Socioeconomic gradients in 24-hour movement patterns across weekends and weekdays in a working-age sample: evidence from the 1970 British Cohort Study.

BACKGROUND: Socioeconomic differences in movement behaviours may contribute to health inequalities. The aim of this descriptive study was to investigate socioeconomic patterns in device-measured 24-hour movement and assess whether patterns differ between weekdays and weekends. METHODS: 4894 individuals aged 46 years from the 1970 British Cohort Study were included. Participants wore thigh-worn accelerometers for 7 days. Movement behaviours were classified in two 24-hour compositions based on intensity and posture, respectively: (1) sleep, sedentary behaviour, light-intensity activity and moderate-vigorous activity; and (2) sleep, lying, sitting, standing, light movement, walking and combined exercise-like activity. Four socioeconomic measures were explored: education, occupation, income and deprivation index. Movement behaviours were considered compositional means on a 24-hour scale; isometric log ratios expressed per cent differences in daily time in each activity compared with the sample mean. RESULTS: Associations were consistent across all socioeconomic measures. For example, those with a degree spent more time in exercise-like activities across weekdays (10.8%, 95% CI 7.3 to 14.7; ref: sample mean) and weekends (21.9%, 95% CI 17.2 to 26.9). Other patterns differed markedly by the day of the week. Those with no formal qualifications spent more time standing (5.1%, 95% CI 2.3 to 7.1), moving (10.8%, 95% CI 8.6 to 13.1) and walking(4.0%, 95% CI 2.2 to 6.1) during weekdays, with no differences on weekends. Conversely, those with no formal qualifications spent less time sitting during weekdays (-6.6%, 95% CI -7.8 to -4.8), yet more time lying on both weekends (8.8%, 95% CI 4.9 to 12.2) and weekdays (7.5%, 95% CI 4.0 to 11.5). CONCLUSIONS: There were strong socioeconomic gradients in 24-hour movement behaviours, with notable differences between weekdays/weekends and behaviour type/posture. These findings emphasise the need to consider socioeconomic position, behaviour type/posture and the day of the week when researching or designing interventions targeting working-age adults.

A narrative review of global and national physical activity and sedentary behaviour guidelines development processes - The GUidelines Standards (GUS) project.

BACKGROUND: Clinical and public health guidelines serve to direct clinical practice and policy, based on the best available evidence. The World Health Organization (WHO) and national health bodies of many countries have released physical activity and sedentary behaviour guidelines. Despite significant overlap in the body of evidence reviewed, the guidelines differ across jurisdictions. This study aimed to review the processes used to develop global and national physical activity and sedentary behaviour guidelines and examine the extent to which they conform with a recommended methodological standard for the development of guidelines. METHODS: We extracted data on nine sets of guidelines from seven jurisdictions (WHO, Australia, Canada, Japan, the Netherlands, United Kingdom, and United States). We rated each set of guidelines as high, medium, or low quality on criteria related to the rigour of the development process. RESULTS: We observed variation in the quality of guidelines development processes across jurisdictions and across different criteria. Guidelines received the strongest overall ratings for criteria on clearly describing the evidence selected and stating an explicit link between the recommendations and the supporting evidence. Guidelines received the weakest overall ratings for criteria related to clearly describing the methods used to formulate the recommendations and reporting external review by experts prior to publication. Evaluated against the selected criteria, the strongest processes were undertaken by the WHO and Canada. CONCLUSIONS: Reaching agreement on acceptable guideline development processes, as well as the inclusion and appraisal procedures of different types of evidence, would help to strengthen and align future guidelines.

Timing of Moderate to Vigorous Physical Activity, Mortality, Cardiovascular Disease, and Microvascular Disease in Adults With Obesity.

