Physical Activity and Inhibitory Control: The Mediating Role of Sleep Quality and Sleep Efficiency

Sedentary behavior and lifespan brain health

Higher levels of physical activity are known to benefit aspects of brain health across the lifespan. However, the role of sedentary behavior (SB) is less well understood. In this review we summarize and discuss evidence on the role of SB on brain health (including cognitive performance, structural or functional brain measures, and dementia risk) for different age groups, critically compare assessment approaches to capture SB, and offer insights into emerging opportunities to assess SB via digital technologies. Across the lifespan, specific characteristics of SB (particularly whether they are cognitively active or cognitively passive) potentially act as moderators influencing the associations between SB and specific brain health outcomes. We outline challenges and opportunities for future research aiming to provide more robust empirical evidence on these observations.

Self-reported physical activity and sleep quality is associated with working memory function in middle-aged and older adults during the COVID-19 pandemic

While previous work has shown a positive relationship between cognitive performance and lifestyle factors in younger adults, evidence for this relationship among middle-aged and older adults has been mixed. The current study aimed to further test the relationship among physical activity, sleep quality, and memory performance in middle-aged and older adults, and to test whether this relationship holds up during the COVID-19 pandemic. Our results showed that physical activity was associated with better sleep quality and better working memory performance, and better sleep quality was associated with better working memory and self-perceptions of everyday memory abilities. Additionally, we found that the effects of physical activity on working memory were partially mediated by sleep quality. While these effects were small and only correlational in nature, they lend further support to the notion that sleep quality and physical activity are beneficial to memory later in life, even during a global pandemic.

Sleep quality and executive function in a diverse sample of healthy young adults

Few studies examine the relationship between sleep and executive function in diverse samples of young adults. Our research aims to fill this gap by analyzing how self-reported sleep quality is related to informant-rated executive function as a whole and its working memory component in a diverse sample of 29 healthy college students. Using the self-report measure, the Pittsburgh Sleep Quality Index (PSQI), we divided our sample into two groups based on cutoff criteria (score ≥5: poor sleep): good sleep quality (n = 11) and poor sleep quality (n = 18). Participants were on average 20.86 years old. Informants rated participants' executive functioning and working memory using the Frontal Systems Behavior Scale (FrSBe) and Behavior Rating Inventory of Executive Function (BRIEF). Individuals in the poor sleep quality group were reported as having significantly worse executive function and working memory scores. Young adult college students who report less than 7 hours of sleep per night have lower scores on informant measures of working memory and executive function. This study raises awareness about how self-reported sleep experiences are related to other's observation of cognitive abilities in everyday life in a diverse young adult sample.

Alexa, let's train now! - A systematic review and classification approach to digital and home-based physical training interventions aiming to support healthy cognitive aging

BACKGROUND

There is mounting evidence that regular physical activity is an important prerequisite for healthy cognitive aging. Consequently, the finding that almost one-third of the adult population does not reach the recommended level of regular physical activity calls for further public health actions. In this context, digital and home-based physical training interventions might be a promising alternative to center-based intervention programs. Thus, this systematic review aimed to summarize the current state of the literature on the effects of digital and home-based physical training interventions on adult cognitive performance.

METHODS

In this pre-registered systematic review (PROSPERO; ID: CRD42022320031), 5 electronic databases (PubMed, Web of Science, PsycInfo, SPORTDiscus, and Cochrane Library) were searched by 2 independent researchers (FH and PT) to identify eligible studies investigating the effects of digital and home-based physical training interventions on cognitive performance in adults. The systematic literature search yielded 8258 records (extra 17 records from other sources), of which 27 controlled trials were considered relevant. Two reviewers (FH and PT) independently extracted data and assessed the risk of bias using a modified version of the Tool for the assEssment of Study qualiTy and reporting in EXercise (TESTEX scale).

