A Daily Process Analysis of Physical Activity, Sedentary Behavior, and Perceived Cognitive Abilities

Physical activity and cognitive function: moment-to-moment and day-to-day associations

BACKGROUND

The beneficial effect of acute physical exercise on cognitive performance has been studied in laboratory settings and in long-term longitudinal studies. Less is known about these associations in everyday environment and on a momentary timeframe. This study investigated momentary and daily associations between physical activity and cognitive functioning in the context of everyday life.

METHODS

Middle-aged adults (n = 291, aged 40-70) were asked to wear accelerometers and complete ecological momentary assessments for eight consecutive days. Processing speed and visual memory were assessed three times per day and self-rated evaluations of daily cognition (memory, thinking, and sharpness of mind) were collected each night. The number of minutes spent above the active threshold (active time) and the maximum vector magnitude counts (the highest intensity obtained) before each cognitive test and at a daily level were used as predictors of momentary cognitive performance and nightly subjective cognition. Analyses were done with multilevel linear models. The models were adjusted for temporal and contextual factors, age, sex, education, and race/ethnicity.

RESULTS

When participants had a more active time or higher intensity than their average level within the 20 or 60 minutes prior to the cognitive test, they performed better on the processing speed task. On days when participants had more active time than their average day, they rated their memory in the evening better. Physical activity was not associated with visual memory or self-rated thinking and sharpness of mind.

CONCLUSIONS

This study provides novel evidence that outside of laboratory settings, even small increases in physical activity boost daily processing speed abilities and self-rated memory. The finding of temporary beneficial effects is consistent with long-term longitudinal research on the cognitive benefits of physical activity.

Momentary intentions and perceived behavioral control are within-person predictors of sedentary leisure time: preliminary findings from an ecological momentary assessment study in adolescents

Previous studies among adolescents conceptualize behavioral cognitions [e.g., intentions and perceived behavioral control (PBC)] as stable trait-like factors despite evidence suggesting they vary momentarily. We examined whether intentions and PBC momentarily relate to subsequent sedentary time during non-school periods. Healthy adolescents (N = 15, ages 11-15) reported their intentions and PBC regarding sedentary leisure behaviors via ecological momentary assessment (EMA) up to seven times/day for 14 days. Sedentary time in the two hours following each EMA prompt was measured by ActivPAL accelerometers. When participants reported greater sedentary intentions (within-person β = 1.1, 95% CI 0.2, 2.1, p = 0.0213) and sedentary PBC (within-person β = 1.7, 95% CI 0.6, 2.8, p = 0.0029), they accumulated greater sedentary time. This demonstrates that sedentary intentions and PBC are acutely associated with sedentary time among adolescents. Our findings highlight the potential for implementing just-in-time activity interventions among adolescents during at-risk periods within the day, characterized by deviations from one's usual intentions and PBC levels.

Sedentary time among undergraduate students: A systematic review

To systematically review and synthesize all relevant literature to assess the range of average daily sedentary time (ST) of undergraduate students enrolled in university and college programs across the world. Methods: Published, peer-reviewed articles were included if they: (a) were in English; (b) had a study population that consisted entirely of undergraduate students; (c) reported a daily or weekly ST for undergraduate students; and (d) included a measure of ST using a valid sedentary behavior questionnaire or accelerometers. Results: Twenty-three studies were included in the review. A wide range of ST (0.75 to 14.35 hours per day) was reported. Mean ST as measured by domain-specific questionnaires and accelerometers was 11.10 hours per day and 10.69 hours per day, respectively. Conclusion: Findings suggest that some undergraduate students participate in high levels of ST. Additional research, as well as interventions focused on reducing ST among postsecondary students, are needed.

Association of mentally-passive and mentally-active sedentary behaviors with device-measured bouts and breaks of sedentary time in adolescents

Background: Our aim was to analyze the association of self-reported mentally-passive and mentally-active sedentary behaviors with different patterns (bouts and breaks) of device-measured sedentary time in adolescents.

Methods: This was a cross-sectional study conducted among 375 adolescents (177 boys) aged 1015 years. Total time, bouts and breaks of sedentary time were measured through accelerometers. Self-reported sedentary behavior in different activities was summed and divided into mentally-active (playing electronic games, studying and reading) and mentally-passive (watching TV, watching DVD, and using computer for leisure). Bayesian linear regression models were used for association analyses.

Results: Only mentally-passive sedentary behaviors were positively associated with longer bouts [1-4 minutes: mean posterior distribution: -0.431 (95% credible interval: -0.745 to -0.114); =15 minutes: 0.641 (0.122 to 1.222)] and lower number of breaks [-0.138 (-0.228 to -0.044)] of device-measured sedentary time.

Conclusion: Self-reported mentally-passive sedentary behaviors are associated with longer bouts and lower breaks of device-measured sedentary time.

Using Research Electronic Data Capture for Longitudinal Assessment Among Older Adults With Diabetes Enhances Real-Time Data Collection

The aim of this study was to provide evidence on the application of Research Electronic Data Capture for collecting repeated data during a 7-day period among older adults. Fifty-seven adults (≥50 years) with type 2 diabetes were recruited. Participants completed one sleep diary upon awaking and one self-care diary before going to bed each day for 7 days. The diaries were administered via the Research Electronic Data Capture Web-based system and were completed via participants' own electronic devices. Objective compliance rate, time used to complete each diary, and participant experience were described. Approximately 80% (n = 45) of the participants used Research Electronic Data Capture. Among these participants, the noncompliance rate ranged between 0% and 8.9% for the sleep diary and 0% and 13.1% for the self-care diary. Participants spent 4.2 to 8.7 minutes on the sleep diary and 3.5 to 7.1 minutes on the self-care diary. It took the participants a longer time to complete the diaries during the first day than during the following 6 days. Few participants reported technical issues or felt inconvenient or stressful with completing the Research Electronic Data Capture diaries. Overall, the compliance rates were high. Completing the diaries was not time-consuming and participants were largely satisfied with the Research Electronic Data Capture data collection. Research Electronic Data Capture has aided the longitudinal data collection. With adequate training, Research Electronic Data Capture is an efficient tool to collect repeated data among older adults and thus is recommended for future research.

Correlates of sedentary behaviour in university students: A systematic review

High levels of sedentary behaviour are associated with negative health-related outcomes. However, there is limited evidence on the variables influencing sedentary behaviour in university students. The aim of this systematic review was to identify the intrapersonal, interpersonal, environmental, and time correlates of sedentary behaviour in university students. Records from 12 electronic databases were screened by two independent reviewers. Inclusion criteria included: (i) peer-reviewed articles written in English, Spanish, or French; (ii) studies including undergraduate or postgraduate university students; (iii) studies reporting on the association between sedentary behaviour and at least one variable. The protocol is registered in PROSPERO (CRD42017074198). A total of 126 studies published between 1994 and 2017 met the inclusion criteria. The primary measure of sedentary behaviour was self-reported screen time (61%), followed by total sitting time (28%). Most studies were cross-sectional (86%). After excluding high risk of bias studies (58%), only three intrapersonal variables were sufficiently investigated (≥4) to determine an association with sedentary behaviour: physical activity (negative association with sitting time), obesity markers (indeterminate associations with TV viewing), and gender - female (null associations with total sitting time and screen time). Overall, most of the reported correlates of sedentary behaviour were intrapersonal, non-modifiable factors. Further research on modifiable correlates covering all socio-ecologic levels is required to inform future intervention development. In addition, longitudinal studies are needed to enable the identification of determinants. Improvements in designing and reporting future studies are recommended to help strengthen the available evidence and facilitate future reviewing efforts.