Increase of circulating BDNF levels and its relation to improvement of physical fitness following 12 weeks of combined exercise in chronic patients with schizophrenia: a pilot study

"InMotion"-Mixed physical exercise program with creative movement as an intervention for adults with schizophrenia: study protocol for a randomized controlled trial

Background

Schizophrenia is among the world's top 10 causes of long-term disability with symptoms that lead to major problems in social and occupational functioning, and in self-care. Therefore, it is important to investigate the efficacy of complementary treatment options for conventionally used antipsychotic medication, such as physical training, and psychosocial interventions.

Objective

To combine aerobic and strength training with cognitive, emotional and social stimulation in one intervention for people with schizophrenia and test the feasibility and effects of this intervention.

Methods

The study is a mixed-method randomized controlled trial to evaluate the effects of a 12-week intervention for adults with schizophrenia. The treatment group (30 participants) will receive the intervention in addition to standard care and the control group (30 participants) only standard care. The intervention consists of 24 biweekly sessions with a duration of 60 min. The pre-test (weeks from 4 to 2 prior to the intervention) and post-test (week 12) include clinical measure (PANSS), quality of life, social performance, movement quantity, brain function and eye tracking measures. In addition, a treatment subgroup of 12-15 participants and their family member or other next of kin will complete a qualitative interview as a part of their post-test. Two follow-up tests, including clinical, quality of life, brain function and eye tracking will be made at 6 and 12 months from the completion of the intervention to both study groups. The primary outcome is change in negative symptoms. Secondary outcome measures include general and positive symptoms, quality of life, social performance, movement quantity, brain function and eye tracking. Explorative outcome includes patient and family member or other next of kin interview.

Results

Pilot data was collected by June 2023 and the main data collection will begin in September 2023. The final follow-up is anticipated to be completed by 2026.

Conclusion

The InMotion study will provide new knowledge on the feasibility, efficacy, and experiences of a novel intervention for adults with schizophrenia. The hypothesis is that regular participation in the intervention will reduce clinical symptoms, normalize physiological measures such as brain activation, and contribute to new active habits for the participants.

Trial registration

ClinicalTrials.gov, identifier NCT05673941.

The efficacy of exercise interventions for all types of inpatients across mental health settings: A systematic review and meta-analysis of 47 studies

This systematic review and meta-analysis investigated the benefits, safety and adherence of exercise interventions delivered in inpatient mental health settings, quantified the number of exercise trials that provided support to maintain engagement in exercise post-discharge, and reported patient feedback towards exercise interventions. Major databases were searched from inception to 22.06.2022 for intervention studies investigating exercise in mental health inpatient settings. Study quality was assessed using Cochrane and ROBINS-1 checklists. Fifty-six papers were included from 47 trials (including 34 RCTs), bias was high. Exercise improved depression (Standardised mean difference = -0.416; 95% Confidence interval -0.787 to -0.045, N = 15) compared to non-exercise comparators amongst people with a range of mental illnesses, with further (albeit limited) evidence suggesting a role of exercise in cardiorespiratory fitness and various other physical health parameters and ameliorating psychiatric symptoms. No serious exercise-related adverse events were noted, attendance was ≥80% in most trials, and exercise was perceived as enjoyable and useful. Five trials offered patients post-discharge support to continue exercise, with varying success. In conclusion, exercise interventions may have therapeutic benefits in inpatient mental health settings. More high-quality trials are needed to determine optimal parameters, and future research should investigate systems to support patients to maintain exercise engagement once discharged.

A combined exercise and cognitive training intervention induces fronto-cingulate cortical plasticity in first-episode psychosis patients

OBJECTIVE

Schizophrenia (SZ) is characterized by neurobiological and associated cognitive and functional deficits, including pronounced cortical thinning, that lead to acute and long-term functional impairment. Research with older adults supports the role of non-pharmacological interventions, such as exercise (E) and cognitive training (CT), for cognitive impairments. This literature influenced the development of combined CT&E treatments for individuals with SZ. However, the impact of longer combined treatment duration (6 months) on neuroanatomy has yet to be explored in patients in the early course of the illness. The impact of adding exercise to cognitive training for key brain regions associated with higher-order cognition was examined here using magnetic resonance imaging (MRI) in first-episode psychosis (FEP) patients.

METHODS

UCLA Aftercare Research Program patients with a recent first episode of schizophrenia were randomly assigned to either combined cognitive and exercise training (CT&E) (N = 20) or cognitive training alone (CT) (N = 17) intervention. Cortical thickness was measured longitudinally and analyzed for two regions of interest using FreeSurfer.

RESULTS

Compared to patients in the CT group, those in the CT&E group demonstrated an increase in cortical thickness within the left anterior cingulate cortex over the six-month treatment period (ACC: F(1, 35) = 4.666, P < .04). Directional tendencies were similar in the left dorsolateral prefrontal cortex (DLPFC: F(1,35) = 4.132, P < .05).

CONCLUSIONS

These findings suggest that exercise and cognitive training may synergistically increase fronto-cingulate cortical thickness to mitigate progressive neural atrophy in the early course of SZ. This combined intervention appears to be a valuable adjunct to standard pharmacologic treatment in FEP patients.

Concurrent Training Increases Serum Brain-Derived Neurotrophic Factor in Older Adults Regardless of the Exercise Frequency

Background

Human brain function declines with aging. In this sense, exercise-based interventions has a promising effect on brain plasticity for older adults. Serum brain-derived neurotrophic factor (BDNF) is a positive biomarker for brain neuroplasticity in healthy older adults also modified by exercise training. Selected features of the exercise prescription for improving brain health are missing; therefore, the aim of this study was to determine the effects of concurrent exercise training frequency on serum BDNF levels in healthy older adults.

Methods

Nineteen volunteers (age: 65 ± 4 year; body mass index: 28.0 ± 4.5 kg/m²) completed either a three times/week (3-t/w) (n = 8) or five times/week (5-t/w) (n = 11) concurrent exercise program. The exercise program lasted 11 weeks and all exercise sessions were performed for 50 min at moderate intensity. Serum BDNF, body composition, cardiovascular, and physical fitness variables were assessed before and after the exercise training program.

Results

Regardless of the group, the serum BDNF increased following the intervention (p < 0.001), and there were no significant group (p = 0.827) or interaction (p = 0.063) effects. The maximal oxygen consumption (VO2max) increased regardless of the group (p = 0.007), with a non-significant group (p = 0.722) or interaction (p = 0.223) effects. Upper- and lower-body strength increased in both groups (p = 0.003); however, there was no effect of the training frequency (p = 0.53). For the skeletal muscle mass, there was a trend in the interaction effect (p = 0.053). Finally, the body fat percentage was unchanged.

Conclusion

Eleven weeks of combined exercise training increased serum BDNF levels in healthy older adults, a response independent of the training frequency. The overall fitness level improved similarly in both exercise groups. These data reveal that a minimal dosage of concurrent exercise enhance functional capacity and a brain health biomarker in older adults.

Time-course effects of functional fitness sessions performed at different intensities on the metabolic, hormonal, and BDNF responses in trained men

Background

To investigate the time-course effects of a self-regulated training session (performed at an rating perceived exertion of 6/10), all-out session, and a control session on the metabolic, hormonal, and brain derived neurotrophic factor (BDNF) responses in Functional-Fitness (FFT) participants.

