We reviewed the physical activity research conducted during the SARS and COVID-19 pandemic, and investigated the impact of COVID-19 pandemic on physical activity. According to an international study using smartphone applications, the number of steps decreased the most under lockdown and restrictions compared to the pre-COVID-19 pandemic, but the extent of the decrease differed between countries. In Japan, the number of daily steps decreased by about 30% around the time of the declaration of the state of emergency in April compared to the COVID-19 epidemic in early February. In addition, a body of Internet surveys reported an increase in sedentary behavior and a decrease in moderate-to-vigorous physical activity during the COVID-19 pandemic. However, these studies only represent a temporal situation under lockdown and restrictions. Therefore, the impact of the COVID-19 pandemic and lifestyle changes on physical activity needs to be determined with a long-term perspective in the future. Although Internet surveys and wearable device-based physical activity research is useful for understanding the situation in real time, caution should be paid to interpret the data because of possible selection bias.
Objective: The present study conducted a comprehensive review of the evaluation methods for awareness and knowledge of physical activity guidelines in adults, as well as to observe the relationship between awareness and knowledge of these guidelines and physical activity levels. In this review, we summarize the trends in Japanese and international research in this field and to propose topics for future research.
Methods: PubMed, PsycINFO, and Ichu-shi were used to perform a literature search. The search terms included keywords such as “guidelines”, “awareness or knowledge”, and “physical activity or sedentary behavior”, as specifically designed search expressions. Literature screening was based on set eligibility criteria, and the core characteristics of the studies were extracted and summarized.
Results: Twenty-five articles published after 2001 were selected, based on the screening. The evaluation method for the awareness of the physical activity guidelines was roughly divided into unprompted and prompted recall. Although a positive association was observed between unprompted recall and physical activity, the results proved inconsistent in cases of prompted recall. The evaluation methods for guideline knowledge varied, with many of the evaluation methods asking participants to respond numerically to the recommended amount of physical activity. A positive relationship with physical activity levels was recognized in many of the studies in which participants were asked to respond to the recommendations either numerically or through multiple options. Only one study evaluated sedentary behavior.
Conclusion: The evaluation methods for quantifying awareness and knowledge of the physical activity guidelines varied among studies. The results were inconsistent on the relationship between awareness or knowledge of the guidelines and physical activity levels. Future studies should standardize these evaluation methods, and accumulate studies that evaluate physical activity and sedentary behavior using objective measurements.
Objective: The rates in the competition result (the rates of winning) of boat racers was regarded as the outcome, and related factors were examined by a cohort survey.
Methods: The subjects were 110 boat racers (mean age 42.7 ± 7.5 years old). The rates of winning from racing results conducted at the baseline (BL) and three years later were used. Changes in the rates of winning were calculated as (the rates of winning three years later – BL the rates of winning) / BL the rates of winning x 100, which was used as the outcome. Multiple regression analysis was performed on the relationship between the rate of change of the three-year rates of winning and sex, variables at BL (the rates of winning, age, weight, and dynamic balance capability), and the amount of change in weight and dynamic balance capability.
Result: The rate of change in the rates of winning was inversely associated with age and weight at BL (p< 0.05). In contrast, sex, and dynamic balance capability were not admitted as related factors in terms of their significance.
Conclusion: The three-year rate of change in the competition result of boat racers was inversely associated with age and weight at BL.
Objective: This study examined the association between use of heating and sedentary behavior (SB) and physical activity (PA) at home among Japanese adults in winter.
Methods: This cross-sectional study was conducted from November to April from 2014 to 2017. Participants (n=3,874) who intended to conduct insulation retrofitting were recruited by construction companies from 46 prefectures excluding Okinawa Prefecture and wore an accelerometer on their waist for 2 weeks. The association between heating use and log-transformed SB and PA at home was analyzed using a sex-stratified multilevel model (random-intercept model) with 3 levels; day-level variables (e.g., indoor temperature and log-transformed accelerometer wear time as an offset), nested within individual-level (e.g., age and body mass index), and nested within household-level (e.g., household income, number of housemates). The degree of association with the dependent variable was given by exponential transforming the unstandardized regression coefficient.
Results: Data from 3,482 participants were analyzed. In the multilevel model, not using a kotatsu was associated with about 2% shorter SB time [men: exp(B)=0.98, p=0.022; women: exp(B)=0.98, p=0.020], an about 10% greater number of breaks in SB time [men: exp(B)=1.10, p=0.001; women: exp(B)=1.11, p<0.001], and 5-7% greater PA [men: exp(B)=1.07, p=0.005; women: exp(B)=1.05, p=0.012] than using a kotatsu. Heating the changing room was also related to shorter SB time, a greater number of breaks in SB time and greater PA in men and women.
Conclusions: Not using a kotatsu and heating the changing room were associated with shorter SB and greater PA at home. Warming by heating the entire home, rather than partially heating just the living room, may decrease SB and increase PA in winter.
Objective: The purpose of this study was to examine whether male staff members’ physical activity increased and whether it was maintained by an intervention using the teaching materials we created.
Methods: The teaching material was created by us in collaboration with the Art and Design Department, University of Tsukuba. Players were required to increase the amount of physical activity in order to gain an advantage in a certain game. The subjects were 11 male staff members aged 24 to 48 years, with median age 34.0 years (interquartile range = 33.5, 39.5 years) from the regional university and the regional university hospital. The intervention game was played for six weeks, 4 times (1 time / 2 weeks, 30 minutes / 1 time). The period of two weeks before the intervention was chosen as the baseline period, and the 12 weeks after the intervention as the carry-over observation period for the intervention effect. Subjects were randomly assigned to two groups, an intervention group and a control group, but the effects of changes in physical activity in the control group were not reflected in the game. We distributed a 3-axis accelerometer to all the subjects to measure their physical activity.
