uniform across the population

Temporal trends in 6-minute walking distance for older Japanese adults between 1998 and 2017

Background The 6-minute walking distance (6MWD) is an excellent measure of both functional endurance and health. The primary aim of this study was to estimate temporal trends in 6MWD for older Japanese adults between 1998 and 2017; the secondary aim was to estimate concurrent trends in body size (i.e., height and mass) and self-reported participation in exercise/sport. Methods Adults aged 65–79 years were included. Annual nationally representative 6MWD data (n = 103,505) for the entire period were obtained from the Japanese Ministry of Education, Culture, Sports, Science and Technology. Temporal trends in means (and relative frequencies) were estimated at the gender–age level by best-fitting sample-weighted linear/polynomial regression models, with national trends estimated by a post-stratified population-weighting procedure. Temporal trends in distributional variability were estimated as the ratio of coefficients of variation. Results Between 1998 and 2017 there was a steady, moderate improvement in mean 6MWD (absolute = 45 m (95% confidence interval (CI): 43–47); percent = 8.0% (95%CI: 7.6–8.4); effect size = 0.51 (95%CI: 0.48–0.54)). Gender- and age-related temporal differences in means were negligible. Variability in 6MWD declined substantially (ratio of coefficients of variation = 0.89, 95%CI: 0.87–0.92), with declines larger for women compared to men, and for 75–79-year-olds compared to 65–74-year-olds. Correspondingly, there were moderate and negligible increases in mean height and mass, respectively, and negligible increases in the percentage who participated in exercise/sport at least 3 days per week and at least 30 min per session. Conclusions There has been a steady, moderate improvement in mean 6MWD for older Japanese adults since 1998, which is suggestive of corresponding improvements in both functional endurance and health. The substantial decline in variability indicates that the temporal improvement in mean 6MWD was not uniform across the distribution. Trends in 6MWD are probably influenced by corresponding trends in body size and/or participation in exercise/sport

Different patterns of walking and postprandial triglycerides in older women

Purpose: Although a single bout of continuous exercise (≥30 min) reduces postprandial triglyceride (TG), little evidence is available regarding the effect of multiple short (≤10 min) bouts of exercise on postprandial TG in individuals at increased risk of cardiovascular diseases. This study compared the effect of different patterns of walking on postprandial TG in postmenopausal, older women with hypertriglyceridemia. Methods: Twelve inactive women (aged 71 ± 5 yrs, mean ± S.D.) with hypertriglyceridemia (fasting TG ≥ 1.70 mmol/L) completed three, one-day laboratory-based trials in a random order: 1) control, 2) continuous walking, and 3) multiple short bouts of walking. On the control trial, participants sat in a chair for 8 hours. For the walking trials, participants walked briskly in either one 30-min bout in the morning (0900-0930) or twenty 90-sec bouts over 8 hours. Except for walking both exercise trials mimicked the control trial. In each trial, participants consumed a standardized breakfast (0800) and lunch (1100). Venous blood samples were collected in the fasted state and at 2, 4, 6 and 8 h after breakfast. Results: The serum TG incremental area under the curve was 35% and 33% lower on the continuous and multiple short bouts of walking trials than the control trial (8.2 ± 3.1 vs 8.5 ± 5.4 vs 12.7 ± 5.8 mmol∙8h/L respectively, main effect of trial: ES = 0.459, P = 0.001). Conclusions: Accumulating walking in short bouts limits postprandial TG in at-risk, inactive older women with fasting hypertriglyceridemia

Sports Science and Efforts towards Sub-Two Hour Marathon Performance

Performance in different athletic activities has continued to improve over time, with some athletes from diverse parts of the world registering new world records from time to time. With stiff competition from athletes from different parts of the world, constant upgrading of sports science based approaches to training and competition are employed to achieve more success. However, some approaches used to improve sports performance may pose ethical concerns and may challenge sports as a concept of celebrating natural human abilities. This book chapter interrogates the factors associated with efforts towards improvement of performance in endurance sports events, with a specific focus on marathon races, and the future implications for training, competition, and the nature of sports. While the interplay between nature and nurture determines the unique psychophysiological responses to training and competition, technological exploits leading to advanced sports products coupled with favourable natural and/or manipulated internal (body) and external environmental conditions will ensure continued improvement in performance. However, there is a need to censor commercial interest as well as safeguard safety and the nature of sports as a medium to celebrate natural human abilities