Methods

In a randomized, crossover fashion, eight healthy males (age 28.1 ± 5.4 years old; body mass 77.2 ± 4.4 kg; VO_2max: 52.6 ± 4.6 mL.(kg.min)⁻¹; 2000 m rowing test 7.35 ± 0.18 min; 1RM back squat 135.6 ± 21.9 kg) performed a FFT session under two different conditions: all-out, or with the intensity controlled to elicit an rating perceived exertion (RPE) of 6 in the Borg 10-point scale (RPE6). A control session (no exercise) was also completed. Metabolic (lactate and creatine kinase), hormonal (testosterone and cortisol), and BDNF responses were assessed pre, post-0 h, 1 h, 2 h and 24 h after the sessions.

Results

Creatine kinase concentrations were significantly higher (p ≤ 0.05) after 24 h for both training sessions. Total and free testosterone concentrations were lower post-2 h for all-out when compared to the RPE6 session (p ≤ 0.05). Serum cortisol concentration increased post-0 h (p = 0.011) for RPE6 and post-0 h (p = 0.003) and post-1 h (p = 0.030) for all-out session when comparing to baseline concentrations. BDNF was significantly higher (p = 0.002) post-0 h only for the all-out session when compared to baseline. A positive correlation between blood lactate concentrations and BDNF (r = 0.51; p = 0.01) was found for both effort interventions.

Conclusions

A single FFT session when performed in all-out format acutely increases the concentrations of serum BDNF. However, physiological stress markers show that the all-out session requires a longer recovery period when compared to the RPE6 protocol. These findings can be helpful to coaches and practitioners design FFT session.

Comparison of three different exercise training modalities (aerobic, strength and mixed) in patients with schizophrenia: study protocol for a multicentre randomised wait-list controlled trial

INTRODUCTION

Numerous studies support the practice of different physical exercise modalities as an effective treatment to address the problems associated with schizophrenia, reporting that they result in improvements in patient symptoms and quality of life. Given the lack of studies comparing different types of training in controlled environments, the aim of this proposed study will be to compare the effects of three physical exercise programmes (strength, aerobic and mixed) on the symptoms, body composition, level of physical activity and health-related quality of life of patients with schizophrenia.

METHODS AND ANALYSIS

A multicentre, single-blinded (evaluator), randomised, wait-list controlled (ratio 2:2:2:1) trial will be conducted with 105 patients recruited from different psychosocial care centres. The participants will be randomised into three 16-week training groups comprising 48 sessions lasting 1 hour each, or to the wait-list control group. The training groups will complete aerobic, strength or mixed (aerobic+strength) training. The participants will be assessed before, immediately after and 6 months after the end of the intervention. The patients in the wait-list control group (n=15) will receive one of the three trainings immediately after the intervention. The study variables will include positive, negative and general symptomology (Positive and Negative Syndrome Scale) as the primary outcome; as secondary outcome: body composition (by assessing body mass index, body fat mass and waist circumference), physical activity levels (International Physical Activity Questionnaire-Short Form) and quality of life (abbreviated WHO Quality of Life questionnaire).

ETHICS AND DISSEMINATION

This study was approved by the ethics committees for Biomedical Research at the CEU Cardenal Herrera University of Valencia, Spain (CEI18/215). Participants will be fully informed of the purpose and procedures of the study, and written informed consent will be obtained. The results from this study will be published in peer-reviewed journals and presented in scientific conferences.

TRIAL REGISTRATION NUMBER

NCT04987151.

A randomized controlled trial of exercise on augmenting the effects of cognitive remediation in persons with severe mental illness

BACKGROUND

Preliminary evidence suggests that aerobic exercise may augment the effects of cognitive remediation on improving cognitive functioning in severe mental illness. It has also been hypothesized that increases in cognitive functioning associated with adding exercise are mediated by increases in brain derived neurotrophic factor (BDNF). However, rigorous controlled trials are lacking.

METHODS

A randomized controlled trial was conducted to explore whether adding a 30-h aerobic exercise program over 10 weeks to an equally intensive cognitive remediation program (CR + E) improved cognitive functioning more than cognitive remediation alone (CR-Only). Thirty-four participants with schizophrenia or bipolar disorder were randomly assigned to CR + E or CR-Only, and cognitive functioning was assessed at baseline and post-treatment. Total and mature BDNF were measured in blood serum at baseline, Week-5 pre- and post-exercise, and Week-10 pre- and post-exercise.

RESULTS

Participants in both conditions had high levels of engagement in the interventions and improved significantly in cognitive functioning, but did not differ in amount of cognitive change. The groups also did not differ in changes in BDNF from pre-to post-exercise at Weeks 5 or 10, nor in resting BDNF levels. Exploratory analyses indicated that higher body mass index (BMI) significantly predicted attenuated improvement in cognitive functioning for both groups.

DISCUSSION

Exercise did not augment the effects of cognitive remediation in persons with severe mental illness, possibly because the cognitive remediation program resulted in strong gains in cognitive functioning. Moderate aerobic exercise does not appear to reliably increase BDNF levels in persons with severe mental illness. CLINICALTRIALS.

GOV IDENTIFIER

NCT02326389.

Aerobic exercise, cardiorespiratory fitness, and the human hippocampus

The hippocampus is particularly susceptible to neurodegeneration. Physical activity, specifically increasing cardiorespiratory fitness via aerobic exercise, shows promise as a potential method for mitigating hippocampal decline in humans. Numerous studies have now investigated associations between the structure and function of the hippocampus and engagement in physical activity. Still, there remains continued debate and confusion about the relationship between physical activity and the human hippocampus. In this review, we describe the current state of the physical activity and exercise literature as it pertains to the structure and function of the human hippocampus, focusing on four magnetic resonance imaging measures: volume, diffusion tensor imaging, resting-state functional connectivity, and perfusion. We conclude that, despite significant heterogeneity in study methods, populations of interest, and scope, there are consistent positive findings, suggesting a promising role for physical activity in promoting hippocampal structure and function throughout the lifespan.

In- and outpatient lifestyle interventions on diet and exercise and their effect on physical and psychological health: a systematic review and meta-analysis of randomised controlled trials in patients with schizophrenia spectrum disorders and first episode of psychosis

Patients with non-affective psychosis often lead unhealthy lifestyles. We performed a systematic review and meta-analysis on non-pharmacological RCTs for improvement of diet and physical activity in non-affective psychosis patients, including first-episode psychosis. A variety of outcomes was analysed, including metabolic, psychopathology, cognitive, functional and quality of life outcomes. Fifty-nine studies were included. An improvement in anthropometric measurements (BMI, weight, waist circumference) was observed post-intervention, persisting after follow-up. Post-intervention benefit was found also for psychotic symptoms severity (also persisting after follow-up), many cognitive domains and physical and global functioning and quality of life. Conversely, no effect was observed in relation to most blood metabolites, blood pressure and non-psychotic psychopathology and spontaneous physical activity. Improvement was generally larger for interventions including exercise, especially moderate/vigorous aerobic exercise, but follow-up maintenance was greater for psychotherapy interventions. Sensitivity analyses limited to chronic stages of psychosis and low risk of bias studies produced comparable results. Further studies are needed to design optimized interventions in this vulnerable population.