OBJECTIVE: To assess the association between timing of aerobic moderate to vigorous physical activity (MVPA) and risk of cardiovascular disease (CVD), microvascular disease (MVD), and all-cause mortality in adults with obesity and a subset with obesity and type 2 diabetes (T2D). RESEARCH DESIGN AND METHODS: Participants included adults with obesity (BMI ≥30 kg/m2) and a subset of those with T2D from the UK Biobank accelerometry substudy. Aerobic MVPA was defined as bouts of MVPA lasting ≥3 continuous minutes. Participants were categorized into morning, afternoon, or evening MVPA based on when they undertook the majority of their aerobic MVPA. The reference group included participants with an average of less than one aerobic MVPA bout per day. Analyses were adjusted for established and potential confounders. RESULTS: The core sample included 29,836 adults with obesity, with a mean age of 62.2 (SD 7.7) years. Over a mean follow-up period of 7.9 (SD 0.8) years, 1,425 deaths, 3,980 CVD events, and 2,162 MVD events occurred. Compared with activity in the reference group, evening MVPA was associated with the lowest risk of mortality (hazard ratio [HR] 0.39; 95% CI 0.27, 0.55), whereas afternoon (HR 0.60; 95% CI 0.51, 0.71) and morning MVPA (HR 0.67; 95% CI 0.56, 0.79) demonstrated significant but weaker associations. Similar patterns were observed for CVD and MVD incidence, with evening MVPA associated with the lowest risk of CVD (HR 0.64; 95% CI 0.54, 0.75) and MVD (HR 0.76; 95% CI 0.63, 0.92). Findings were similar in the T2D subset (n = 2,995). CONCLUSIONS: Aerobic MVPA bouts undertaken in the evening were associated with the lowest risk of mortality, CVD, and MVD. Timing of physical activity may play a role in the future of obesity and T2D management.

Is dog walking suitable for physical activity promotion? Investigating the exercise intensity of on-leash dog walking.

Background: Approximately a quarter of the global population is physically inactive, increasing the prevalence of chronic health conditions such as cardiovascular disease. Clearly, a population shift is needed to increase physical activity participation. Given almost half of American and Australian households have at least one dog, dog walking has the potential to increase physical activity. The objective of this study was to characterize the exercise intensity of dog walking using physiological measures to determine whether it achieved a threshold for health-enhancement. Method: From February 2020 to September 2022, dog owners (aged > 18 years, without impediment to walking) who resided in metropolitan Sydney participated in an on-leash dog walk for a minimum of 20 minutes, while wearing a heart rate monitor and carrying a phone to track cadence, route and duration. Results: Forty-three participants were recruited (aged 34.26 ± 16 years). Data from measures of %heart rate reserve (38 ± 10.8 %HRR), %heart rate max (61 ± 7.2 %HRmax) and average cadence (45 ± 8.4steps/min) classified dog-walking as light intensity. However, when using average walking speed (4.29 ± 0.8 km/hr) and metabolic equivalents (3.53 ± 0.6METs), the walk was classified as moderate intensity. Conclusion: Overall, depending on the intensity measure used, dog walking was positioned in the upper range of light intensity and the lower range of moderate intensity. Although dog walking at a certain intensity may be difficult to prescribe as strategy for meeting current moderate-to-vigorous focused physical activity recommendations, it should be recognised as a beneficial activity that may reach moderate intensity on some occasions.

Occupational physical activity, all-cause, cardiovascular disease, and cancer mortality in 349,248 adults: Prospective and longitudinal analyses of the MJ Cohort.

BACKGROUND: Evidence on the health benefits of occupational physical activity (OPA) is inconclusive. We examined the associations of baseline OPA and OPA changes with all-cause, cardiovascular disease (CVD), and cancer mortality and survival times. METHODS: This study included prospective and longitudinal data from the MJ Cohort, comprising adults over 18 years recruited in 1998-2016. 349,248 adults (177,314 women) with baseline OPA, of whom 105,715 (52,503 women) had 2 OPA measures at 6.3 ± 4.2 (mean ± SD) years apart. Exposures were baseline OPA, OPA changes, and baseline leisure-time physical activity. RESULTS: Over a mean mortality follow-up of 16.2 ± 5.5 years for men and 16.4 ± 5.4 years for women, 11,696 deaths (2033 of CVD and 4631 of cancer causes) in men and 8980 deaths (1475 of CVD and 3689 of cancer causes) in women occurred. Combined moderately heavy/heavy baseline OPA was beneficially associated with all-cause mortality in men (multivariable-adjusted hazard ratio (HR) = 0.93, 95% confidence interval (95%CI): 0.89-0.98 compared to light OPA) and women (HR = 0.86, 95%CI: 0.79-0.93). Over a mean mortality follow-up of 12.5 ± 4.6 years for men and 12.6 ± 4.6 years for women, OPA decreases in men were detrimentally associated (HR = 1.16, 95%CI: 1.01-1.33) with all-cause mortality, while OPA increases in women were beneficially (HR = 0.83, 95%CI: 0.70-0.97) associated with the same outcome. Baseline or changes in OPA showed no associations with CVD or cancer mortality. CONCLUSION: Higher baseline OPA was beneficially associated with all-cause mortality risk in both men and women. Our longitudinal OPA analyses partly confirmed the prospective findings, with some discordance between sex groups.

