Sleep and physical activity - the dynamics of bi-directional influences over a fortnight

Physical and psychological status of emergency assistance personnel at major public health events: a qualitative descriptive study

BACKGROUND

Many personnel respond to natural disasters like earthquakes and tsunamis and frequent public health events like Ebola and COVID-19. However, research on emergency assistance personnel remains limited. This study aims to describe the perceived well-being among responders deployed in isolated or emergency international missions while providing practical references to intervene in developing similar missions.

METHODS

For this qualitative phenomenological study, purposive sampling was used following the principle of maximum differentiation to select personnel deployed on an emergency mission for over a year. Data collection continued until data saturation. Phenomenologically semi-structured interviews helped explore the physical and psychological status of the participants with Colaizzi's method.

RESULTS

Eleven personnel were interviewed after the mission, with four major themes being identified: 'perceived somatic change,' 'perceived emotional change,' 'behavioral change,' and 'coping with perceived change.'

CONCLUSIONS

The mental health status of the emergency assistance personnel was affected by multiple factors from external and internal environments. The current study explored the physical and psychological feelings and emotions of emergency assistance personnel during an emergency mission. The study provided a practical reference for health management under similar missions.

REGISTRATIONS

Not registered.

Association of Abnormal Sleep Duration and Sleep Disturbance with Physical Activity in Older Adults: Between- and within-Person Effects

OBJECTIVES

Sleep is associated with physical activity (PA), yet the nature and directions of this association are less understood. This study aimed to disentangle the long-term temporal sequences between sleep duration/disturbance and PA in older adults, distinguishing between- and within-person effects.

DESIGN

Longitudinal panel study.

SETTING AND PARTICIPANTS

We conducted a longitudinal study using 3 waves of data collected in 2008/09 (T1), 2012/13 (T2), and 2016/17(T3) from adults aged ≥50 years in the English Longitudinal Study of Ageing (N = 10,749 individuals).

MEASURES

Sleep duration, sleep disturbance, and PA were assessed by self-reported questionnaires. We used cross-lagged panel models (CLPMs) to examine between-person effects and random intercept cross-lagged panel models (RI-CLPMs) to examine within-person effects.

RESULTS

Our analyses revealed a reciprocal relationship between abnormal sleep duration and low PA levels at between-person level (abnormal sleep duration to PA: βT1-T2 = -0.053, βT2-T3 = -0.058, all P < .001; PA to abnormal sleep duration: βT1-T2 = -0.040, βT2-T3 = -0.045, all P < .05), with abnormal sleep duration being the driving force in the dynamic association. In addition, there was a unidirectional effect of more severe sleep disturbance on lower levels of PA at both between- and within-person levels (between-person level: βT1-T2 = -0.032, βT2-T3 = -0.028, all P < .001; within-person level: βT1-T2 and T2-T3 = -0.031, all P = .011).

CONCLUSIONS AND IMPLICATIONS

This study adds novel insights into the temporal directionality of sleep and PA among community-dwelling older adults and highlights poor sleep as a potential risk factor for PA. Intervention strategies should aim to improve sleep to promote PA levels and successful aging.

Sleep duration and cardiorespiratory fitness in adolescents: Longitudinal analysis from the LabMed study

PURPOSE

We aimed to investigate longitudinal associations between sleep duration and cardiorespiratory fitness, in adolescents.

METHODS

Sleep duration was self-reported and cardiorespiratory fitness was assessed by the 20 m shuttle run test, both at baseline and follow-up (2-year follow-up). Participants were 734 Northern Portuguese adolescents (349 girls), aged 14.6 ± 1.8 years, from the LabMed study.

RESULTS

Significant decreases were found between baseline and follow-up for sleep duration, whereas for cardiorespiratory fitness there was an increase. Adolescents with short sleep duration at baseline had lower cardiorespiratory fitness at follow-up, comparing to those meeting the sleep guidelines (odds ratio [OR] = 0.506, 95% confidence interval [CI]: 0.326-0.785; p = .002 for whole week; OR = 0.597, 95% CI: 0.407-0.875; p = .008 for weekdays). Girls who were short sleepers at baseline had lower odds of having a healthy cardiorespiratory fitness at follow-up, comparing to those meeting the sleep guidelines (OR = 0.311, 95% CI: 0.158-0.613; p < .001 for whole week; OR = 0.469, 95% CI: 0.262-0.838; p = .011 for weekdays). No significant associations between sleep duration and cardiorespiratory fitness were found for boys.

DISCUSSION

There was a significant longitudinal association between short sleep duration and lower cardiorespiratory fitness levels, particularly in girls. Future interventions targeting adolescents' sleep duration should acknowledge behavioral differences between genders, as well as different behaviors adopted by boys ang girls, specifically on weekends.