Incongruent Expression of Brain-Derived Neurotrophic Factor and Cortisol in Schizophrenia: Results from a Randomized Controlled Trial of Laughter Intervention

OBJECTIVE

Schizophrenia has been associated with dysfunction of the hypothalamic-pituitary-adrenal axis. Furthermore, alterations in neurotrophic factors might contribute to the pathogenesis of schizophrenia. We aimed to evaluate the effects of a simulated laughter intervention on the levels of cortisol and BDNF and to determine whether the effects associated with simulated laughter could be sustained after discontinuation of the intervention.

METHODS

In this randomized controlled study, patients with schizophrenia according to DSM-IV clinical criteria were randomly assigned to receive either 8-week-long simulated laughter intervention (n=32) or treatment-as-usual group (control group, n=27). The serum levels of BDNF and cortisol were measured at baseline, week 8, and four weeks after discontinuation (week 12) of the intervention program.

RESULTS

After an 8-week simulated laughter intervention, the laughter group had significantly higher levels of BDNF; however, four weeks after discontinuation of the intervention, the levels of BDNF significantly dropped. Interestingly, the levels of cortisol did not change significantly at week 8, but they were significantly elevated at week 12. The levels of BDNF and cortisol in the control group did not change significantly between week 0 and week 8.

CONCLUSION

These findings suggest that the simulated laughter intervention has an early effect on neurogenesis with a significant delayed effect on stress regulation in subjects with schizophrenia.

Strength training restores force-generating capacity in patients with schizophrenia

Patients with schizophrenia spectrum disorders have impaired skeletal muscle force-generating capacity (FGC) of the lower extremities, that is, one repetition maximum (1RM) and rapid force development, and poor functional performance. We therefore investigated whether 12 weeks of maximal strength training (MST) could (a) restore FGC and functional performance to the level of healthy references, (b) increase patient activation and quality of life, and (c) explore associations between symptom severity, defined daily dose of medication, illness duration, level of patient activation, and improvements in FGC and functional performance. Forty-eight outpatients were randomized to a training group (TG) or control group (CG). TG performed leg press MST 2 day/week at ~ 90% 1RM. The CG received two introductory training sessions and encouragement to train independently. Leg press 1RM, rapid force development, a battery of functional performance tests, Patient Activation Measure-13, and 36-Item Short Form Health Survey were tested. Healthy references performed baseline tests of FGC and functional performance. Thirty-six patients completed the study (TG: 17, CG: 19). TG improved 1RM (28%) and rapid force development (20%, both P < .01) to a level similar to healthy references, while no change was apparent in the CG. TG's improvement in rapid force development was negatively associated with defined daily dose of medication (r = -0.5, P = .05). Both TG and CG improved 30-second sit-to-stand test performance (P < .05) which was associated with improved rapid force development (r = 0.6, P < .05). In conclusion, 12 weeks of MST restored patients' lower extremity FGC to a level similar to healthy references and improved 30-second sit-to-stand test performance.

Cannabis use influence on peripheral brain-derived neurotrophic factor levels in antipsychotic-naïve first-episode psychosis

The objective of this study is to determine whether cannabis influences BDNF levels in patients with psychosis (FEP) and healthy volunteers (HV) to help understand the role of BDNF in psychosis. We assessed the association between BDNF and cannabis in a cohort of FEP antipsychotic-naïve patients and HV, whilst controlling for other potential confounding factors. 70 FEP drug-naive patients and 57 HV were recruited. A sociodemographic variable collection, structured clinical interview, weight and height measurement, substance use determination, and blood collection to determine BDNF levels by ELISA analysis were done. In FEP patients, cannabis use was associated with BDNF levels (high cannabis use was associated with lower BDNF levels). Moreover, cannabis use was statistically significantly associated with age (high use of cannabis was associated with younger age). In HV, no relationship between cannabis use and BDNF levels was observed. Otherwise, cannabis use was significantly associated with tobacco use, so that high cannabis users were also high tobacco users. This study showed a different association between cannabis use and BDNF levels in FEP patients compared with HV, particularly, with high doses of cannabis. These findings may help understand the deleterious effects of cannabis in some vulnerable individuals, as well as discrepancies in the literature.

Acute increases in brain-derived neurotrophic factor following high or moderate-intensity exercise is accompanied with better cognition performance in obese adults

The purpose of this study was to test if different intensities of aerobic exercise could influence abdominal fat, isoforms of BDNF and executive function. Twenty obese men (30.0 ± 5.4 years old; 34.4 ± 3.5 kg/m²) were randomized to moderate-intensity continuous training (MICT, n = 10) and high-intensity intermittent training (HIIT, n = 10) three times a week for 6 weeks, with isoenergetic energetic expenditure for each exercise session (~ 300 kcal) between conditions. Abdominal fat was assessed pre- and post-intervention; executive function (Coding subtest from BETA-III non-verbal intelligence test and Stroop Color and Word Test), concentrations of mBDNF and proBDNF were assessed in response to acute exercise pre- and post-intervention. Abdominal fat did not change in either group. There was a significant increase in mBDNF immediately after acute exercise in both groups before and after intervention. proBDNF did not present changes acutely nor after 6 weeks. Executive function presented a main effect of time at pre- and post-intervention time-points Stroop Word and Stroop Color and Coding subtest presented improved performance from pre- to post-acute exercise session, in both groups. In conclusion, executive function improvements and acute exercise session-induced increases in mBDNF concentration were found from pre- to post-exercise intervention similarly between MICT and HIIT in obese men.

The importance of physical fitness for the relationship of BDNF with obesity measures in young normal-weight adults

Aims

Brain derived neurotrophic factor (BDNF) is essential for cognitive function. It is also found in non-neuronal tissues with various regulatory actions, including metabolic. Physical fitness (PF) is associated with improved synthesis and secretion of BDNF and reduced obesity. However, the importance of PF for the relationship of BDNF with obesity has not been investigated. This study aims at examining the relationship of PF with BDNF and obesity in 174 young (age = 25.30 ± 9.2 years) healthy adults.

Main methods

Serum BDNF was evaluated using ELISA while obesity was determined using body weight (BW), BMI, and waist circumference (WC). Six minute walk distance (6MWD) test was used to estimate PF.

Key findings

Serum BDNF was greater (p = 0.000) in the participants with high (Hi6MWD) versus low (Lw6MWD) PF group. Additionally, 6MWD explained 6.8% of serum BDNF. Obesity measures were greater (p < 0.05) in the participants with low versus high BDNF. In regression analyses, serum BDNF explained 4.7% of BW (p = 0.004), 3.8% of BMI (p = 0.011), and 6.2% of WC (p = 0.001). However, when the participants were divided into Hi6MWD and Lw6MWD, BDNF explained 8.2% of BW (p = 0.009), 6.0% of BMI (p = 0.03), and 7.0% of WC (p = 0.013), only in the Hi6MWD, but not in the Lw6MWD (p > 0.05) groups.