Results: In the comparison between the groups with moderate and vigorous intensity activity time (median), the change during the intervention period was +1.6 minutes / day in the intervention group compared with +0.2 minutes / day in the control group. Regarding changes over time, the rate of change 12 weeks after the intervention was +48% in the intervention group and +10% in the control group compared to the baseline period.
Conclusion: Physical activity levels of male staff members can be increased by an intervention using our teaching material and may be maintained over the medium term after the intervention.
Objective: We aimed to describe maternal physical activity level from pre-pregnancy up to 3.5 years postpartum among Japanese women. Moreover, we explored the factors associated with keeping the level of physical activity lower after delivery.
Methods: A total of 1,874 women who agreed to participate in the Miyagi regional adjunct study of The Japan Environment and Children’s Study were included. Physical activity was measured before pregnancy, during pregnancy, and 1.5 and 3.5 years postpartum using IPAQ short version, and was classified into two categories: low physical activity and moderate-high physical activity. Factors that contributing to keeping the level of physical activity lower at 1.5 and 3.5 years postpartum were maternal age, marital status, education, working status, parity, re-pregnancy after the targeted child, pre-pregnancy BMI, exercise experience and physical activity before and during pregnancy. We performed a Poisson regression analysis.
Results: There were 969 (51.7%) women with lower physical activity level at pre-pregnancy, 1,209 (64.5%) during pregnancy and 1,724 (92.0%) at 1.5 years postpartum. In addition, there were 1,223 (65.3%) women with lower physical activity level at 3.5 years postpartum. Factors contributed to keeping the level of physical activity lower at 1.5 and 3.5 years postpartum were high maternal age, highly educated women, current worker, former worker and non-worker, no previous exercise experience, and low physical activity level before and during pregnancy.
Conclusion: Compared to pre-pregnancy, larger proportion of women had lower level of physical activity during pregnancy, and it was even higher at 1.5 years postpartum. At 3.5 years postpartum, many women still had lower level of physical activity. In addition, high maternal age, highly educated women, current worker, former worker and non-worker, no previous exercise experience, and low physical activity level before and during pregnancy were significantly likely to keep the level of physical activity lower at 1.5 and 3.5 years postpartum.
The 2020 Yokohama Sport Conference, an international conference in harmony with the 2020 Olympic and Paralympic Games, was initially planned to be held in Yokohama from 8 to 12 September, 2020. However, the COVID-19 pandemic significantly affected the conference; the conference style and dates were changed and many programs were altered or cancelled. All sessions in which Japanese Association of Exercise Epidemiology was involved were also cancelled. Then, owing to the stakeholders’ passions, kind understanding and help, we replanned and held online lectures and a talk by Dr. Fiona Bull (Head of Physical Activity Unit, Department of Health Promotion, Division of Healthier Populations, World Health Organization) and Dr. Daichi Suzuki (Commissioner, Japan Sports Agency) on September 9, 2020 as a public program, connecting Switzerland and Japan in real-time. As we could not have enough time for discussions among participants of the public program, we also held an online reflection session on the following day. Here, we summarize the process and contents of these sessions and discuss future perspectives, based on the findings from the sessions as an implementation of dissemination of exercise epidemiology.
Background: In longevity societies, one of the most serious social issues is sarcopenia and/or frailty. Preventing them is important for maintaining independence and quality of life in the older population. This study investigated the effect of a self-monitoring comprehensive geriatric intervention programme (CGIP) on physical function and muscle size in community-dwelling older adults. We compared the effects of a CGIP using weekly class-styled (CS) sessions and a home-based (HB) programme.
Methods: The 526 participants were randomized into one of two groups (CS 251, HB 275) based on their residential districts. We conducted a 12 week CGIP, which consisted of low-load resistance exercise, physical activity increments, oral function improvements, and a nutritional guide. All participants were encouraged to attend two 90 min lectures that included instructions on the CGIP. They were provided with exercise materials (triaxialaccelerometers/pedometers, ankle weights, and elastic bands) and diary logs. The CS group attended 90 min weekly sessions and independently executed the programme on other days, whereas the HB group only received instructions on how to execute the programme. Physical functions, such as knee extension strength (KES), normal and maximum walking speed, the timed up-and-go test, and anterior thigh muscle thickness (MT), were measured and analysed using intention-to-treat analysis before and after the 12 week intervention.
Results: Of the 526 participants identified, 517 (CS 243 age 74.0 ± 5.4 women 57.2%, HB 274 age 74.0 ± 5.6 women 58.8%) were enrolled. Nine (CS 8, HB 1) were excluded from the analysis because they did not participate in the pre-intervention measurements. Both interventions significantly improved KES (CS 18.5%, HB 10.6%), normal walking speed (CS 3.7%, HB 2.8%), and MT (CS 3.2%, HB 3.5%). Greater improvement of KES was observed in the CS group (P = 0.003). Maximum walking speed (CS 4.7%, HB 1.8%; P = 0.001) and timed up-andgo (CS -4.7%, HB -0.2%; P < 0.001) significantly improved in the CS group only.
Conclusions: The intervention was effective in preventing sarcopenia and/or frailty. Most physical functions and MT improved after both interventions. The HB intervention is cost-effective and may help prevent sarcopenia and/or frailty in the large older population.