Beneficial Effects Of Physical Activity Research Articles

Association of Physical Activity With Primary Cardiac Arrest Risk in the General Population: A Nationwide Cohort Study of the Dose-Response Relationship

ObjectiveTo quantify the dose-response relationship between moderate to vigorous physical activity and primary cardiac arrest (PCA). Patients and MethodsThere were 504,840 participants older than 18 years who underwent the Korean National Health Screening Program, including a self-administered questionnaire for physical activity from January 1, 2009, through December 31, 2014. Physical activity levels were converted into metabolic equivalent tasks (METs) per week and categorized to correspond with multiples of public health recommendations. We evaluated the quantitative and categorical dose-response relationship between physical activity and PCA. ResultsA curvilinear dose-response relationship between physical activity and PCA was observed; the benefits started at two-thirds (5 MET-hour/week) of the United States and World Health Organization guidelines–recommended minimum (7.5 MET-hour/week) and continued to 5 times (40 MET-hour/week) the recommended minimum (P nonlinearity <.001). The largest benefit was noted at a level of 2 to 3 times the recommended minimum (hazard ratio, 0.6; 95% CI, 0.4 to 0.8). In addition, there was no evidence of an increased PCA risk at a level more than 5 times the recommended minimum (hazard ratio, 0.7; 95% CI, 0.5 to 1.1). These associations were consistent regardless of age, sex, body mass index, comorbid conditions, and estimated 10-year risk for cardiovascular disease. ConclusionThe beneficial effect of physical activity on PCA started at two-thirds of the recommended minimum and continued to 5 times the recommended minimum. No excess risk for PCA was present among individuals with activity levels more than 5 times the recommended minimum regardless of cardiovascular disease or lifestyle risk factor presence.

Does Regular Physical Activity Mitigate the Age-Associated Decline in Pulmonary Function?

Whereas the negative effects of aging and smoking on pulmonary function are undisputed, the potential favorable effects of physical activity on the aging process of the otherwise healthy lung remain controversial. This question is of particular clinical relevance when reduced pulmonary function compromises aerobic exercise capacity (maximal oxygen consumption) and thus contributes to an increased risk of morbidity and mortality. Here, we discuss whether and when the aging-related decline in pulmonary function limits maximal oxygen consumption and whether, how, and to what extent regular physical activity can slow down this aging process and preserve pulmonary function and maximal oxygen consumption. Age-dependent effects of reduced pulmonary function (i.e., FEV1, the volume that has been exhaled after the first second of forced expiration) on maximal oxygen consumption have been observed in several cross-sectional and longitudinal studies. Complex interactions between aging-related cellular and molecular processes affecting the lung, and structural and functional deterioration of the cardiovascular and respiratory systems account for the concomitant decline in pulmonary function and maximal oxygen consumption. Consequently, if long-term regular physical activity mitigates some of the aging-related decline in pulmonary function (i.e., FEV1 decline), this could also prevent a steep fall in maximal oxygen consumption. In contrast to earlier research findings, recent large-scale longitudinal studies provide growing evidence for the beneficial effects of physical activity on FEV1. Although further confirmation of those effects is required, these findings provide powerful arguments to start and/or maintain regular physical activity.

Cardiorespiratory fitness, screen time and cardiometabolic risk in South Brazilian school children

Background Cardiorespiratory fitness (CRF) is considered a beneficial effect of physical activity (PA). PA and excessive screen time have implications for cardiometabolic risk. Objective To verify the association between screen time and CRF grouped by cardiometabolic risk factors. Subjects and methods Cross-sectional study evaluated 1,253 schoolchildren (54.2% girls) aged seven to 17 years from southern Brazil. The outcomes were body mass index (BMI), waist circumference (WC), systolic blood pressure (SBP), and diastolic (DBP), glucose, and lipid profile. Exposure was a combined variable of self-reported screen time (television, video game, computer) and CRF. Results The main result is that CRF had a more consistent association with anthropometric factors than with metabolic variables. Low CRF students, regardless of screen time, showed a 15% increase in the risk of elevated WC (p < 0.001) and a 24% (<2 h screen time) and 19% (≥2 h) higher risk of overweight (p < 0.001). Second, the increase in SBP was associated with a combination of the two risk factors, ≥2 h screen time/low CRF was associated with a 7% increase in elevated SBP (p = 0.025). Conclusion Low CRF was a risk factor for elevated BMI and WC, regardless of screen time. High screen time and low CRF were associated with higher SBP values.