Significance

The finding confirms the relationship of BDNF with obesity. Additionally, it further suggests the importance of PF level to this relationship among young adults. Future studies are needed to confirm these findings.

Is there an association between cardiorespiratory fitness and stage of illness in psychotic disorders? A systematic review and meta-analysis

BACKGROUND

Clinical staging models describe where an individual exists on a continuum from asymptomatic at-risk states (Stage 0) through to established late-stage disease (Stage 4). We applied this framework to systematically assess evidence for any associations between objectively assessed cardiorespiratory fitness (CRF) and stage of psychosis.

METHOD

Nine electronic databases were searched for relevant publications from inception until October 31, 2019. Pooled effect sizes (Hedges' g and 95% confidence intervals (95% CI)) were estimated for differences in CRF for studies that reported mean oxygen uptake (max, peak, or predicted VO₂ in ml/kg/min).

RESULTS

Thirty-eight studies were eligible. Findings indicated that suboptimal CRF can be present at Stages 0 and 1. Meta-analyses of 22 studies demonstrated that CRF was significantly reduced in individuals classified between Stages 1 and 4 compared with matched or general population controls (g = -0.93; 95% CI -1.14, -0.71). Mean VO₂ was decreased by 28% in Stage 4 compared with Stage 1 (34.1 vs. 24.66 ml/kg/min); the largest effect size for CRF reduction was reported between Stages 2 and 3 (g = -1.16; 95% CI -1.31, -1.03).

CONCLUSIONS

Although not identifying direct causal links between clinical stage and CRF, using this framework may enhance understanding of co-associations between mental and physical health markers across the entire spectrum of psychosis. Limitations include lack of research on CRF in Stages 0 and 1 alongside problems determining stage in some studies. However, impaired CRF is reported in emerging psychosis, supporting calls that early intervention programmes should address both mental and physical wellbeing.

Exercise and Schizophrenia

Schizophrenia is a psychiatric disorder characterized by distortions of thinking and perception, with no strictly pathognomonic symptoms that can be divided into positive, negative, and cognitive symptom domains. People with schizophrenia have, between others, a reduced life expectancy and cardiorespiratory and muscular fitness and increased risk of cardiovascular disease, metabolic syndrome, obesity, hypertension, and hyperlipidemia compared to the general population. Furthermore, the economic burden of mental disorders including schizophrenia is evident and it is expected to increase to more than double by 2030. Therefore, reducing the growing burden of mental disorders such as schizophrenia should be a health priority. Improved prevention and treatment are two key factors that may reduce the burden of schizophrenia. Pharmacological- and psychotherapy-based interventions have been traditionally considered for treating schizophrenia disorders; however, there is an increasing amount of scientific evidence confirming that physical activity and physical exercise should be highly considered in prevention and treatment of schizophrenia disorders. In this chapter, we aim to summarize and discuss the research progress of physical activity and exercise in prevention and treatment of schizophrenia disorder. Specifically, we summarized and discussed the research progress of the prognostic use of physical activity for incident schizophrenia; the importance of other outcomes typically improved by physical activity/exercise such as obesity and fitness (cardiorespiratory and muscular fitness) for future schizophrenia; the research progress of the evidence of the benefits of exercise in people with schizophrenia disorders differentiating between effects of exercise on varied health outcomes, cognitive functioning, and cardiorespiratory fitness; and finally the clinical practice recommendations.

Effects of Resistance Exercise on Cerebral Redox Regulation and Cognition: An Interplay Between Muscle and Brain

This review highlighted resistance training as an important training type for the brain. Most studies that use physical exercise for the prevention or treatment of neurodegenerative diseases have focused on aerobic physical exercise, revealing different behavioral, biochemical, and molecular effects. However, recent studies have shown that resistance training can also significantly contribute to the prevention of neurodegenerative diseases as well as to the maintenance, development, and recovery of brain activities through specific neurochemical adaptations induced by the training. In this scenario we observed the results of several studies published in different journals in the last 20 years, focusing on the effects of resistance training on three main neurological aspects: Neuroprotective mechanisms, oxidative stress, and cognition. Systematic database searches of PubMed, Web of Science, Scopus, and Medline were performed to identify peer-reviewed studies from the 2000s. Combinations of keywords related to brain disease, aerobic/resistance, or strength physical exercise were used. Other variables were not addressed in this review but should be considered for a complete understanding of the effects of training in the brain.

Exercise, spinogenesis and cognitive functions

Exercise training improves mental and cognitive functions by enhancing neurogenesis and neuroprotection. Recent studies suggest the facilitation of spinogenesis across different brain regions including hippocampus and cerebral cortex by physical activity. In this article we will summarize major findings for exercise effects on synaptogenesis and spinogenesis, in order to provide mechanisms for exercise intervention of both psychiatric diseases and neurodegenerative disorders. We will also revisit major findings for molecular mechanism governing exercise-related spinogenesis, and will discuss the screening for novel factors, or exerkines, whose levels are correlated with endurance training and affect neural plasticity. We believe that further studies focusing on the molecular mechanism of exercise-mediate spinogenesis should benefit the optimization of exercise therapy in clinics and the evaluation of treatment efficiency using specific biomarkers.

Neurobiological effects of aerobic exercise, with a focus on patients with schizophrenia

Schizophrenia is a severe neuropsychiatric disease that is associated with neurobiological alterations in multiple brain regions and peripheral organs. Negative symptoms and cognitive deficits are present in about half of patients and are difficult to treat, leading to an unfavorable functional outcome. To investigate the impact of aerobic exercise on various neurobiological parameters, we conducted a narrative review. Add-on aerobic exercise was shown to be effective in improving negative and general symptoms, cognition, global functioning, and quality of life in schizophrenia patients. Based on findings in healthy individuals and animal models, this qualitative review gives an overview of different lines of evidence on how aerobic exercise impacts brain structure and function and molecular mechanisms in patients with schizophrenia and how its effects could be related to clinical and functional outcomes. Structural magnetic resonance imaging studies showed a volume increase in the hippocampus and cortical regions in schizophrenia patients and healthy controls after endurance training. However, results are inconsistent and individual risk factors may influence neuroplastic processes. Animal studies indicate that alterations in epigenetic mechanisms and synaptic plasticity are possible underlying mechanisms, but that differentiation of glial cells, angiogenesis, and possibly neurogenesis may also be involved. Clinical and animal studies also revealed effects of aerobic exercise on the hypothalamus-pituitary-adrenal axis, growth factors, and immune-related mechanisms. Some findings indicate effects on neurotransmitters and the endocannabinoid system. Further research is required to clarify how individual risk factors in schizophrenia patients mediate or moderate the neurobiological effects of exercise on brain and cognition. Altogether, aerobic exercise is a promising candidate in the search for pathophysiology-based add-on interventions in schizophrenia.