Temporal Interactions between Maintenance of Cerebral Cortex Thickness and Physical Activity from an Individual Person Micro-Longitudinal Perspective and Implications for Precision Medicine

Maintenance of brain structure is essential for neurocognitive health. Precision medicine has interests in understanding how maintenance of an individual person's brain, including cerebral cortical structure, interacts with lifestyle factors like physical activity. Cortical structure, including cortical thickness, has recognized relationships with physical activity, but concepts of these relationships come from group, not individual, focused findings. Whether or how group-focused concepts apply to an individual person is fundamental to precision medicine interests but remains unclear. This issue was studied in a healthy man using concurrent micro-longitudinal tracking of magnetic resonance imaging-defined cortical thickness and accelerometer-defined steps/day over six months. These data permitted detailed examination of temporal relationships between thickness maintenance and physical activity at an individual level. Regression analyses revealed graded significant and trend-level temporal interactions between preceding activity vs. subsequent thickness maintenance and between preceding thickness maintenance vs. subsequent activity. Interactions were bidirectional, delayed/prolonged over days/weeks, positive, bilateral, directionally asymmetric, and limited in strength. These novel individual-focused findings in some ways are predicted, but in other ways remain unaddressed or undetected, by group-focused work. We suggest that individual-focused concepts of temporal interactions between maintenance of cortical structure and activity can provide needed new insight for personalized tailoring of physical activity, cortical, and neurocognitive health.

Associations of daily sedentary behavior, physical activity, and sleep with irritable bowel syndrome: A prospective analysis of 362,193 participants

BACKGROUND

Irritable bowel syndrome (IBS) substantially affects quality of life and requires early prevention. This study aimed to elucidate the relationships between IBS and daily behaviors, including sedentary behavior (SB), physical activity (PA), and sleep. In particular, it seeks to identify healthy behaviors to reduce IBS risk, which previous studies have rarely addressed.

METHODS

Daily behaviors were retrieved from self-reported data of 362,193 eligible UK Biobank participants. Incident cases were determined by self-report or health care data according to Rome IV criteria.

RESULTS

A total of 345,388 participants were IBS-free at baseline, during a median follow-up of 8.45 years, 19,885 incident IBS cases were recorded. When examined individually, SB and shorter (≤7 h/day) or longer (>7 h/day) sleep duration were each positively associated with increased IBS risk, and PA was associated with lower IBS risk. The isotemporal substitution model suggested that replacing SB with other activities could provide further protective effects against IBS risk. Among people sleeping ≤7 h/day, replacing 1 h of SB with equivalent light PA, vigorous PA, or sleep was associated with 8.1% (95% confidence interval (95%CI): 0.901-0.937), 5.8% (95%CI: 0.896-0.991), and 9.2% (95%CI: 0.885-0.932) reduced IBS risk, respectively. For people sleeping >7 h/day, light and vigorous PA were associated with a 4.8% (95%CI: 0.926-0.978) and a 12.0% (95%CI: 0.815-0.949) lower IBS risk, respectively. These benefits were mostly independent of genetic risk for IBS.

CONCLUSION

SB and unhealthy sleep duration are risk factors for IBS. A promising way to mitigate IBS risk for individuals sleeping ≤7 h/day and for those sleeping >7 h/day appears to be by replacing SB with adequate sleep or vigorous PA, respectively, regardless of the genetic predisposition of IBS.

Lifestyle Variation among the Elderly: Do Nutritional Knowledge and Diet Quality Differ When the Other Lifestyle Components Are Similar?

Older people's health is strongly determined by their lifestyle, and its deterioration is a cause for concern and calls for effective efforts to slow down the process. The aim of the study was to determine the relationship between diet quality and other non-food lifestyle elements. The data were collected in 2017 through a cross-sectional survey among 271 Polish elder citizens. A K-means cluster analysis was applied to separate homogeneous groups by lifestyle components (without diet) and a logistic regression was used to analyze the relationships between identified clusters and sociodemographic characteristics, nutritional knowledge and diet quality. Three homogenous clusters were identified, i.e., individuals with moderate physical activity and recommended sleep duration (pro-healthy), with low physical activity (low PA), and with short sleep (short sleep). Gender, age, education, place of residence, BMI, and health-promoting diet index (pHDI) did not differentiate adherence to clusters. The probability of being in the pro-healthy cluster increased with nutritional knowledge and declaring the same or better health status compared to peers, while it decreased when above-average financial status was reported. The obtained results importantly extend the previous findings by showing that the individual elements of lifestyle should be also perceived in the context of others. Further research focused on lifestyle as a whole might considerably support the implementation of multifaceted lifestyle interventions.