Molecular mechanisms of adaptive and therapeutic effects of physical activity in patients with cardiovascular diseases

Physical activity is one of the main components of the rehabilitation of patients with cardiovascular disease (CVD). As shown by practice and the results of evidence-based studies, the beneficial effects of physical activity on disease outcomes in a number of cardiac nosologies are comparable to drug treatment. This gives the doctor another tool to influence the unfavorable epidemiological situation in developed countries with the spread of diseases of the cardiovascular system and CVD mortality. Reliable positive results of cardiorehabilitation (CR) were obtained using various methods. The goal of CR is to restore the optimal physiological, psychological and professional status, reduce the risk of CVD and mortality. In most current CVD guidelines worldwide, cardiac rehabilitation is a Class I recommendation. The molecular mechanisms described in the review, initiated by physical activity, underlie the multifactorial effect of the latter on the function of the cardiovascular system and the course of cardiac diseases. Physical exercise is an important component of the therapeutic management of patients with CVD, which is supported by the results of a meta-analysis of 63 studies associated with various forms of aerobic exercise of varying intensity (from 50 to 95% VO2) for 1 to 47 months, which showed that CR based on physical exercise improves cardiorespiratory endurance. Knowledge of the molecular basis of the influence of physical activity makes it possible to use biochemical markers to assess the effectiveness of rehabilitation programs.

The Role of Physical Activity in Opioid Substitution Therapy: A Systematic Review of Interventional and Observational Studies.

Background:Use of physical activity in the treatment and follow-up of people receiving opioid substitution therapy is an understudied area of research. Therefore, the objective of this systematic review was to synthesize the currently available research on the role of physical activity in opioid substitution therapy and proper adaptions for the group.Methods:A systematic search was performed on PsycINFO, EMBASE, MEDLINE, CINAHL, and Web of Science until September 2021 (PROSPERO-reg.no: CRD42020109873). The inclusion criteria were studies involving physical activity interventions for opioid substitution patients. Reference lists of relevant studies were screened to identify additional relevant studies. Data extracted were compiled into tables and descriptively presented.Results:The search yielded 2105 unique records. A total of 10 studies were included, whose methodological quality ranged from satisfactory to very good. Study quality was assessed using a 7-/8-point quality score. The agreement between the reviewers, assessed with Cohen’s kappa, was 0.91. Overall, the results suggest that physical activity increases physical fitness of patients in opioid substitution therapy and decreases substance use. The minority of studies in this field are of high quality with sufficient power.Conclusions:The findings of this systematic review suggest beneficial effects of physical activity on physical fitness, substance use, and mental health for patients in opioid substitution therapy. Although the findings are quite consistent across studies, high-quality studies and sufficiently powered clinical trials are needed to confirm and validate the findings and to conclude on the degree of impact.

The Effects of Physical Exercise on Mental Health: From Cognitive Improvements to Risk of Addiction

(1) Background: we aimed to investigate the effects of physical activity on cognitive functions and deficits of healthy population and other needy groups. Secondly, we investigated the relation between healthy habits and psychopathological risks. Finally, we investigated the impact of COVID-19 pandemic on exercise addiction and possible associated disorders. (2) Methods: From April 2021 to October 2021, we conducted a review aimed at identifying the effects of physical exercise on mental health, from cognitive improvements to risk of addiction; we searched for relevant studies on PubMed, Web of Science, EMBASE, PsycINFO and CINHAL. (3) Results: For the first purpose, results indicated multiple effects such as better precision and response speed in information processing tasks on healthy populations; improvement of executive functions, cognitive flexibility and school performance in children; improvement of attention and executive functions and less hyperactivity and impulsiveness on children with attention deficit hyperactivity disorder (ADHD); improvement of executive and global functions on adults; improvement of overall cognitive functioning on patients with schizophrenic spectrum disorder or bipolar disorder. Data also demonstrated that exercise addiction seems to be related to low levels of education, low self-esteem, eating disorders and body dysmorphisms. Eventually, it was found that people with lower traits and intolerance of uncertainty show a strong association between COVID-19 anxiety and compulsive exercise and eating disorder. (4) Conclusions: these findings underline on one side the beneficial effects of physical activity on cognitive function in healthy individuals in a preventive and curative key, while on the other side the importance of an adequate evaluation of psychological distress and personality characteristics associated with exercise addiction.