Short-time high-intensity exercise increases peripheral BDNF in a physical fitness-dependent way in healthy men

BDNF is associated with brain health and positively modulated by exercise; however, the influence of physical fitness status on BDNF is incipient. This study investigated the BDNF response after acute-exercise sessions performed at low, moderate, and high intensities and the relationship between physical fitness status and BDNF response. Twenty-eight men, divided according to physical fitness status (<50th or >50th percentile for VO_2max), performed three randomised acute exercise sessions at low (90% of VT1), moderate (midpoint between VT1-VT2), and high (midpoint between VT2-W_max) intensities until exhaustion or for up to 60 min. Lactate and BDNF were determined pre and post-exercises. For BDNF, there were main effects of time (p = 0.003) and interaction (p < 0.001), showing an increase post high-intensity exercise (p < 0.001). Changes in BDNF presented differences between conditions (p < 0.001) with greater increase in high-intensity compared with the others (p = 0.003). For lactate, there were main effects of time (p < 0.001), condition (p < 0.001), and interaction (p < 0.001) with greater concentration in high-intensity. High-intensity exercise exhibited inverse correlation between the changes in BDNF and lactate (r=-0.38, p = 0.044). There was significant correlation between BDNF and VO_2max for moderate (r = -0.57, p = 0.002) and a trend for high-intensity condition (r = -0.37, p = 0.050) and when evaluating BDNF according to physical fitness level, it was observed that subjects with lower physical fitness levels had greater increases in BDNF in short-time high-intensity exercise (p = 0.041). In conclusion, short-time high-intensity exercise seems to be more efficient in increasing BDNF concentration, and physical fitness level influences this response, as healthy individuals with lower physical fitness levels were more responsive.

Brain-Derived Neurotrophic Factor in Brain Disorders: Focus on Neuroinflammation

Brain-derived neurotrophic factor (BDNF) is one of the most studied neurotrophins in the healthy and diseased brain. As a result, there is a large body of evidence that associates BDNF with neuronal maintenance, neuronal survival, plasticity, and neurotransmitter regulation. Patients with psychiatric and neurodegenerative disorders often have reduced BDNF concentrations in their blood and brain. A current hypothesis suggests that these abnormal BDNF levels might be due to the chronic inflammatory state of the brain in certain disorders, as neuroinflammation is known to affect several BDNF-related signaling pathways. Activation of glia cells can induce an increase in the levels of pro- and antiinflammatory cytokines and reactive oxygen species, which can lead to the modulation of neuronal function and neurotoxicity observed in several brain pathologies. Understanding how neuroinflammation is involved in disorders of the brain, especially in the disease onset and progression, can be crucial for the development of new strategies of treatment. Despite the increasing evidence for the involvement of BDNF and neuroinflammation in brain disorders, there is scarce evidence that addresses the interaction between the neurotrophin and neuroinflammation in psychiatric and neurodegenerative diseases. This review focuses on the effect of acute and chronic inflammation on BDNF levels in the most common psychiatric and neurodegenerative disorders and aims to shed some light on the possible biological mechanisms that may influence this effect. In addition, this review will address the effect of behavior and pharmacological interventions on BDNF levels in these disorders.

Taekwondo Enhances Cognitive Function as a Result of Increased Neurotrophic Growth Factors in Elderly Women

The purpose of this study was to investigate the effects of regular taekwondo (TKD) training on physical fitness, neurotrophic growth factors, cerebral blood flow (CBF) velocity, and cognitive function in elderly women. Thirty-seven women aged 65 or older were randomly assigned to either TKD (n = 19) or control (n = 18) group. TKD training was performed at 50⁻80% maximum heart rate (HRmax) for 60 min, five times per week for 16 weeks. All participants underwent the following examinations before and after the intervention: Senior Fitness Test; serum levels of neurotrophic growth factors, including brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF), and insulin-like growth factor-1 (IGF-1); systolic, diastolic, and mean blood flow velocity and pulsatility index of the middle cerebral artery using Doppler ultrasonography; Mini-Mental State Examination for dementia screening (MMSE-DS); and Stroop Color and Word Test (word, color, and color-word). In the TKD group, lower body strength and flexibility, aerobic endurance levels, BDNF, VEGF, and IGF-1 serum levels as well as the color-word test scores were significantly increased after as compared to before the intervention (p < 0.05). No statistically significant differences were found in cerebral blood flow velocities and the MMSE-DS score (p > 0.05). These findings suggest that regular TKD training may be effective in improving not only fitness but also cognitive function in elderly women. The latter effect may be due to increased neurotrophic growth factor levels.

Exercise as a Treatment for Schizophrenia: A Review

Schizophrenia is a mental disorder that is characterized by progressive cognitive impairment in areas of attention, working memory, and executive functioning. Although no clear etiology of schizophrenia has been discovered, many factors have been identified that contribute to the development of the disease, such as neurotransmitter alterations, decreased synaptic plasticity, and diminished hippocampal volume. Historically, antipsychotic medications have targeted biochemical alterations in the brains of patients with schizophrenia but have been ineffective in alleviating cognitive and hippocampal deficits. Other modalities, such as exercise therapy, have been proposed as adjuvant or primary therapy options. Exercise therapy has been shown to improve positive and negative symptoms, quality of life, cognition, and hippocampal plasticity, and to increase hippocampal volume in the brains of patients with schizophrenia. This article will briefly review the clinical signs, symptoms and proposed etiologies of schizophrenia, and describe the current understanding of exercise programs as an effective treatment in patients with the disease.

The neurobiological hypothesis of neurotrophins in the pathophysiology of schizophrenia: A meta-analysis

BACKGROUND

Schizophrenia is associated with patterns of aberrant neurobiological circuitry. The disease complexity is mirrored by multiple biological interactions known to contribute to the disease pathology. One potential contributor is the family of neurotrophins which are proteins involved in multiple functional processes in the nervous system, with crucial roles in neurodevelopment, synaptogenesis and neuroplasticity. With these roles in mind, abnormal neurotrophin profiles have been hypothesized to contribute to the pathology of schizophrenia.

METHODS

We performed a systematic review and a meta-analysis to scrutinize the neurobiological hypothesis of neurotrophins in schizophrenia, examining the correlation between peripheral levels of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin-3 (NT-3) and neurotrophin 4/5 (NT-4/5) associated with schizophrenia.

RESULTS

Fifty-two studies were reviewed and twenty-two studies were included in this meta-analysis. Using a random effects model, we confirmed that decreased levels of neurotrophins (BDNF, NGF and NT-4/5) were associated with schizophrenia (Hedges's g = -0.846; SE = 0.058; 95% confidence interval: -0.960 to -0.733; Z-value = -14.632; p-value = 0.000). Subgroup analysis indicated that neurotrophin levels are significantly decreased in both medicated and drug-näive patients. Meta-regression of continuous variables such as mean age, duration of illness and PANSS total score did not show significant effects (p > 0.05) in relation to neurotrophins levels.

DISCUSSION

We confirm that decreased peripheral neurotrophin levels are significantly associated with schizophrenia, thereby confirming the neurobiological hypothesis of neurotrophins in schizophrenia. Low levels of neurotrophins in peripheral blood of patients with schizophrenia may explain, in part, the pathophysiology of schizophrenia.