Relationship of device measured physical activity type and posture with cardiometabolic health markers: pooled dose-response associations from the Prospective Physical Activity, Sitting and Sleep Consortium.

AIMS/HYPOTHESIS: The aim of this study was to examine the dose-response associations of device-measured physical activity types and postures (sitting and standing time) with cardiometabolic health. METHODS: We conducted an individual participant harmonised meta-analysis of 12,095 adults (mean ± SD age 54.5±9.6 years; female participants 54.8%) from six cohorts with thigh-worn accelerometry data from the Prospective Physical Activity, Sitting and Sleep (ProPASS) Consortium. Associations of daily walking, stair climbing, running, standing and sitting time with a composite cardiometabolic health score (based on standardised z scores) and individual cardiometabolic markers (BMI, waist circumference, triglycerides, HDL-cholesterol, HbA1c and total cholesterol) were examined cross-sectionally using generalised linear modelling and cubic splines. RESULTS: We observed more favourable composite cardiometabolic health (i.e. z score <0) with approximately 64 min/day walking (z score [95% CI] -0.14 [-0.25, -0.02]) and 5 min/day stair climbing (-0.14 [-0.24, -0.03]). We observed an equivalent magnitude of association at 2.6 h/day standing. Any amount of running was associated with better composite cardiometabolic health. We did not observe an upper limit to the magnitude of the dose-response associations for any activity type or standing. There was an inverse dose-response association between sitting time and composite cardiometabolic health that became markedly less favourable when daily durations exceeded 12.1 h/day. Associations for sitting time were no longer significant after excluding participants with prevalent CVD or medication use. The dose-response pattern was generally consistent between activity and posture types and individual cardiometabolic health markers. CONCLUSIONS/INTERPRETATION: In this first activity type-specific analysis of device-based physical activity, ~64 min/day of walking and ~5.0 min/day of stair climbing were associated with a favourable cardiometabolic risk profile. The deleterious associations of sitting time were fully attenuated after exclusion of participants with prevalent CVD and medication use. Our findings on cardiometabolic health and durations of different activities of daily living and posture may guide future interventions involving lifestyle modification.

Health coaching intervention with or without the support of an exercise buddy to increase physical activity of people with chronic low back pain compared to usual care: a feasibility and pilot randomised controlled trial.

BACKGROUND: Exercise buddies (people to exercise together with) might support people with low back pain (LBP) to become active. However, involving buddies in randomised controlled trials (RCT) might challenge recruitment, data collection and follow-up. OBJECTIVES: To explore the feasibility of the intervention, recruitment and data collection approaches and potential effects of a health coaching intervention (focused on physical activity) with or without exercise buddies' support on physical activity of people with chronic LBP versus usual discharge care. DESIGN: Feasibility and pilot RCT. METHODS: Adults (n = 30) discharged from LBP treatment were randomised to the Buddy-Assisted (health coaching intervention with exercise buddy's support), Individual-Only (health coaching only), or usual care groups. Data were collected at baseline, three and six months. The feasibility of trial's procedures was assessed through recruitment rate (acceptable if >70%), data completion rate (acceptable if ≤ 20% missing data), and follow-up rate (successful if ≥ 85%). The intervention's acceptability was assessed via feedback questionnaires. Preliminary effects on physical activity and other outcomes were also explored. RESULTS: Recruitment and baseline data completion were acceptable. However, data collection and follow-up rates post-randomisation were not. 85% of the Buddy-Assisted Group believed the buddies helped them to increase physical activity and would recommend the intervention. 70% of the Individual-Only and Control groups believed exercise buddies would help them to become further active. CONCLUSION: The data collection and follow-up approaches were not successful and need amending before a large-scale RCT. Nonetheless, the buddy-assisted intervention was well-accepted. A future RCT will focus on differences in clinical outcomes. TRIAL REGISTRATION: The study was registered at the Australian New Zealand Clinical Trial Registry (ACTRN12620001118998).