Mediators between physical activity and academic achievement: A systematic review.

Research has suggested the beneficial effects of physical activity (PA) on academic achievement (AA). However, the mechanisms underlying this influence remain unclear. Some proposed mechanisms include physiological, cognitive, psychological, and behavioral paths. This study aimed to analyze mediators between PA and AA in children and adolescents. Systematic search in Medline, SPORTDiscuss, PsycInfo, Scopus, and Web of Science for observational and experimental studies, published up to March 2021. Twenty-eight studies (75237 participants, aged 4-16) were included. The designs of these studies were: 21 studies cross-sectional, 5 longitudinal, and 2 experimental. Eight out of nine studies analyzing fitness as a mediator reported positive results, and one reported null finding. Adiposity was a significant mediator in one study, in two only in girls, and two reported null results. Cognition as a mediator was supported by four studies, whereas two reported null results. Regarding mental well-being, 10 out of 14 studies reported positive effects, and one out of five behavioral studies found positive results. Although studies were too sparse to draw conclusions, overall, the results indicated that self-esteem, self-image, self-efficacy, stress, and health behaviors might be potential mediators in the relationship between PA and AA. All studies were rated as medium-high quality. Overall, the available evidence seems to suggest that cardiorespiratory fitness, cognition, mental well-being, and exercise-related behaviors play some role as mediators of the relationship between PA and AA. However, the cross-sectional nature of most of the reviewed studies prevents us from making any statement in terms of causal paths. Thus, well-designed follow-up and randomized controlled studies aimed not only to tests the effect of PA in AA, but also to examine the influence of mediators are required.

Active Life for Brain Health: A Narrative Review of the Mechanism Underlying the Protective Effects of Physical Activity on the Brain.

A growing body of evidence clearly indicates the beneficial effects of physical activity (PA) on cognition. The importance of PA is now being reevaluated due to the increase in sedentary behavior in older adults during the COVID-19 pandemic. Although many studies in humans have revealed that PA helps to preserve brain health, the underlying mechanisms have not yet been fully elucidated. In this review, which mainly focuses on studies in humans, we comprehensively summarize the mechanisms underlying the beneficial effects of PA or exercise on brain health, particularly cognition. The most intensively studied mechanisms of the beneficial effects of PA involve an increase in brain-derived neurotrophic factor (BDNF) and preservation of brain volume, especially that of the hippocampus. Nonetheless, the mutual associations between these two factors remain unclear. For example, although BDNF presumably affects brain volume by inhibiting neuronal death and/or increasing neurogenesis, human data on this issue are scarce. It also remains to be determined whether PA modulates amyloid and tau metabolism. However, recent advances in blood-based biomarkers are expected to help elucidate the beneficial effects of PA on the brain. Clinical data suggest that PA functionally modulates cognition independently of neurodegeneration, and the mechanisms involved include modulation of functional connectivity, neuronal compensation, neuronal resource allocation, and neuronal efficiency. However, these mechanisms are as yet not fully understood. A clear understanding of the mechanisms involved could help motivate inactive persons to change their behavior. More accumulation of evidence in this field is awaited.

Exercise Training: The Holistic Approach in Cardiovascular Prevention.