[Physical activity in patients with schizophrenia: From neurobiology to clinical benefits]

Schizophrenia is a severe chronic mental disorder that mainly manifests by positive symptoms, negative symptoms, disorganized behavior and thought and cognitive impairments. Taken together, these symptoms have substantial impact on quality of life, well-being and functional outcome. Patients with schizophrenia have dramatically higher levels of cardiovascular and metabolic morbidity than the general population due to poor physical fitness and to sedentary lifestyle. They have a reduced life expectancy, and an excess mortality being two or three times more than that in the general population. Moreover, despite major therapeutic advances in the overall management of these patients, some symptomatic dimensions, and more specifically the negative and cognitive ones, remain to be resistant to the usual pharmacological approaches. Moreover, antipsychotics can also reinforce the global cardiovascular risk due to side effects and low neurometabolic tolerance. The benefits of physical activity on health are now well described in the general population and in many medical diseases. More recently, physical activity has also found its place as an adjuvant therapy in severe mental illnesses, particularly in schizophrenia. In the literature physical activity programs, in addition to pharmacological treatments, appear to be feasible in patients and improve both physical and mental health as well as functional outcome. Clinical benefits of physical activity would be underpinned by biological and cerebral mechanisms, which remain unclear. In this review, we propose to present a state of the art and to present an update of the interests of physical activity in the management of patients with schizophrenia. We emphasize the clinical benefits of physical activity regarding the different symptomatic dimensions and its impact specifically on cognitive deficits. Finally, we describe the various underlying pathophysiological mechanisms in particular in the neurobiological, cerebral and physiological fields. We then discuss the barriers, facilitators and motivating factors towards physical activity to enhance health promotion initiatives, to optimize resource allocation when delivering physical activity programs in clinical practice, and to maximize physical activity participation. Physical activity appears to be an original and novel adjunctive therapeutic approach in the management of patients with schizophrenia and would both reduce schizophrenic symptoms and act like pro-cognitive therapy, improve quality of life and long-term functioning in daily life and reduce cardiovascular comorbidities. However, efforts are still needed to increase the motivating factors and adherence towards physical activity participation for people with schizophrenia.

Exercise as an intervention for first-episode psychosis: a feasibility study

AIM

Exercise can improve psychiatric symptoms, neurocognitive functioning and physical health in schizophrenia. However, the effects in early psychosis have not been explored. This study aimed to assess the feasibility of an exercise intervention for early psychosis and to determine if it was associated with changes in physical and mental health.

METHODS

Thirty-one patients with first-episode psychosis (FEP) were recruited from early intervention services to a 10-week exercise intervention. The intervention group received individualized training programmes, aiming to achieve ≥90 min of moderate-to-vigorous activity each week, using exercise programmes tailored to individual preferences and needs. A comparison FEP sample from the same services (n = 7) received treatment as usual.

RESULTS

Rates of consent and retention in the exercise group were 94% and 81%, respectively. Participants achieved an average of 107 min of moderate-to-vigorous exercise per week. Positive and Negative Syndrome Scale total scores reduced by 13.3 points after 10 weeks of exercise, which was significantly greater than the treatment as usual comparison group (P = 0.010). The greatest differences were observed in negative symptoms, which reduced by 33% in the intervention group (P = 0.013). Significant improvements were also observed in psychosocial functioning and verbal short-term memory. Increases in cardiovascular fitness and processing speed were positively associated with the amounts of exercise achieved by participants.

CONCLUSION

Individualized exercise training could provide a feasible treatment option for improving symptomatic, neurocognitive and metabolic outcomes in FEP.

On the Run for Hippocampal Plasticity

Accumulating research in rodents and humans indicates that exercise benefits brain function and may prevent or delay onset of neurodegenerative conditions. In particular, exercise modifies the structure and function of the hippocampus, a brain area important for learning and memory. This review addresses the central and peripheral mechanisms underlying the beneficial effects of exercise on the hippocampus. We focus on running-induced changes in adult hippocampal neurogenesis, neural circuitry, neurotrophins, synaptic plasticity, neurotransmitters, and vasculature. The role of peripheral factors in hippocampal plasticity is also highlighted. We discuss recent evidence that systemic factors released from peripheral organs such as muscle (myokines), liver (hepatokines), and adipose tissue (adipokines) during exercise contribute to hippocampal neurotrophin and neurogenesis levels, and memory function. A comprehensive understanding of the body-brain axis is needed to elucidate how exercise improves hippocampal plasticity and cognition.

A systematic review of trials investigating strength training in schizophrenia spectrum disorders

This systematic review analyzed strength training (ST) in patients with schizophrenia. Two independent reviewers searched PubMed and CENTRAL. Only two studies reported on the effects of isolated ST. ST with a single exercise did not improve psychopathology but walking performance. ST for several large muscle groups significantly improved muscle strength and psychopathology. To date, no treatment recommendations can be made for ST. Consistent with recommendations for healthy people combined strength and endurance training can be recommended for schizophrenia. For higher transparency regarding trainings aspects, we recommend for future studies to use the sport science checklist proposed in this paper.

The pro-cognitive mechanisms of physical exercise in people with schizophrenia

Schizophrenia is associated with pervasive cognitive deficits which are unresponsive to antipsychotic medications. Physical exercise has been shown to improve cognitive functioning in people with schizophrenia, although the mechanisms for this are unclear. We conducted a systematic review of all exercise intervention studies which reported changes in brain structure, connectivity or peripheral biomarkers which could underlie cognitive improvements from exercise in schizophrenia. An electronic database search was conducted on 22 September 2016 using keywords relevant to exercise and neurocognition in schizophrenia. The search returned 2342 articles. Sixteen were eligible for inclusion, reporting data from 14 independent trials of 423 patients with schizophrenia. Seven studies used neuroimaging to examine the impact of exercise on brain structure and connectivity in schizophrenia, whereas seven other studies examined peripheral biomarkers to assess the effects of exercise. Imaging studies collectively indicated that exercise can increase brain volume in people with schizophrenia, although the regions which responded to exercise varied across studies. Most biomarker studies assessed the effects of exercise on serum levels of BDNF. Several studies found significant increases from exercise along with positive correlations between BDNF and cognitive enhancements (indicating a mechanistic link), although other studies did not observe this relationship. In conclusion, the cognitive benefits of exercise in schizophrenia may be due to exercise stimulating neurogenesis, perhaps by up-regulating BDNF, although current evidence is insufficient to draw definitive conclusions. Further exploration of the pro-cognitive mechanisms of exercise in schizophrenia would inform the development of optimal interventions for reducing cognitive impairments in this population. Linked Articles This article is part of a themed section on Pharmacology of Cognition: a Panacea for Neuropsychiatric Disease? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.19/issuetoc.

Exercise Treatments for Psychosis: A Review

Schizophrenia is a devastating mental illness that has profound effects on a person's health and quality of life. Exercise represents a promising new treatment option that may supplement current psychosocial and pharmacological interventions for psychosis. A large body of work suggests that exercise can improve cardio-metabolic and health behavior and facilitate neurogenesis in areas of the brain that are notably impacted by psychosis. Recent efforts to incorporate exercise as either stand-alone or adjunctive treatment for individuals with schizophrenia range from yoga and light stretching to moderately intense walking, bike riding, or team sports. These interventions suggest that moderately intense exercise may be beneficial for improving both positive and negative symptomatology, cognition and functioning. Indeed, exercise may be beneficial for decreasing risk factors for a wide range of health problems often observed in patients with schizophrenia, including weight gain and metabolic syndrome as well as tobacco and substance use. Given the positive results from interventions in schizophrenia patients, there is an impetus for incorporating exercise in the early stages of the disorder. Notably, individuals at ultrahigh risk (UHR) for psychosis report more sedentary behavior and perceive less benefit from exercise; interventions prior to the onset of the disorder may be helpful for increasing health behaviors, perhaps delaying or preventing the onset of psychosis. Taken together, for individuals with psychosis, exercise may provide holistic benefits for the neural to the social impairments.