Structural disconnectivity in postoperative delirium: A perioperative two-center cohort study in older patients.

BACKGROUND: Structural disconnectivity was found to precede dementia. Global white matter abnormalities might also be associated with postoperative delirium (POD). METHODS: We recruited older patients (≥65 years) without dementia that were scheduled for major surgery. Diffusion kurtosis imaging metrics were obtained preoperatively, after 3 and 12 months postoperatively. We calculated fractional anisotropy (FA), mean diffusivity (MD), mean kurtosis (MK), and free water (FW). A structured and validated delirium assessment was performed twice daily. RESULTS: Of 325 patients, 53 patients developed POD (16.3%). Preoperative global MD (standardized beta 0.27 [95% confidence interval [CI] 0.21-0.32] p < 0.001) was higher in patients with POD. Preoperative global MK (-0.07 [95% CI -0.11 to (-0.04)] p < 0.001) and FA (0.07 [95% CI -0.10 to (-0.04)] p < 0.001) were lower. When correcting for baseline diffusion, postoperative MD was lower after 3 months (0.05 [95% CI -0.08 to (-0.03)] p < 0.001; n = 183) and higher after 12 months (0.28 [95% CI 0.20-0.35] p < 0.001; n = 45) among patients with POD. DISCUSSION: Preoperative structural disconnectivity was associated with POD. POD might lead to white matter depletion 3 and 12 months after surgery.

Joint Associations of Diet and Device-measured Physical Activity with Mortality and Incident CVD and Cancer: a prospective analysis of the UK Biobank Study.

BACKGROUND: We examined the joint associations of diet and device-measured intensity-specific PA with all-cause mortality (ACM), cardiovascular disease (CVD) and cancer incidence. METHODS: We used data from 79,988 participants from the UK Biobank, a population-based prospective cohort study. Light PA (LPA), moderate-to-vigorous PA (MVPA), vigorous PA (VPA) and total PA (TPA) were measured using a wrist-worn accelerometer. Diet Quality Score (DQS) was based on 10 foods and ranged from 0 (unhealthiest) to 100 (healthiest) points. We derived joint PA and diet variables. Outcomes were all-cause mortality, CVD and cancer incidence including PA, diet and adiposity-related (PDAR) cancer. RESULTS: During a median follow-up of 8 years, 2,863 deaths occurred, 11,053 participants developed CVD, 7,005 developed cancer and 3,400 developed PDAR cancer. Compared with the least favourable referent group (bottom PA tertile/low DQS), participants with middle and high (total and intensity specific) PA, except for LPA, had lower all-cause mortality risk and incident CVD risk, regardless of DQS. For example, among middle and high VPA and high DQS groups, CVD HR were 0.79 (95%CI 0.74-0.86) and 0.75 (95%CI 0.69-0.82), respectively. The pattern of cancer results was less pronounced but in agreement with the ACM and CVD incidence findings (e.g. HR 0.90, 95%CI 0.81-0.99; 0.88,0.79-0.98 and 0.82,0.74-0.92 among high VPA for low, moderate and high DQS group, respectively). CONCLUSIONS: Device-measured PA reveals novel joint associations with diet on health outcomes. IMPACT: Our results emphasize the crucial role of PA in addition to a healthy diet for reducing chronic diseases and mortality risk.

Do the associations of daily steps with mortality and incident cardiovascular disease differ by sedentary time levels? A device-based cohort study.