RESULTS

Of the 27 reviewed studies, 15 reported positive effects on cognitive and motor-cognitive outcomes (i.e., performance improvements in measures of executive functions, working memory, and choice stepping reaction test), and a considerable heterogeneity concerning study-related, population-related, and intervention-related characteristics was noticed. A more detailed analysis suggests that, in particular, interventions using online classes and technology-based exercise devices (i.e., step-based exergames) can improve cognitive performance in healthy older adults. Approximately one-half of the reviewed studies were rated as having a high risk of bias with respect to completion adherence (≤85%) and monitoring of the level of regular physical activity in the control group.

CONCLUSION

The current state of evidence concerning the effectiveness of digital and home-based physical training interventions is mixed overall, though there is limited evidence that specific types of digital and home-based physical training interventions (e.g., online classes and step-based exergames) can be an effective strategy for improving cognitive performance in older adults. However, due to the limited number of available studies, future high-quality studies are needed to buttress this assumption empirically and to allow for more solid and nuanced conclusions.

Relationships between physical activity, sleep, and screen time with academic performance and psychological functioning among US children and adolescents with depression

OBJECTIVE

This cross-sectional study examined the relationships between adherence to 24-HMB guidelines (including physical activity [PA], screen time [ST], and sleep) with academic performance and psychological functioning among children and adolescents with depression.

METHODS

This study consists of 2165 participants aged 6-17 years with depression. Independent variables were components of 24-HMB guideline adherence, while outcomes of interest were academic performance (i.e., caring about school performance and completion of required homework) and psychological functioning (i.e., resilience and self-regulation). Logistic regression analysis was conducted while adjusting for confounding variables.

RESULTS

Only 1.03 % of the participants adhered to PA + ST + Sleep guidelines. Compared to non-adherence, adherence to PA + ST guidelines was significantly linked to a greater likelihood of caring about school performance (OR = 2.17), while ST + Sleep guidelines adherence was significantly linked to a greater likelihood of caring about school performance (OR = 2.02), completing homework (OR = 2.91), resilience (OR = 2.51), and self-regulation (OR = 2.51). Furthermore, adherence to PA + ST + Sleep guidelines was significantly linked to a higher likelihood of caring about school performance (OR = 5.01), resilience (OR = 2.49), and self-regulation (OR = 2.88) among these participants with depression.

CONCLUSION

Adhering to 24-HMB guidelines is positively linked to academic performance and psychological functioning among children and adolescents with depression. Thus, establishing healthy lifestyle behaviors should be promoted in school settings.

Relationship between self-reported sleep and cognitive function: a specification curve analysis

The relationship between self-reported sleep and cognitive function is complex; it is unclear whether self-reported sleep is a robust correlate of people's cognitive function. We address this gap by using a comprehensive large-scale dataset (N = 1054) coupled with a novel modeling approach, specification curve analysis (SCA), to test the association between self-reported sleep and cognitive function. The results of the SCA showed robust correlations between self-reported sleep and cognitive function, with poorer sleep associated with worse cognitive function. Furthermore, the correlations between sleep components and cognitive function were heterogeneous, with differences emerging across cognitive measures and domains. Specifically, daytime dysfunction was associated with the strongest effect on subjective cognitive function, whereas sleep duration and sleep efficiency had the strongest effect on objective cognitive function. Therefore, the relationship between self-reported sleep and cognition depends largely on what and how cognitive function is measured. Our findings guide measurement and domain selection for future research on the role of sleep in cognitive function.

Potential pathways of association from green space to smartphone addiction

Green space is increasingly known to improve physical and mental health. Based on these benefits, green space might also be expected to help mitigate related harmful behavioral patterns, such as obsessive Internet use and relevant addictions. In response, we conducted a study on smartphone addiction, a new form of Internet addiction. We carried out a cross-sectional investigation in August 2022. We recruited 1011 smartphone users across China, measured the Normalized Difference Vegetation Index (NDVI) in their residential neighborhoods (in 1, 2, and 3 km buffers), and captured data on smartphone addiction via the Smartphone Addiction Scale - Short version (SAS-SV). Potential mediators between green space and smartphone addiction, including physical activity, stress, and loneliness, were also reported by participants using the Physical Activity Rating Scale-3 (PRS-3), Depression, Anxiety and Stress Scale-21 Items (DASS-21), and 8-items UCLA Loneliness Scale scales (ULS-8). Multiple linear regression was employed to examine the relationships between green space and smartphone addiction. Structural equation modeling was performed to examine the potential pathways between these variables. Unexpectedly, NDVI in 1 km buffers was positively associated with smartphone addiction. By contrast, population density, an indicator of urbanization, was associated with lower levels of smartphone addiction levels in all NDVI buffer sizes. Meanwhile, we found NDVI was strongly associated with population density as well as other indicators of urbanization. Generally, our findings are unexpected and suggest that greenness may serve as an indicator of urbanization at national levels and that urbanization may buffer against smartphone addiction. During the hot summer, green space and indoor facilities may have competitive land uses, so future research should examine whether this association exists in other seasons and scenarios. We also recommend alternative models to systematically evaluate the effects of different components of residential environments.