Brain-derived neurotrophic factor (BDNF) serum basal levels is not affected by power training in mobility-limited older adults - A randomized controlled trial

Brain-derived neurotrophic factor (BDNF) is a potential important factor involved in neuroplasticity, and may be a mediator for eliciting adaptations in neuromuscular function and physical function in older individuals following physical training. As power training taxes the neural system to a very high extent, it may be particularly effective in terms of eliciting increases in systemic BDNF levels. We examined the effects of 12weeks of power training on mature BDNF (mBDNF) and total BDNF (tBDNF) in mobility-limited older adults from the Healthy Ageing Network of Competence (HANC) study. We included 47 older men and women: n=22 in the training group (TG: progressive high intensity power training, 2 sessions per week; age 82.7±5.4years, 55% women) and n=25 in the control group (CG: no interventions; age 82.2±4.5years, 76% women). Following overnight fasting, basal serum levels of mBDNF and tBDNF were assessed (human ELISA kits) at baseline and post-intervention. At baseline, mBDNF and tBDNF levels were comparable in the two groups, TG and CG. Post-intervention, no significant within-group or between-group changes were observed in mBDNF or tBDNF. Moreover, when divided into responder tertiles based upon changes in mBDNF and tBDNF (i.e. decliners, maintainers, improvers), respectively, comparable findings were observed for TG and CG. Altogether, basal systemic levels of serum mBDNF and tBDNF are not affected in mobility-limited older adults following 12-weeks of power training, and do not appear to be a major mechanistic factor mediating neuroplasticity in mobility-limited older adults.

APOEε4 impacts up-regulation of brain-derived neurotrophic factor after a six-month stretch and aerobic exercise intervention in mild cognitively impaired elderly African Americans: A pilot study

Possession of the Apolipoprotein E (APOE) gene ε4 allele is the most prevalent genetic risk factor for late onset Alzheimer's disease (AD). Recent evidence suggests that APOE genotype differentially affects the expression of brain-derived neurotrophic factor (BDNF). Notably, aerobic exercise-induced upregulation of BDNF is well documented; and exercise has been shown to improve cognitive function. As BDNF is known for its role in neuroplasticity and survival, its upregulation is a proposed mechanism for the neuroprotective effects of physical exercise. In this pilot study designed to analyze exercise-induced BDNF upregulation in an understudied population, we examined the effects of APOEε4 (ε4) carrier status on changes in BDNF expression after a standardized exercise program. African Americans, age 55years and older, diagnosed with mild cognitive impairment participated in a six-month, supervised program of either stretch (control treatment) or aerobic (experimental treatment) exercise. An exercise-induced increase in VO₂Max was detected only in male participants. BDNF levels in serum were measured using ELISA. Age, screening MMSE scores and baseline measures of BMI, VO₂Max, and BDNF did not differ between ε4 carriers and non-ε4 carriers. A significant association between ε4 status and serum BDNF levels was detected. Non-ε4 carriers showed a significant increase in BDNF levels at the 6month time point while ε4 carriers did not. We believe we have identified a relationship between the ε4 allele and BDNF response to physiologic adaptation which likely impacts the extent of neuroprotective benefit gained from engagement in physical exercise. Replication of our results with inclusion of diverse racial cohorts, and a no-exercise control group will be necessary to determine the scope of this association in the general population.

The Efficacy of Non-Pharmacological Interventions on Brain-Derived Neurotrophic Factor in Schizophrenia: A Systematic Review and Meta-Analysis

Several studies have investigated the relationship between non-pharmacological interventions (NPIs) and peripheral brain-derived neurotrophic factor (BDNF) in schizophrenia patients. We conducted a systematic review and meta-analysis to review the efficacy of NPIs on peripheral serum and plasma BDNF in subjects with schizophrenia (including schizoaffective disorder). Meta-analyses were conducted to examine the effects of NPIs on blood BDNF levels by using the standardized mean differences (SMDs) between the intervention groups and controls. In total, six randomized controlled trials with 289 participants were included. Of them, five studies used exercise, physical training or diet products. One study used cognitive training. Overall, the BDNF levels in the NPI group increased significantly compared with the control groups (SMD = 0.95, 95% confidence interval (CI) = 0.07 to 1.83, p = 0.03). Subgroup analyses indicated beneficial effects of a non-exercise intervention on peripheral BDNF levels (SMD = 0.41, 95% CI = 0.08 to 0.74, p = 0.01). Meta-regression analyses showed that the completion rate influenced the variation in SMD (p = 0.01). Despite insufficient evidence to draw a conclusion, our results suggest that use of NPIs as adjunctive treatments, specifically non-exercise interventions, may affect positively serum or plasma BDNF in patients with schizophrenia.

A Bidirectional Relationship between Executive Function and Health Behavior: Evidence, Implications, and Future Directions

Physically active lifestyles and other health-enhancing behaviors play an important role in preserving executive function into old age. Conversely, emerging research suggests that executive functions facilitate participation in a broad range of healthy behaviors including physical activity and reduced fatty food, tobacco, and alcohol consumption. They do this by supporting the volition, planning, performance monitoring, and inhibition necessary to enact intentions and override urges to engage in health damaging behavior. Here, we focus firstly on evidence suggesting that health-enhancing behaviors can induce improvements in executive function. We then switch our focus to findings linking executive function to the consistent performance of health-promoting behaviors and the avoidance of health risk behaviors. We suggest that executive function, health behavior, and disease processes are interdependent. In particular, we argue that a positive feedback loop may exist whereby health behavior-induced changes in executive function foster subsequent health-enhancing behaviors, which in turn help sustain efficient executive functions and good health. We conclude by outlining the implications of this reciprocal relationship for intervention strategies, the design of research studies, and the study of healthy aging.

Endurance training in patients with schizophrenia and healthy controls: differences and similarities

The aims were to examine the feasibility of and adaptations to endurance training in persons diagnosed with schizophrenia and to address the question whether the principles and beneficial effects of endurance training established in the healthy population apply also to patients with schizophrenia. In this controlled interventional study, 22 patients with schizophrenia and 22 healthy controls performed a standardized aerobic endurance training on bicycle ergometers over 12 weeks. Another group of 21 patients with schizophrenia played table soccer. Endurance capacity was measured with incremental cycle ergometry before and after the intervention and 3 months later. A specific set of outcome parameters was defined. The training stimuli can be assumed to be similar in both endurance groups. Endurance capacity improved significantly in the endurance groups, but not in the table soccer group. Patients and healthy controls showed comparable adaptations to endurance training, as assessed by physical working capacity and maximal achieved power. Differences were found in changes of performance at a lactate concentration of 3 mmol/l. Endurance training was feasible and effective in both groups. The principles and types of training that are usually applied to healthy controls need to be verified in patients with schizophrenia. Nevertheless, patients benefited from endurance training in terms of improvement of endurance capacity and reduction in the baseline deficit in comparison with healthy controls. Therefore, endurance training should be implemented in future therapy programs. These programs need to pay special attention to the differences between patients with schizophrenia and healthy controls.