Sexual Function Is an Indicator of Central Arterial Stiffness and Arterial Stiffness Gradient in Japanese Adult Men

BackgroundAs arterial stiffness increases in the absence of subjective symptoms, a personal indicator that reflects increased risk of cardiovascular disease is necessary. Penile erection is regulated by vascular function, and atherosclerosis affects the penile artery earlier than it affects the coronary and carotid arteries. Therefore, we hypothesized that deterioration of erectile function could be a marker of increased risk for cardiovascular disease. To test our hypothesis, we assessed erectile function and arterial stiffness in a cross‐sectional study.Methods and ResultsCarotid‐femoral pulse wave velocity (PWV), brachial‐ankle PWV, femoral‐ankle PWV, and arterial stiffness gradient (PWV ratio: carotid‐femoral PWV/femoral‐ankle PWV) were measured as indexes of central, systemic, and peripheral arterial stiffness and peripheral organ damage, respectively, in 317 adult men. In addition, erectile function was assessed by using the questionnaire International Index of Erectile Function 5 (a descending score indicates worsening of erectile function). The scores of male sexual function were inversely correlated with carotid‐femoral PWV (rs=−0.41), brachial‐ankle PWV (rs=−0.35), femoral‐ankle PWV (rs=−0.19), and PWV ratio (rs=−0.33). Furthermore, multivariate linear regression analyses revealed that International Index of Erectile Function 5 scores were significantly associated with carotid‐femoral PWV (β=−0.22) and PWV ratio (β=−0.25), but not with brachial‐ankle PWV and femoral‐ankle PWV.ConclusionsOur results indicated that erectile function is independently associated with central arterial stiffness and peripheral organ damage. These findings suggest that male sexual function could be an easily identifiable and independent marker of increased central arterial stiffness and peripheral organ damage

Classroom Standing Desks and Time-Series Variation in Sedentary Behavior and Physical Activity among Primary School Children

The purpose of the present study was to examine the effects of height-adjustable standing desks on time-series variation in sedentary behavior (SB) among primary school children. Thirty-eight children aged 11–12 years (22 boys and 16 girls) from two classes at a primary school in Nagano, Japan, participated in this study. One class was allocated as the intervention group and provided with individual standing desks for 6 months, and the other was allocated as the control group. Time spent in SB, light-intensity physical activity (LPA), and moderate-to-vigorous-intensity physical activity (MVPA) was measured using accelerometers (ActiGraph) at baseline and follow-up. Time spent in SB was significantly lower by 18.3 min/day on average in the intervention class at follow-up (interaction effects: F(1, 36) = 4.95, p = 0.035, η2 = 0.082). This was accompanied by a significant increase in time spent in MVPA (+19.9 min/day on average). Our time-series analysis showed significant decreases in SB during school time, while no change in SB was found during non-school time. This result indicates that the use of standing desks promotes an overall reduction in SB with no compensatory increase during non-school time

Sociocultural Dimensions of Children’s Physical Activity in Contemporary Pastoralist Maasai Society

Children’s physical activity (CPA) in low- and middle-income regions has received increasing attention, but research is still very limited. This study explores the CPA in contemporary pastoralist Maasai society in rural Kenya by considering its sociocultural dimensions. The physical activity of 25 children (15 girls and 10 boys) was documented with mixed methods, including an epidemiological assessment of the CPA and semi-structured interviews with the targeted children regarding their daily activities. These methods were integrated with the ethnographic data on children’s socialization in the same area. Results showed a very high level of moderate-to-vigorous physical activity (MVPA) of these children with significant gender differences especially outside school. Children reported their continued social participation in local gender–age labor divisions outside of school. As their activities outside school strongly contributed to their empirical learning of local knowledge and skills, a high MVPA plays an active role in enhancing the children’s ability to access and manage livestock and different natural resources. Findings from this study first show that the CPA is not merely physical, but also has significant sociocultural meanings in the process of in situ learning of local wisdom. We call more attention to children’s social roles in future investigations of CPA among less examined populations

