Associations of objectively measured sedentary behavior and physical activity with cognitive function among older Japanese adults: An isotemporal substitution model / 体力科学

Increasing light-intensity physical activity (LPA) or moderate-to-vigorous physical activity (MVPA) and decreasing sedentary behavior (SB) are important to maintain cognitive function in older adults. However, there is a lack of studies examining the influence of replacing time spent in SB, LPA and MVPA on cognitive function. Therefore, this study applied an isotemporal substitution (IS) model approach to examine the associations of objectively measured SB, LPA, and MVPA on multiple cognitive functions in older adults. We analyzed data from 145 older persons (mean age, 75.1 ± 4.5 years; 61.4% women) in Kasama City, Japan. We assessed SB, LPA, and MVPA for seven consecutive days with a triaxial accelerometer. To evaluate the cognitive function, we used the Five-Cog test (character position referencing task, category cued recall task, clock drawing task, animal name listing task, and analogy task). The IS model of the multiple regression analysis was used to examine the effects of replacing time spent on one activity type with 30 minutes per day of SB, LPA, and MVPA on multiple cognitive functions, adjusting for age, gender, body mass index, education, smoking, sleep duration, history of stroke, medication for hypertension, dyslipidemia, and diabetes and accelerometer wear time. The results showed that reallocation from SB to LPA was significantly related to the category cued recall task score (B = 0.69, 95% confidence interval 0.07 - 1.31). In contrast, other reallocations were not associated with any cognitive tasks. The results suggest that substituting SB with LPA is positively associated with verbal episode memory among older Japanese adults.

Consciousness of training body part(s) by showing a picture of an exercise to young inexperienced people: A case of squatting exercises / 体力科学

The aim of the present study was to investigate the consciousness among young people (n = 494) of training body part(s) by showing participants a picture of an exercise, through a questionnaire-based survey. Participants were shown a picture of a Back Squat, and were asked which body part(s) they felt was being trained in the picture. Participants who had no experience of doing squatting exercises (NO-SQUAT group, n = 102) and participants who were experienced in terms of doing squatting exercises and weight training under appropriate supervision (INSTRUCTED group, n = 146) were selected for the analysis. On seeing the picture, more than half of the NO-SQUAT group felt that the Back Squat was to train not only their lower body but also another body part(s); among these participants, approximately 70% felt that a Back Squat was appropriate to train their upper torso and arms too. Further, the NO-SQUAT group had made significantly fewer attempts to consciously train their gluteal and knee flexor muscles, and had made significantly more attempts to consciously train their upper torso and arms during the squatting exercises than the INSTRUCTED group had. These results suggest that to do exercises by referring to only a picture may result in the participants not properly understanding how the body part(s) should be trained during exercise. Therefore, to enhance the benefits of training, individuals need to be instructed, under appropriate supervision, on correct technique as well as knowledge about the exercise.