Intertemporal Decision-making and Risk Decision-making Among Habitual Nappers Under Nap Sleep Restriction: A Study from ERP and Time-frequency

Sleep restriction affects people's decision-making behavior. Nap restriction is a vital subtopic within sleep restriction research. In this study, we used EEG to investigate the impact of nap sleep restriction on intertemporal decision-making (Study 1) and decision-making across risky outcomes (Study 2) from ERP and time-frequency perspectives. Study 1 found that habitual nappers restricting their naps felt more inclined to choose immediate, small rewards over delayed, large rewards in an intertemporal decision-making task. P200s, P300s, and LPP in our nap-restriction group were significantly higher than those in the normal nap group. Time-frequency results showed that the delta band (1 ~ 4 Hz) power of the restricted nap group was significantly higher than that of the normal nap group. In Study 2, the nap-restriction group was more likely to choose risky options. P200s, N2s, and P300s in the nap deprivation group were significantly higher than in the normal nap group. Time-frequency results also found that the beta band (11 ~ 15 Hz) power of the restricted nap group was significantly lower than that of the normal nap group. The habitual nappers became more impulsive after nap restriction and evinced altered perceptions of time. The time cost of the LL (larger-later) option was perceived to be too high when making intertemporal decisions, and their expectation of reward heightened when making risky decisions-believing that they had a higher probability of receiving a reward. This study provided electrophysiological evidence for the dynamic processing of intertemporal decision-making, risky decision-making, and the characteristics of nerve concussions for habitual nappers.

Physically active undergraduates perform better on executive-related oculomotor control: Evidence from the antisaccade task and pupillometry

Previous studies have shown that exercise can improve executive function in young and older adults. However, it remains controversial whether a sufficient amount of physical activity leads to higher-level executive function. To examine the effect of physical activity on executive function, we used eye-tracking technology and the antisaccade task in 41 young undergraduates with various levels of physical activity. Moreover, we also investigated their differences in cognitive ability by examining their pupil size during the antisaccade task. Eye-tracking results showed that physically active individuals showed shorter saccade latency and higher accuracy in the antisaccade task than their physically inactive counterparts. Furthermore, the former showed larger pupil size during the preparatory period of antisaccade. These findings suggest that individuals with higher-level physical activity have higher-level executive function. The larger pupil sizes of physically active individuals may imply that their locus coeruleus-norepinephrine system and executive-related prefrontal cortex are more active, which contributes to their higher-level cognitive ability.

The relationship between health belief and sleep quality of Chinese college students: The mediating role of physical activity and moderating effect of mobile phone addiction

Background

Poor sleep quality has become a common health problem encountered by college students.

Methods

Health belief scale (HBS), physical activity rating scale (PARS-3), mobile phone addiction tendency scale (MPATS) and Pittsburgh sleep quality index (PSQI) were adopted to analyze the data collected from survey questionnaires, which were filled out by 1,019 college students (including 429 males and 590 females) from five comprehensive colleges and universities from March 2022 to April 2022. The data collected from survey questionnaires were analyzed using SPSS and its macro-program PROCESS.