OBJECTIVES: This study aims to examine the associations of daily step count with all-cause mortality and incident cardiovascular disease (CVD) by sedentary time levels and to determine if the minimal and optimal number of daily steps is modified by high sedentary time. METHODS: Using data from the UK Biobank, this was a prospective dose-response analysis of total daily steps across low (<10.5 hours/day) and high (≥10.5 hours/day) sedentary time (as defined by the inflection point of the adjusted absolute risk of sedentary time with the two outcomes). Mortality and incident CVD was ascertained through 31 October 2021. RESULTS: Among 72 174 participants (age=61.1±7.8 years), 1633 deaths and 6190 CVD events occurred over 6.9 (±0.8) years of follow-up. Compared with the referent 2200 steps/day (5th percentile), the optimal dose (nadir of the curve) for all-cause mortality ranged between 9000 and 10 500 steps/day for high (HR (95% CI)=0.61 (0.51 to 0.73)) and low (0.69 (0.52 to 0.92)) sedentary time. For incident CVD, there was a subtle gradient of association by sedentary time level with the lowest risk observed at approximately 9700 steps/day for high (0.79 (0.72 to 0.86)) and low (0.71 (0.61 to 0.83)) sedentary time. The minimal dose (steps/day associated with 50% of the optimal dose) of daily steps was between 4000 and 4500 steps/day across sedentary time groups for all-cause mortality and incident CVD. CONCLUSIONS: Any amount of daily steps above the referent 2200 steps/day was associated with lower mortality and incident CVD risk, for low and high sedentary time. Accruing 9000-10 500 steps/day was associated with the lowest mortality risk independent of sedentary time. For a roughly equivalent number of steps/day, the risk of incident CVD was lower for low sedentary time compared with high sedentary time.

Local orchestration of distributed functional patterns supporting loss and restoration of consciousness in the primate brain.

A central challenge of neuroscience is to elucidate how brain function supports consciousness. Here, we combine the specificity of focal deep brain stimulation with fMRI coverage of the entire cortex, in awake and anaesthetised non-human primates. During propofol, sevoflurane, or ketamine anaesthesia, and subsequent restoration of responsiveness by electrical stimulation of the central thalamus, we investigate how loss of consciousness impacts distributed patterns of structure-function organisation across scales. We report that distributed brain activity under anaesthesia is increasingly constrained by brain structure across scales, coinciding with anaesthetic-induced collapse of multiple dimensions of hierarchical cortical organisation. These distributed signatures are observed across different anaesthetics, and they are reversed by electrical stimulation of the central thalamus, coinciding with recovery of behavioural markers of arousal. No such effects were observed upon stimulating the ventral lateral thalamus, demonstrating specificity. Overall, we identify consistent distributed signatures of consciousness that are orchestrated by specific thalamic nuclei.

Contribution of Nutritional, Lifestyle, and Metabolic Risk Factors to Parkinson's Disease.

BACKGROUND: Modifiable risk factors for Parkinson's disease (PD) are poorly known. OBJECTIVES: The aim is to evaluate independent associations of different nutritional components, physical activity, and sedentary behavior and metabolic factors with the risk of PD. METHODS: In this population-based prospective cohort study using the data of the United Kingdom Biobank (from 2006-2010), 502,017 men and women who were free from PD (International Classification of Diseases 10th edition; "G20") at baseline were included. We implemented a Cox proportion hazard's model to evaluate the associations of different levels of physical activity, sitting time, sleep habits, diet quality, alcohol and coffee consumption, smoking, and body mass index with PD risk, adjusting for several confounding variables. RESULTS: During a median follow-up of 12.8 years, lifestyle factors including vigorous physical activity (hazard ration [HR] = 0.84; 95% confidence interval [CI], 0.75-0.94), low-to-moderate sitting time (HR = 0.89; 95% CI, 0.81-0.97), and high sleep quality (HR = 0.89; 95% CI, 0.80-0.99) were associated with a reduced risk of PD. Small amounts of coffee (HR = 0.88; 95% CI, 0.82-0.95), red meat (HR = 0.86; 95% CI, 0.76-0.97), and current smoking (HR = 0.65; 95% CI, 0.56-0.75) were also associated with a lower risk of PD, whereas alcohol intake (HR = 1.29; 95% CI, 1.06-1.56) with higher PD risk. Secondary analysis, including metabolic risk factors, confirmed these findings and highlighted the potential protective effect of plasma vitamin D and uric acid, but of low-density lipoprotein-cholesterol, triglycerides, and C-reactive protein as well. CONCLUSIONS: Vigorous physical activity, reduced sitting time, good sleep quality together with small coffee intake and vitamin D supplementation are potentially neuroprotective lifestyle interventions for the prevention of PD. © 2024 International Parkinson and Movement Disorder Society.