Nowadays, there are robust clinical and pathophysiological evidence supporting the beneficial effects of physical activity on cardiovascular (CV) system. Thus, the physical activity is considered a key strategy for CV prevention. In fact, exercise training exerts favourable effects on all risk factors for CV diseases (i.e. essential hypertension, type 2 diabetes mellitus, hypercholesterolemia, obesity, metabolic syndrome, etc…). In addition, all training modalities such as the aerobic (continuous walking, jogging, cycling, etc.) or resistance exercise (weights), as well as the leisure-time physical activity (recreational walking, gardening, etc) prevent the development of the major CV risk factors, or delay the progression of target organ damage improving cardio-metabolic risk. Exercise training is also the core component of all cardiac rehabilitation programs that have demonstrated to improve the quality of life and to reduce morbidity in patients with CV diseases, mostly in patients with coronary artery diseases. Finally, it is still debated whether or not exercise training can influence the occurrence of atrial and ventricular arrhythmias. In this regard, there is some evidence that exercise training is protective predominantly for atrial arrhythmias, reducing the incidence of atrial fibrillation. In conclusion, the salutary effects evoked by physical acitvity are useful in primary and secondary CV prevention.

It’s all about control: Sense of control mediates the relationship between physical activity and mental health during the COVID-19 pandemic in Germany

COVID-19-related burden has a significant impact on mental health and has led to an increase of depression, anxiety, and stress symptoms. Physical activity has been suggested to mitigate the negative effects of the pandemic and to foster mental health. The present study aimed to investigate, whether sense of control might mediate the supposed beneficial effects of physical activity on positive (PMH) and negative mental health (NMH) in unpredictable extraordinary situations. Data were assessed in a sample of 568 students (Mage = 19.90, SDage = 4.52) from Germany via an online survey in fall 2020. Mediation analyses revealed that sense of control mediated the relation between physical activity and PMH as well as depression, anxiety, and stress symptoms, respectively. The findings indicate that physical activity may be a promising strategy for fostering sense of control and thus mental health. Due to its practical implications and practicability, engagement in physical activity could be an effective way to reduce the NMH consequences of the current COVID-19 situation, and therefore should be addressed in actions for long-term prevention and intervention.

The beneficial effect of physical activity on cognitive function in community-dwelling older persons with locomotive syndrome

BackgroundCognitive decline is closely related to motor decline. Locomotive syndrome (LS) is defined as a state associated with a high risk of requiring support because of locomotive organ disorders, and can be evaluated using a questionnaire. This study aimed to clarify the effectiveness of daily goal-targeted exercise on cognitive function in two different populations classified by scores on the Locomo 25 questionnaire.MethodsSeventy community-dwelling older people who participated in a 13-week health class were divided into two populations based on Locomo 25 scores: <7 (non-LS) and ≥7 (LS). Participants were presented with a daily target steps and worked towards that goal. Cognitive function was evaluated using the Japanese version of Addenbrooke’s Cognitive Examination-Revised (ACE-R). Average daily physical activity (exercise [Ex]) for 13 weeks was measured using a portable activity meter. Depression status was assessed using the Geriatric Depression Scale (GDS-15).ResultsNo significant differences were observed in age, years of education, body mass index, smooth muscle mass index, GDS-15 scores, or ACE-R scores between the non-LS and LS populations. Multiple logistic regression analysis showed that Ex (odds ratio = 5.01, p = 0.002) for 13 weeks was significantly associated with increased cognitive function in the LS population. The Ex threshold for the increase in cognitive function based on receiver operating curve analysis was 2.29 metabolic equivalents of task (METs) × h (METs · h/day) (p = 0.047) in the LS population. After 13 weeks, ACE-R scores were significantly higher in the Ex ≥ 2.29 than in the Ex < 2.29 METs · h/day group (p = 0.024, ηp2 = 0.241) in the LS population based on two-way analysis of covariance. Furthermore, a significant increase in the ACE-R memory domain was seen in the Ex ≥ 2.29 group (p = 0.035, ηp2 = 0.213).ConclusionsThese results suggest that Ex ≥ 2.29 METs · h/day is important for improving cognitive function in LS populations.