Results

(1) Health belief, physical activity, mobile phone addiction and sleep quality are significantly associated with each other (P < 0.01); (2) physical activity plays a mediating role between health belief and sleep quality, and the mediating effects account for 14.77%; (3) mobile phone addiction can significantly moderate the effect size of health belief (β = 0.062, p < 0.05) and physical activity (β = 0.073, P < 0.05) on sleep quality, and significantly moderate the effect size of health belief on physical activity (β = -0.112, p < 0.001).

Conclusion

The health belief of college students can significantly improve their sleep quality; college students' health belief can not only improve their sleep quality directly, but also improve their sleep quality through physical activity; mobile phone addiction can significantly moderate the effect size of health belief on sleep quality, the effect size of health belief on physical activity, and the effect size of physical activity on sleep quality.

Time-restricted feeding and cognitive function in sedentary and physically active elderly individuals: Ramadan diurnal intermittent fasting as a model

Objectives

This study aimed to investigate the effects of Ramadan diurnal intermittent fasting (RDIF) on cognitive performance, sleep quality, daytime sleepiness, and insomnia in physically active and sedentary elderly individuals.

Methods

A total of 58 participants (62.93 ± 3.99 years) were assigned to one of the following two groups: a sedentary group (control group) who observed Ramadan (n = 32) and a physically active group (n = 26) who continued to train while observing Ramadan. Participants were assessed 2 weeks before Ramadan and during the fourth week of Ramadan. On each occasion, participants completed a digital assessment of their cognitive performance and responded to the Pittsburgh sleep quality index (PSQI), the insomnia severity index (ISI) and the Epworth sleepiness scale (ESS) questionnaires to assess sleep parameters.

Results

Compared to before Ramadan, performance in executive function (p = 0.035), attention (p = 0.005), inhibition (p = 0.02), associative memory (p = 0.041), and recognition memory (p = 0.025) increased significantly during Ramadan in the physically active group. For the sedentary group, associative learning performance decreased (p = 0.041), whilst performances in the remaining domains remained unchanged during Ramadan. Global PSQI, ISI, and ESS scores indicated both groups suffered from poor sleep quality and excessive daytime sleepiness, with significantly higher negative effects of RDIF observed in the sedentary group.

Conclusion

Older adults who continue to train at least three times per week during Ramadan may improve their cognitive performance, despite the impairment of sleep quality. Future studies in older adults during Ramadan including objective measures of sleep (e.g., polysomnography, actigraphy) and brain function (e.g., functional magnetic resonance imaging) are warranted.

The Associations between Daytime Physical Activity, While-in-Bed Smartphone Use, Sleep Delay, and Sleep Quality: A 24-h Investigation among Chinese College Students

Bedtime smartphone use is an emerging issue that threatens the sleep health of children and young adults. Physical activity can have numerous health benefits, including reducing problematic or addictive behavior. However, the role of daily physical activity in reducing bedtime smartphone use is understudied. Hence, we conducted a one-day cross-sectional on the weekend (21-22 May 2021) to investigate the associations between daytime physical activity, bedtime smartphone use, and sleep quality. A total of 828 college students were recruited in two colleges. Their daytime physical activity indices were captured, including self-reported physical activity duration, intensity, volume, and smartphone-monitored walking steps. The participants reported whether they used smartphone while lying in bed (before sleep) and whether they delayed sleep due to smartphone use. Their while-in-bed screen time (duration) and subsequent sleep quality were also measured with self-report and a numeric rating scale, respectively. The results suggested that daytime physical activity duration was associated with lower chances of while-in-bed smartphone use (OR = 0.907, p = 0.019) and smartphone-related sleep delay (OR = 0.932, p = 0.014). However, no significant association was found between physical activity indices and while-in-bed screen time or sleep quality. These findings may contribute to understanding the reciprocal relationship between physical activity and smartphone use and highlighting the potential of controlling problematic bedtime smartphone use through daily physical activity. Future research is warranted to examine the associations with extra objective measures.