Associations of the 'weekend warrior' physical activity pattern with all-cause, cardiovascular disease and cancer mortality: the Mexico City Prospective Study.

OBJECTIVES: The objective was to investigate the benefits of the 'weekend warrior' physical activity pattern in Latin America, where many people take part in high levels of non-exercise physical activity. METHODS: Participants in the Mexico City Prospective Study were surveyed from 1998 to 2004 and resurveyed from 2015 to 2019. Those who exercised up to once or twice per week were termed weekend warriors. Those who exercised more often were termed regularly active. Analyses were adjusted for potential confounders. RESULTS: The main analysis included 26 006 deaths in 154 882 adults (67% female) aged 52±13 years followed for 18±4 years (mean±SD). Compared with those who reported no exercise, the HR (95% CI) was 0.88 (0.83 to 0.93) in the weekend warriors and 0.88 (0.84 to 0.91) in the regularly active. Similar results were observed for cardiovascular disease and cancer mortality, but associations were weaker. Stratified analyses showed that substantial reductions in all-cause mortality risk only occurred when the duration of exercise sessions was at least 30-60 min. The repeated-measures analysis included 843 deaths in 10 023 adults followed for 20±2 years. Compared with being inactive or becoming inactive, the HR was 0.86 (95% CI 0.65 to 1.12) when being a weekend warrior or becoming a weekend warrior and 0.85 (95% CI 0.70 to 1.03) when being regularly active or becoming regularly active. CONCLUSIONS: This is the first prospective study to investigate the benefits of the weekend warrior physical activity pattern in Latin America. The results suggest that even busy adults could benefit from taking part in one or two sessions of exercise per week.

Methylphenidate Ameliorates Behavioural and Neurobiological Deficits in Executive Function for Patients with Chronic Traumatic Brain Injury.

(1) Background: Traumatic brain injury (TBI) often results in cognitive impairments, including in visuospatial planning and executive function. Methylphenidate (MPh) demonstrates potential improvements in several cognitive domains in patients with TBI. The Tower of London (TOL) is a visuospatial planning task used to assess executive function. (2) Methods: Volunteers with a history of TBI (n = 16) participated in a randomised, double-blinded, placebo-controlled, fMRI study to investigate the neurobiological correlates of visuospatial planning and executive function, on and off MPh. (3) Results: Healthy controls (HCs) (n = 18) and patients on placebo (TBI-placebo) differed significantly in reaction time (p < 0.0005) and accuracy (p < 0.0001) when considering all task loads, but especially for high cognitive loads for reaction time (p < 0.001) and accuracy (p < 0.005). Across all task loads, TBI-MPh were more accurate than TBI-placebo (p < 0.05) but remained less accurate than HCs (p < 0.005). TBI-placebo substantially improved in accuracy with MPh administration (TBI-MPh) to a level statistically comparable to HCs at low (p = 0.443) and high (p = 0.175) cognitive loads. Further, individual patients that performed slower on placebo at low cognitive loads were faster with MPh (p < 0.05), while individual patients that performed less accurately on placebo were more accurate with MPh at both high and low cognitive loads (p < 0.005). TBI-placebo showed reduced activity in the bilateral inferior frontal gyri (IFG) and insulae versus HCs. MPh normalised these regional differences. MPh enhanced within-network connectivity (between parietal, striatal, insula, and cerebellar regions) and enhanced beyond-network connectivity (between parietal, thalamic, and cerebellar regions). Finally, individual changes in cerebellar-thalamic (p < 0.005) and cerebellar-parietal (p < 0.05) connectivity with MPh related to individual changes in accuracy with MPh. (4) Conclusions: This work highlights behavioural and neurofunctional differences between HCs and patients with chronic TBI, and that adverse differences may benefit from MPh treatment.