Physical Inactivity and COVID-19: When Pandemics Collide

The 3 new Lancet series papers on physical activity1–3 build on the evidence presented in 2 previous series that underlined the pandemic magnitude of physical inactivity, its health, social, environmental and economic global consequences, and the urgency to take immediate multisectoral actions to make active living an affordable and accessible choice for all population groups. These messages were based on unquestionable evidence of the beneficial effects of physical activity on virtually every system of the body, supporting it as a “best buy in public health.” Increasing physical activity could save 5.3 million lives per year,4 and it is critical for the prevention and control of multiple noncommunicable diseases (NCDs) that account for 74% of deaths globally. However, an estimated 1 in 3 adults and 3 in 4 adolescents worldwide did not meet the physical activity guidelines before the pandemic. Now in 2021, the failure to take seriously evidence-based recommendations to increase physical activity has contributed to the estimated 4.2 million COVID-19 deaths worldwide. It is clear that the inactivity pandemic is foundational in the global explosion of NCDs that have collided so tragically with the COVID-19 pandemic.

The genetics of human performance.

Human physiology is likely to have been selected for endurance physical activity. However, modern humans have become largely sedentary, with physical activity becoming a leisure-time pursuit for most. Whereas inactivity is a strong risk factor for disease, regular physical activity reduces the risk of chronic disease and mortality. Although substantial epidemiological evidence supports the beneficial effects of exercise, comparatively little is known about the molecular mechanisms through which these effects operate. Genetic and genomic analyses have identified genetic variation associated with human performance and, together with recent proteomic, metabolomic and multi-omic analyses, are beginning to elucidate the molecular genetic mechanisms underlying the beneficial effects of physical activity on human health.

Rehabilitation of Patients with Severe Disability after coVID-19 in Rehabilitation Department. Multiple Case Study

The review analyzes the data of scientific publications on the effects of molecular mechanisms initiated by physical exertion on thefunction of the cardiovascular system and the course of cardiac diseases. As practice and a number of evidence-based studies haveshown, the beneficial effects of physical activity on the outcomes of diseases in a number of cardiac nosologies are comparable todrug treatment. Numerous mechanisms mediate the benefits of regular exercise for optimal cardiovascular function. Exercises causewidespread changes in numerous cells, tissues, and organs in response to increased metabolic demand, including adaptation of thecardiovascular system. Physical exercises, which include various types of aerobic exercises of varying intensity and duration, is animportant component of the therapeutic treatment of patients with cardiovascular diseases. Knowledge of the molecular basis ofthe physical activity impact on the cardiovascular system makes it possible to use biochemical markers to assess the effectiveness ofrehabilitation programs.

Postprandial interval walking—effect on blood glucose in pregnant women with gestational diabetes

During pregnancy, postprandial hyperglycemia may increase the risk of complications such as fetal macrosomia. However, evidence on beneficial effects of physical activity on postprandial hyperglycemia is sparse. This study aimed to investigate the effect of 20 minutes of postprandial interval walking on glycemic control and glycemic variability in pregnant women diagnosed as having gestational diabetes mellitus. A crossover controlled trial including 14 pregnant women (gestational age 31.8±1.3 weeks) diagnosed as having gestational diabetes mellitus (75 g oral glucose load with 2-hour venous plasma glucose of ≥9.0 mmol/L) was conducted. Participants completed a 4-day intervention period and a 4-day control period with 3 days in between. In each study period, participants received a fixed and identical diet. In the intervention period, participants engaged in 20 minutes of postprandial interval walking after breakfast, lunch, and dinner. Interval walking comprised alternating 3 minutes of slow and fast intervals. Interstitial glucose concentrations were determined during both study periods with a continuous glucose monitor. The mixed effects model was used to compare differences between exercise and no exercise. Of note, 20 minutes of postprandial interval walking significantly reduced glycemic control during daytime hours relative to the control period (4-day mean glucose, 5.31 [5.04-5.59] vs 5.53 [5.25-5.81] mmol/L [95.6 (90.7-100.6) vs 99.5 (94.5-104.6) mg/dL]; P<.05). On each individual trial day, interval walking significantly reduced glycemic control during daytime hours on day 1 (mean glucose, 5.19 [4.92-5.47] vs 5.55 [5.27-5.83] mmol/L [93.4 (88.6-98.5) vs 99.9 (94.9-104.9) mg/dL]; P=.00), day 2 (mean glucose, 5.32 [5.05-5.60] vs 5.57 [5.29-5.84] mmol/L [95.8 (90.9-100.8) vs 100.3 (95.2-105.1) mg/dL]; P=.00), and day 3 (mean glucose, 5.27 [5.00-5.54] vs 5.46 [5.19-5.74] mmol/L [94.9 (90.0-99.7) vs 98.3 (93.4-103.3) mg/dL]; P=.00), but not on day 4. A total of 20 minutes of postprandial interval walking seems to be an effective way to control postprandial glucose excursions in women with gestational diabetes mellitus.