The Relationships between Various Factors and Sleep Status: A Cross-Sectional Study among Healthy Saudi Adults

Impaired sleep can adversely affect daily life. This study assesses the association between different factors and sleep status among apparently healthy Saudi adults. In total, 478 adults were included in this study. Data on anthropometrics, body composition, stress scales, physical activity, and dietary habits were collected. Fasting blood glucose and lipid profile were measured. Sleep quality and duration were assessed using the Pittsburgh Sleep Quality Index. Larger neck circumference (NC) was associated with short sleep duration (odds ratio (OR) 1.23; 95% confidence interval (CI) [1.08, 1.41]; p = 0.002). Higher triglyceride levels were associated with poor sleep quality (OR 1.01; 95% CI [1.002, 1.02]; p = 0.019) and short sleep duration (OR 1.01; 95% CI [1.004, 1.02]; p = 0.005). Stress was a risk factor for poor sleep quality (OR 1.15; 95% CI [1.09, 1.22]; p < 0.001). Being married was significantly associated with good sleep quality (OR 2.97; 95% CI [1.32, 6.71]; p = 0.009), while being single was correlated with longer sleep duration (OR 0.46; 95% CI [0.22, 0.96]; p = 0.039). Other factors such as having a larger waist circumference and more muscle mass were protective factors against poor sleep quality and/or short sleep duration. In conclusion, a larger NC is suggested as a risk factor for short sleep duration and a higher triglyceride level for both short and poor sleep among healthy Saudis. Investigating the factors associated with sleep status may help alleviate sleep disturbances and improve overall health. Further studies are needed to confirm causality using objective sleep measures.

Day-to-day directional relationships between sleep duration and negative affect

OBJECTIVE

There is a strong association between sleep disturbance and negative affect. However, the day-to-day directional connections between sleep and negative affect remain unclear. We examined day-to-day relationships between sleep duration and negative affect in community adults.

METHODS

Participants were two subsamples of the Midlife in the United States Study (Sample 1: n = 2,022; Sample 2: n = 782). Daily negative affect and previous night sleep duration were assessed via end-of-day telephone interviews for eight days. Random intercept cross-lagged panel models tested sleep duration as a predictor of next-day negative affect and vice versa, controlling for age, gender, and race.

RESULTS

In both samples, shorter sleep duration predicted higher next-day negative affect, but daily negative affect was not a significant predictor of upcoming-night sleep duration. Follow-up analyses indicated that the relationship between sleep duration and negative affect was nonlinear. Sleeping fewer than 7.5 hours or more than 10.5 hours was associated with greater next-day negative affect than sleeping between 7.5 and 10.5 hours.

CONCLUSIONS

In two large samples of community adults, sleep duration unidirectionally predicted higher next-day negative affect, and this relationship was nonlinear. Sleeping at least 7.5 hours and no more than 10.5 hours appeared to be an optimal range associated with lowest next-day negative affect.

Arterial stiffness and the reallocation of time between device-measured 24-hour movement behaviours: A compositional data analysis

BACKGROUND AND AIMS

Arterial stiffness predicts cardiovascular morbidity and mortality. We aimed to quantify the differences in arterial stiffness associated with reallocating time between 24-h movement behaviours.

METHODS

This observational cross-sectional study included Luxembourg residents aged 25-79y who each provided ≥4 valid days of triaxial accelerometry (n = 1001). Covariable adjusted compositional isotemporal substitution models were used to examine if theoretical reallocations of time between device-measured sedentariness, the sleep period, light physical activity (PA), and moderate-to-vigorous PA (MVPA) were associated with the percentage difference in carotid-femoral pulse wave velocity (cfPWV). We further investigated if replacing sedentary time accumulated in prolonged (≥30 min) with non-prolonged (<30 min) bouts was associated with arterial stiffness. The results are presented as 30 min time exchanges (β (95% confidence interval)).

RESULTS

Beneficial associations with lower cfPWV were observed when reallocating time to MVPA from the sleep period (-1.38 (-2.63 to -0.12) %), sedentary time (-1.70 (-2.76 to -0.62) %), and light PA (-2.51 (-4.55 to -0.43) %), respectively. Larger associations in the opposite direction were observed when reallocating MVPA to the same behaviours (for example, replacing MVPA with sedentary time: 2.50 (0.85-4.18) %). Replacing prolonged with non-prolonged sedentary time was not associated with cfPWV (-0.27 (-0.86 to 0.32) %). In short sleepers, reallocating sedentary time to the sleep period was favourable (-1.96 (-3.74 to -0.15) %).