Information decomposition and the informational architecture of the brain.

To explain how the brain orchestrates information-processing for cognition, we must understand information itself. Importantly, information is not a monolithic entity. Information decomposition techniques provide a way to split information into its constituent elements: unique, redundant, and synergistic information. We review how disentangling synergistic and redundant interactions is redefining our understanding of integrative brain function and its neural organisation. To explain how the brain navigates the trade-offs between redundancy and synergy, we review converging evidence integrating the structural, molecular, and functional underpinnings of synergy and redundancy; their roles in cognition and computation; and how they might arise over evolution and development. Overall, disentangling synergistic and redundant information provides a guiding principle for understanding the informational architecture of the brain and cognition.

Clinical guidelines are silent on the recommendation of physical activity and exercise therapy for low back pain: A systematic review.

OBJECTIVES: To synthesise and evaluate the quality of the recommendations for exercise therapy and physical activity from guidelines for the prevention and/or management of low back pain. DESIGN: Systematic review. METHODS: Included clinical practice guidelines for the management of low back pain published between 2014 and 2022 and searched in 9 databases until September 2022. The quality of evidence was evaluated with the Appraisal of Guidelines, Research and Evaluation tool (AGREE-II instrument). RESULTS: After screening 3448 studies, 18 clinical practice guidelines were included in this review. Only five (27 %) guidelines were judged as having a satisfactory quality of evidence (i.e., rigour of development and applicability), and 13 (72 %) of guidelines are discussed and rated as critical. Regarding physical activity, no guidelines provided recommendations for the primary prevention of low back pain or incorporated adequate physical activity aspects considering type, dosage, frequency, and intensity. For exercises, all (100 %) guidelines recommended at least one type of supervised exercise in the management of low back pain, and 16 (88 %) provided an overall recommendation for people to stay active. CONCLUSIONS: Guidelines offer minimal or, sometimes, no detail regarding physical activity or specific exercise regimens for the management and prevention of low back pain. When some guidance is provided, the recommendations typically lack specificity concerning the type, intensity, duration, and frequency of exercise and, in many cases, they represent a combination of scarce available evidence and stakeholder perspectives.

Exercise Snacks and Other Forms of Intermittent Physical Activity for Improving Health in Adults and Older Adults: A Scoping Review of Epidemiological, Experimental and Qualitative Studies.

Exercise snacks, including other variants of brief intermittent bouts, are an emerging approach for increasing physical activity, although their operationalisation is unstandardised and their health benefits remain unclear. This scoping review aimed to explore characterisations of exercise snacks and summarise their effects on health in adults and older adults. Clinical trial registers (clinicaltrials.gov and ANZCTR) and electronic databases (PubMed, CINAHL, CENTRAL, PsycINFO) were searched from inception to 1 June 2023, for ongoing and published studies of exercise snacks. Backwards and forwards citation tracking was also conducted to identify additional eligible studies. Studies were included if they investigated exercise snacks-brief intermittent bouts of physical activity spread across the day-in adults or older adults. We included epidemiological, experimental, quasi-experimental and qualitative studies that examined the effect of exercise snacks on any health outcomes or described barriers to and enablers of these approaches. Thirty-two studies were included (7 trial registers, 1 published protocol, 3 epidemiological studies and 20 trials reported across 21 studies). Three main terms were used to describe exercise snacks: exercise snack(ing), snacktivity and vigorous intermittent lifestyle physical activity (VILPA). Participants were predominantly physically inactive but otherwise healthy adults or older adults. Exercise snacks were feasible and appeared safe. Epidemiological studies showed steep, near-linear associations of VILPA with reduced all-cause, cardiovascular and cancer mortality as well as reduced incidence of major adverse cardiovascular events and cancer. The limited trial evidence showed exercise snacks had modest effects on improving cardiorespiratory fitness, whereas effects on physical function, mood, quality of life and other health outcomes were equivocal. In conclusion, exercise snacks appear feasible and safe for adults and older adults and may have promising health benefits, but this is mostly based on findings from a limited number of small quasi-experimental studies, small randomised trials or qualitative studies. More studies are needed in individuals with chronic disease. This emerging physical activity approach may have appeal for individuals who find structured exercise unfeasible.Registration https://osf.io/qhu24/.