The Impact of Healthy Lifestyles on Late Sequelae in Classical Hodgkin Lymphoma and Diffuse Large B-Cell Lymphoma Survivors. A Systematic Review by the Fondazione Italiana Linfomi.

Simple SummaryWith the presented study, Fondazione Italiana Linfomi (FIL) researchers want to fill a gap in the literature regarding long-lived lymphoma patients (beyond 5 years after diagnosis). These patients can develop a series of late sequelae that affect their quality of life and overall survival, especially cardiotoxicity and secondary malignancies. In this context, although part of the risk is closely related to the chemotherapy and radiotherapy, some risk factors can be modified through tertiary prevention. There are currently no specific indications for tertiary prevention in the subset of long-term lymphoma survivors. This systematic review conducted by the FIL researchers is aimed at understanding whether there is evidence that correcting unhealthy lifestyles can reduce the onset of late sequelae.Background: In recent years, the scientific community has been paying ever more attention to the promotion of lifestyles aimed at the prevention of late toxicities related to anti-cancer treatments. Methods: Fondazione Italiana Linfomi (FIL) researchers conducted a systematic review in order to evaluate the evidence in favor of the promotion of lifestyles aimed at the prevention of the main sequelae of long-term classical Hodgkin lymphoma (cHL) and diffuse large B-cell lymphoma (DLBCL) in survivors treated at adulthood with first-line or second-line therapy, including autologous stem cell transplants (ASCTs). Pubmed, Embase and Cochrane Library were searched up to December 2020. Results: Seven studies were ultimately included in this systematic review; some of them were eligible for multiple PICOS. The majority of the studies emerged from data extraction regarding cHL; less evidence resulted for DLBCL survivors. Five studies in favor of physical activity provided consistent data for a reduction of the cardiovascular risk in cHL and also in survivors who underwent ASCT. A beneficial effect of physical activity in reducing chronic fatigue was found. Being overweight was associated with a higher risk of coronary heart disease in cHL survivors in one of the two eligible studies. Studies aiming to evaluate the impact of the Mediterranean diet on late toxicities and secondary cancers were lacking. Tailored survivorship care plans (SCP) seemed to represent an optimal tool to guide the follow-up and promote healthier lifestyles in the one eligible study. Thus, promotion of healthy lifestyles and empowering of lymphoma survivors should be implemented through structured models. The study also brought to light numerous areas of future clinical research.

Neuroprotective Effects of Physical Activity via the Adaptation of Astrocytes.

The multifold benefits of regular physical exercise have been largely demonstrated in human and animal models. Several studies have reported the beneficial effects of physical activity, both in peripheral tissues and in the central nervous system (CNS). Regular exercise improves cognition, brain plasticity, neurogenesis and reduces the symptoms of neurodegenerative diseases, making timeless the principle of “mens sana in corpore sano” (i.e., a healthy mind in a healthy body). Physical exercise promotes morphological and functional changes in the brain, acting not only in neurons but also in astrocytes, which represent the most numerous glial cells in the brain. The multiple effects of exercise on astrocytes comprise the increased number of new astrocytes, the maintenance of basal levels of catecholamine, the increase in glutamate uptake, the major release of trophic factors and better astrocytic coverage of cerebral blood vessels. The purpose of this review is to highlight the effects of exercise on brain function, emphasize the role of astrocytes in the healthy CNS, and provide an update for a better understanding of the effects of physical exercise in the modulation of astrocyte function.