CONCLUSIONS

Increasing or at least maintaining MVPA appears to be important for arterial health in adults. Extending sleep in habitually short sleepers, specifically by redistributing sedentary time, may also be important.

Physical activity, sleep and affective wellbeing on the following day: An experience sampling study

This study aims to investigate the temporal links between physical activity, sleep and affective wellbeing in young adults. In particular, the aim was to examine whether physical activity is associated with sleep indicators in subsequent nights and, in turn, whether sleep was associated with improved affective wellbeing the next morning. Relatedly, moderation by baseline levels of depressive symptoms, sleep quality, habitual physical activity and gender was analysed. One-hundred and forty-seven individuals (85.7% female) aged 18-25 years old participated in an experience sampling study over 14 consecutive days. Participants received seven prompts per day, and answered questions about their physical activity and affective states. Every morning, participants also reported their sleep. Physical activity throughout the day was not related to sleep during the following night or to affective wellbeing the next morning. An exception to that pattern was that physical activity before 14:00 hours was associated with longer subsequent sleep duration. Better subjective sleep quality predicted affective wellbeing the next morning. Associations of physical activity, sleep and affective wellbeing were not moderated by baseline depressive symptoms, sleep quality or habitual physical activity. However, investigation of gender as a moderator revealed that moderate physical activity was associated with better subsequent sleep quality for males, but not for females. Overall, we found that physical activity is associated with better subsequent sleep for males, but not for females. Also, our study provides further evidence that better sleep quality is associated with the next morning's affective wellbeing.

An examination of the reciprocal associations between physical activity and anxiety, depressive symptoms, and sleep quality during the first 9 weeks of the COVID-19 pandemic in Belgium

During the initial outbreak of the global COVID-19 pandemic, many countries imposed a total lockdown (containment at home). Although it was still allowed in Belgium to be physically active or exercise with people from your household in the vicinity of your home, engaging in sports or physical activity in a group or club context was no longer permitted. To examine whether a lack of physical activity was potentially threatening to the mental well-being of citizens and vice versa, the present study examined concurrent and reciprocal relationships between physical activity and anxiety, depressive symptoms, and sleep quality during the COVID-19 lockdown in a 9-week longitudinal design. In a sample of 983 Belgian adults (75.1% female; M _age = 43.78, range = 18-82 years), we explored these relationships at both the between- and within-person levels through random intercept cross-lagged panel models. The findings indicate that more physical activity was associated with lower symptoms of anxiety and depression and better sleep quality, a finding observed both at the between-person (across weeks; β_anxiety = -0.25, β_depression = -0.30, β_{sleep quality} = 0.24, p < .001) and within-person level (within weeks; β_anxiety = -0.10, β_depression = -0.14, β_{sleep quality} = 0.11, p < .05). Moreover, at the within-person level, an increase in feelings of anxiety and depression at one moment predicted lower levels of physical activity one week later (β_anxiety = -0.04, β_depression = -0.06, p < .05). Since poor mental health poses a threat to the maintenance of physical activity, the current findings suggest that it is critical to invest in the mental health of individuals during distressing times.

Endogenous circadian temperature rhythms relate to adolescents' daytime physical activity

Circadian rhythms relate to multiple aspects of health and wellbeing, including physical activity patterns. Susceptible circadian regulation predisposes to circadian misalignment, poor sleep, sleep deprivation, increased sleepiness, and thereby sedentary behavior. Adolescents' circadian regulation is particularly vulnerable, and may lead to sedentary behavior. To investigate which factors associate strongest between physical activity (PA) and circadian behavior, we conducted multimodal circadian rhythm analyses. We investigate how individual characteristics of habitual circadian patterns associate with objectively measured PA. We studied 312 adolescents [70% females) (56% with delayed sleep phase (DSP)], mean age 16.9 years. Circadian period length, temperature mesor (estimated 24 h midline) and amplitude (difference between mesor and peak) were measured using distally attached thermologgers (ibutton 1922L, 3-day-measurement). We additionally utilized algorithm-formed clusters of circadian rhythmicity. Sleep duration, timing, DSP, and PA were measured using actigraphs (GeneActiv Original, 10-day-measurement). We found that continuous circadian period length was not associated with PA, but lower mesor and higher amplitude were consistently associated with higher levels of PA as indicated by mean Metabolic Equivalent (METmean) and moderate-to-vigorous PA (MVPA), even when controlling for sleep duration. Separate circadian clusters formed by an algorithm also reflected distinct patterns of PA accordingly. Late sleepers and those with DSP were less likely to engage in MVPA compared to non-DSP and had more sedentary behavior. Adolescents who engage in higher levels or high-intensity PA have better circadian regulation, as measured by different objective methods including distal temperature measurements as well as actigraphy-measured sleep-wake behavior.