Classroom Standing Desks and Time-Series Variation in Sedentary Behavior and Physical Activity among Primary School Children

The purpose of the present study was to examine the effects of height-adjustable standing desks on time-series variation in sedentary behavior (SB) among primary school children. Thirty-eight children aged 11−12 years (22 boys and 16 girls) from two classes at a primary school in Nagano, Japan, participated in this study. One class was allocated as the intervention group and provided with individual standing desks for 6 months, and the other was allocated as the control group. Time spent in SB, light-intensity physical activity (LPA), and moderate-to-vigorous-intensity physical activity (MVPA) was measured using accelerometers (ActiGraph) at baseline and follow-up. Time spent in SB was significantly lower by 18.3 min/day on average in the intervention class at follow-up (interaction effects: F(1, 36) = 4.95, p = 0.035, η2 = 0.082). This was accompanied by a significant increase in time spent in MVPA (+19.9 min/day on average). Our time-series analysis showed significant decreases in SB during school time, while no change in SB was found during non-school time. This result indicates that the use of standing desks promotes an overall reduction in SB with no compensatory increase during non-school time

Physical fitness before and during the COVID-19 pandemic: Results of annual national physical fitness surveillance among 16,647,699 Japanese children and adolescents between 2013 and 2021

Background: Limited nationally representative evidence is available on temporal trends in physical fitness (PF) for children and adolescents during the coronavirus disease 2019 (COVID-19) pandemic. The primary aim was to examine the temporal trends in PF for Japanese children and adolescents before and during the COVID-19 pandemic. The secondary aim was to estimate the concurrent trends in body size (measured as body mass and height) and movement behaviors (exercise, screen, and sleep time). Methods: Census PF data for children in Grade 5 (aged 10–11 years) and adolescents in Grade 8 (aged 13–14 years) were obtained for the years 2013–2021 from the National Survey of Physical Fitness, Athletic Performance, and Exercise Habits in Japan (n = 16,647,699). PF and body size were objectively measured, and movement behaviors were self-reported. Using sample-weighted linear regression, temporal trends in mean PF were calculated before the pandemic (2013–2019) and during the pandemic (2019–2021) with adjustments for age, sex, body size, and exercise time. Results: When adjusted for age, sex, body size, and exercise time, there were significant declines in PF during the pandemic, with the largest declines observed in 20-m shuttle run (standardized (Cohen's) effect size (ES) = −0.109 per annum (p.a.)) and sit-ups performance (ES = −0.133 p.a.). The magnitude of the declines in 20-m shuttle run and sit-ups performances were 18- and 15-fold larger, respectively, than the improvements seen before the pandemic (2013–2019), after adjusting for age, sex, body size, and exercise time. During the pandemic, both body mass and screen time significantly increased, and exercise time decreased. Conclusion: Declines in 20-m shuttle run and sit-ups performances suggest corresponding declines in population health during the COVID-19 pandemic

The Changes in Visual Acuity Values of Japanese School Children during the COVID-19 Pandemic

The coronavirus disease 2019 (COVID-19) pandemic may result in a greater decrease in visual acuity (VA) among Japanese children. Our study aimed to examine Japanese children’s VA during the pandemic. VA data were collected using standard eye tests during school health check-ups conducted in 2019 and 2020 on 5893 children, in seven public elementary schools and four public junior high schools in Tokyo, Saitama, Kanagawa, and Shizuoka. VA changes were statistically analyzed. The relationship between the survey year and poor VA yielded a significant regression coefficient for the surveyed years in elementary and junior high school students. The 2019 VA value and VA change from 2019 to 2020 demonstrated a significant regression coefficient in elementary school students with VAs of “B (0.7–0.9)” and “C (0.3–0.6)”, and junior high school students with VAs of “B”, “C”, and “D (<0.3)”. An analysis of the relationship between the survey year and eye laterality of VA yielded a significant regression coefficient in the surveyed years for elementary (OR, 1.516; 95% CI, 1.265–1.818) and junior high school students (OR, 1.423; 95% CI, 1.136–1.782). Lifestyle changes during the COVID-19 pandemic might have affected VA and eye laterality in Japanese children