Cardiac Biomarkers and Autoantibodies in Endurance Athletes: Potential Similarities with Arrhythmogenic Cardiomyopathy Pathogenic Mechanisms.

The “Extreme Exercise Hypothesis” states that when individuals perform training beyond the ideal exercise dose, a decline in the beneficial effects of physical activity occurs. This is due to significant changes in myocardial structure and function, such as hemodynamic alterations, cardiac chamber enlargement and hypertrophy, myocardial inflammation, oxidative stress, fibrosis, and conduction changes. In addition, an increased amount of circulating biomarkers of exercise-induced damage has been reported. Although these changes are often reversible, long-lasting cardiac damage may develop after years of intense physical exercise. Since several features of the athlete’s heart overlap with arrhythmogenic cardiomyopathy (ACM), the syndrome of “exercise-induced ACM” has been postulated. Thus, the distinction between ACM and the athlete’s heart may be challenging. Recently, an autoimmune mechanism has been discovered in ACM patients linked to their characteristic junctional impairment. Since cardiac junctions are similarly impaired by intense physical activity due to the strong myocardial stretching, we propose in the present work the novel hypothesis of an autoimmune response in endurance athletes. This investigation may deepen the knowledge about the pathological remodeling and relative activated mechanisms induced by intense endurance exercise, potentially improving the early recognition of whom is actually at risk.

Exercise mimetics: harnessing the therapeutic effects of physical activity.

Exercise mimetics are a proposed class of therapeutics that specifically mimic or enhance the therapeutic effects of exercise. Increased physical activity has demonstrated positive effects in preventing and ameliorating a wide range of diseases, including brain disorders such as Alzheimer disease and dementia, cancer, diabetes and cardiovascular disease. This article discusses the molecular mechanisms and signalling pathways associated with the beneficial effects of physical activity, focusing on effects on brain function and cognitive enhancement. Emerging therapeutic targets and strategies for the development of exercise mimetics, particularly in the field of central nervous system disorders, as well as the associated opportunities and challenges, are discussed.

The joint association of physical activity and fine particulate matter exposure with incident dementia in elderly Hong Kong residents.

The evidence for the beneficial effects of physical activity (PA) and potentially detrimental effects of long-term exposure to fine particulate matter (PM2.5) on neurodegeneration diseases is accumulating. However, their joint effects remain unclear. We evaluated joint associations of habitual PA and PM2.5 exposure with incident dementia in a longitudinal elderly cohort in Hong Kong. A total of 57,775 elderly participants (≥65years) without dementia were enrolled during 1998-2001 and followed up till 2011. Their information on PA and other relevant covariates were collected at baseline (1998-2001) by a standard self-administered questionnaire, including PA volumes (high, moderate, low, and inactive) and types (aerobic exercise, traditional Chinese exercise, stretching exercise, walking slowly, and no exercise). Their annual mean PM2.5 exposures at the residential address were estimated using a satellite-based spatiotemporal model. We then adopted the Cox proportional hazards model to examine the joint associations with the incidence of all-cause dementia, Alzheimer's diseases, and vascular dementia on additive and multiplicative scales. During the follow-up period, we identified 1,157 incident cases of dementia, including 642 cases of Alzheimer's disease and 324 cases of vascular dementia. A higher PA level was associated with a lower risk of incident all-cause dementia (hazard ratio (HR) for the high-PA volume was 0.59 (95% CI, 0.47, 0.75), as compared with the inactive-PA), whereas a high level of PM2.5 was related to the higher risk with an HR of 1.15 (95%CI: 1.00, 1.33) compared with the low-level of PM2.5. No clear evidence was observed of interaction between habitual PA (volume and type) and PM2.5 inhalation to incident dementia on either additive or multiplicative scale. Habitual PA and long-term PM2.5 exposure were oppositely related to incident dementia in the Hong Kong aged population. The benefits of PA remain in people irrespective of exposure to air pollution.