Better Subjective Sleep Quality Partly Explains the Association Between Self-Reported Physical Activity and Better Cognitive Function

Background: Physical activity has been associated with better cognitive function and better sleep quality. Yet, whether the beneficial effect of physical activity on cognitive function can be explained by an indirect pathway involving better sleep quality is unclear. Objective: To investigate whether sleep quality mediates the association between physical activity and cognitive function in adults 50 years of age or older. Methods: 86,541 community-dwelling European adults were included in the study. Physical activity and sleep quality were self-reported. Indicators of cognitive function (immediate recall, delayed recall, verbal fluency) were assessed using objective tests. All measures were collected six times between 2004 and 2017. The mediation was tested using multilevel mediation analyses. Results: Results showed that self-reported physical activity was associated with better self-reported sleep quality, which was associated with better performance in all three indicators of cognitive function, demonstrating an indirect effect of physical activity on cognitive function through sleep quality. The mediating effect of sleep quality accounted for 0.41%, 1.46%, and 8.88% of the total association of physical activity with verbal fluency, immediate recall, and delayed recall, respectively. Conclusion: These findings suggest that self-reported sleep quality partly mediates the association between self-reported physical activity and cognitive function. These results need to be confirmed by device-based data of physical activity and sleep quality.

The Influence of Acute Sprint Interval Training on Cognitive Performance of Healthy Younger Adults

There is considerable evidence showing that an acute bout of physical exercises can improve cognitive performance, but the optimal exercise characteristics (e.g., exercise type and exercise intensity) remain elusive. In this regard, there is a gap in the literature to which extent sprint interval training (SIT) can enhance cognitive performance. Thus, this study aimed to investigate the effect of a time-efficient SIT, termed as "shortened-sprint reduced-exertion high-intensity interval training" (SSREHIT), on cognitive performance. Nineteen healthy adults aged 20-28 years were enrolled and assessed for attentional performance (via the d2 test), working memory performance (via Digit Span Forward/Backward), and peripheral blood lactate concentration immediately before and 10 min after an SSREHIT and a cognitive engagement control condition (i.e., reading). We observed that SSREHIT can enhance specific aspects of attentional performance, as it improved the percent error rate (F%) in the d-2 test (t (18) = -2.249, p = 0.037, d = -0.516), which constitutes a qualitative measure of precision and thoroughness. However, SSREHIT did not change other measures of attentional or working memory performance. In addition, we observed that the exercise-induced increase in the peripheral blood lactate levels correlated with changes in attentional performance, i.e., the total number of responses (GZ) (rm = 0.70, p < 0.001), objective measures of concentration (SKL) (rm = 0.73, p < 0.001), and F% (rm = -0.54, p = 0.015). The present study provides initial evidence that a single bout of SSREHIT can improve specific aspects of attentional performance and conforming evidence for a positive link between cognitive improvements and changes in peripheral blood lactate levels.

Higher Handgrip Strength Is Linked to Better Cognitive Performance in Chinese Adults with Hypertension

Objective: There is growing evidence that in adults, higher levels of handgrip strength (HGS) are linked to better cognitive performance. However, the relationship between HGS and cognitive performance has not been sufficiently investigated in special cohorts, such as individuals with hypertension who have an intrinsically higher risk of cognitive decline. Thus, the purpose of this study was to examine the relationship between HGS and cognitive performance in adults with hypertension using data from the Global Ageing and Adult Health Survey (SAGE). Methods: A total of 4486 Chinese adults with hypertension from the SAGE were included in this study. Absolute handgrip strength (aHGS in kilograms) was measured using a handheld electronic dynamometer, and cognitive performance was assessed in the domains of short-term memory, delayed memory, and language ability. Multiple linear regression models were fitted to examine the association between relative handgrip strength (rHGS; aHGS divided by body mass index) and measures of cognitive performance. Results: Overall, higher levels of rHGS were associated with higher scores in short-term memory (β = 0.20) and language (β = 0.63) compared with the lowest tertiles of rHGS. In male participants, higher HGS was associated with higher scores in short-term memory (β = 0.31), language (β = 0.64), and delayed memory (β = 0.22). There were no associations between rHGS and cognitive performance measures in females. Conclusion: We observed that a higher level of rHGS was associated with better cognitive performance among hypertensive male individuals. Further studies are needed to investigate the neurobiological mechanisms, including sex-specific differences driving the relationship between measures of HGS and cognitive performance in individuals with hypertension.