Device-measured physical activity and cardiometabolic health: the Prospective Physical Activity, Sitting, and Sleep (ProPASS) consortium.

BACKGROUND AND AIMS: Physical inactivity, sedentary behaviour (SB), and inadequate sleep are key behavioural risk factors of cardiometabolic diseases. Each behaviour is mainly considered in isolation, despite clear behavioural and biological interdependencies. The aim of this study was to investigate associations of five-part movement compositions with adiposity and cardiometabolic biomarkers. METHODS: Cross-sectional data from six studies (n = 15 253 participants; five countries) from the Prospective Physical Activity, Sitting and Sleep consortium were analysed. Device-measured time spent in sleep, SB, standing, light-intensity physical activity (LIPA), and moderate-vigorous physical activity (MVPA) made up the composition. Outcomes included body mass index (BMI), waist circumference, HDL cholesterol, total:HDL cholesterol ratio, triglycerides, and glycated haemoglobin (HbA1c). Compositional linear regression examined associations between compositions and outcomes, including modelling time reallocation between behaviours. RESULTS: The average daily composition of the sample (age: 53.7 ± 9.7 years; 54.7% female) was 7.7 h sleeping, 10.4 h sedentary, 3.1 h standing, 1.5 h LIPA, and 1.3 h MVPA. A greater MVPA proportion and smaller SB proportion were associated with better outcomes. Reallocating time from SB, standing, LIPA, or sleep into MVPA resulted in better scores across all outcomes. For example, replacing 30 min of SB, sleep, standing, or LIPA with MVPA was associated with -0.63 (95% confidence interval -0.48, -0.79), -0.43 (-0.25, -0.59), -0.40 (-0.25, -0.56), and -0.15 (0.05, -0.34) kg/m2 lower BMI, respectively. Greater relative standing time was beneficial, whereas sleep had a detrimental association when replacing LIPA/MVPA and positive association when replacing SB. The minimal displacement of any behaviour into MVPA for improved cardiometabolic health ranged from 3.8 (HbA1c) to 12.7 (triglycerides) min/day. CONCLUSIONS: Compositional data analyses revealed a distinct hierarchy of behaviours. Moderate-vigorous physical activity demonstrated the strongest, most time-efficient protective associations with cardiometabolic outcomes. Theoretical benefits from reallocating SB into sleep, standing, or LIPA required substantial changes in daily activity.

A role for the serotonin 2A receptor in the expansion and functioning of human transmodal cortex.

Integrating independent but converging lines of research on brain function and neurodevelopment across scales, this article proposes that serotonin 2A receptor (5-HT2AR) signalling is an evolutionary and developmental driver and potent modulator of the macroscale functional organization of the human cerebral cortex. A wealth of evidence indicates that the anatomical and functional organization of the cortex follows a unimodal-to-transmodal gradient. Situated at the apex of this processing hierarchy-where it plays a central role in the integrative processes underpinning complex, human-defining cognition-the transmodal cortex has disproportionately expanded across human development and evolution. Notably, the adult human transmodal cortex is especially rich in 5-HT2AR expression and recent evidence suggests that, during early brain development, 5-HT2AR signalling on neural progenitor cells stimulates their proliferation-a critical process for evolutionarily-relevant cortical expansion. Drawing on multimodal neuroimaging and cross-species investigations, we argue that, by contributing to the expansion of the human cortex and being prevalent at the apex of its hierarchy in the adult brain, 5-HT2AR signalling plays a major role in both human cortical expansion and functioning. Owing to its unique excitatory and downstream cellular effects, neuronal 5-HT2AR agonism promotes neuroplasticity, learning and cognitive and psychological flexibility in a context-(hyper)sensitive manner with therapeutic potential. Overall, we delineate a dual role of 5-HT2ARs in enabling both the expansion and modulation of the human transmodal cortex.