Aerobic Exercise as a Tool to Improve Hippocampal Plasticity and Function in Humans: Practical Implications for Mental Health Treatment

Aerobic exercise (AE) has been widely praised for its potential benefits to cognition and overall brain and mental health. In particular, AE has a potent impact on promoting the function of the hippocampus and stimulating neuroplasticity. As the evidence-base rapidly builds, and given most of the supporting work can be readily translated from animal models to humans, the potential for AE to be applied as a therapeutic or adjunctive intervention for a range of human conditions appears ever more promising. Notably, many psychiatric and neurological disorders have been associated with hippocampal dysfunction, which may underlie the expression of certain symptoms common to these disorders, including (aspects of) cognitive dysfunction. Augmenting existing treatment approaches using AE based interventions may promote hippocampal function and alleviate cognitive deficits in various psychiatric disorders that currently remain untreated. Incorporating non-pharmacological interventions into clinical treatment may also have a number of other benefits to patient well being, such as limiting the risk of adverse side effects. This review incorporates both animal and human literature to comprehensively detail how AE is associated with cognitive enhancements and stimulates a cascade of neuroplastic mechanisms that support improvements in hippocampal functioning. Using the examples of schizophrenia and major depressive disorder, the utility and implementation of an AE intervention to the clinical domain will be proposed, aimed to reduce cognitive deficits in these, and related disorders.

Enhancing Cognitive Training Through Aerobic Exercise After a First Schizophrenia Episode: Theoretical Conception and Pilot Study

Cognitive training (CT) and aerobic exercise have separately shown promise for improving cognitive deficits in schizophrenia. Aerobic exercise releases brain-derived neurotrophic factor, which promotes synaptic plasticity and neurogenesis. Thus, aerobic exercise provides a neurotrophic platform for neuroplasticity-based CT. The combination of aerobic exercise and CT may yield more robust effects than CT alone, particularly in the initial course of schizophrenia. In a pilot study, 7 patients with a recent onset of schizophrenia were assigned to Cognitive Training & Exercise (CT&E) and 9 to CT alone for a 10-week period. Posit Science programs were used for CT. Neurocognitive training focused on tuning neural circuits related to perceptual processing and verbal learning and memory. Social cognitive training used the same learning principles with social and affective stimuli. Both groups participated in these training sessions 2d/wk, 2h/d. The CT&E group also participated in an aerobic conditioning program for 30 minutes at our clinic 2d/wk and at home 2d/wk. The effect size for improvement in the MATRICS Consensus Cognitive Battery Overall Composite score for CT&E patients relative to CT patients was large. Functional outcome, particularly independent living skills, also tended to improve more in the CT&E than in the CT group. Muscular endurance, cardiovascular fitness, and diastolic blood pressure also showed relative improvement in the CT&E compared to the CT group. These encouraging pilot study findings support the promise of combining CT and aerobic exercise to improve the early course of schizophrenia.

Increased serum brain-derived neurotrophic factor levels following electroconvulsive therapy or antipsychotic treatment in patients with schizophrenia

BACKGROUND

Many schizophrenia patients experience residual symptoms even after treatment. Electroconvulsive therapy (ECT) is often used in medication-resistant schizophrenia patients when pharmacologic interventions have failed; however, the mechanism of action is unclear. Brain-derived neurotrophic factor (BDNF) levels are reduced in drug-naive, first-episode schizophrenia and are increased by antipsychotic treatment. We tested the hypothesis that ECT increases serum BDNF levels by measuring BDNF concentrations in schizophrenia patients before and after they received ECT.

METHODS

A total of 160 patients with schizophrenia were examined. The ECT group (n=80) was treated with antipsychotics and ECT (eight to 10 sessions administered every other day). The drug therapy group (n=80) received only antipsychotic treatment. A control group (n=77) was recruited that served as the baseline for comparison.

RESULTS

Baseline serum BDNF level in ECT group was lower than in controls (9.7±2.1 vs. 12.4±3.2ng/ml; P<0.001), but increased after ECT, such that there was no difference between the two groups (11.9±3.3 vs. 12.4±3.2ng/ml; P=0.362). There was no correlation between patients' Positive and Negative Syndrome Scale (PANSS) score and serum BDNF level before ECT; however, a negative correlation was observed after ECT (total: r=-0.692; P<0.01). From baseline to remission after ECT, serum BDNF level increased (P<0.001) and their PANSS score decreased (P<0.001). Changes in BDNF level (2.21±4.10ng/ml) and PANSS score (28.69±14.96) were positively correlated in the ECT group (r=0.630; P<0.01).

CONCLUSIONS

BDNF level was lower in schizophrenia patients relative to healthy controls before ECT and medication. BDNF level increased after ECT and medication, and its longitudinal change was associated with changes in patients' psychotic symptoms. These results indicate that BDNF mediates the antipsychotic effects of ECT.

Exercise Improves Clinical Symptoms, Quality of Life, Global Functioning, and Depression in Schizophrenia: A Systematic Review and Meta-analysis

BACKGROUND

Physical exercise may be valuable for patients with schizophrenia spectrum disorders as it may have beneficial effect on clinical symptoms, quality of life and cognition.

METHODS

A systematic search was performed using PubMed (Medline), Embase, PsychInfo, and Cochrane Database of Systematic Reviews. Controlled and uncontrolled studies investigating the effect of any type of physical exercise interventions in schizophrenia spectrum disorders were included. Outcome measures were clinical symptoms, quality of life, global functioning, depression or cognition. Meta-analyses were performed using Comprehensive Meta-Analysis software. A random effects model was used to compute overall weighted effect sizes in Hedges' g.

RESULTS

Twenty-nine studies were included, examining 1109 patients. Exercise was superior to control conditions in improving total symptom severity (k = 14, n = 719: Hedges' g = .39, P < .001), positive (k = 15, n = 715: Hedges' g = .32, P < .01), negative (k = 18, n = 854: Hedges' g = .49, P < .001), and general (k = 10, n = 475: Hedges' g = .27, P < .05) symptoms, quality of life (k = 11, n = 770: Hedges' g = .55, P < .001), global functioning (k = 5, n = 342: Hedges' g = .32, P < .01), and depressive symptoms (k = 7, n = 337: Hedges' g = .71, P < .001). Yoga, specifically, improved the cognitive subdomain long-term memory (k = 2, n = 184: Hedges' g = .32, P < .05), while exercise in general or in any other form had no effect on cognition.

CONCLUSION

Physical exercise is a robust add-on treatment for improving clinical symptoms, quality of life, global functioning, and depressive symptoms in patients with schizophrenia. The effect on cognition is not demonstrated, but may be present for yoga.

Aerobic Exercise in People with Schizophrenia: Neural and Neurocognitive Benefits

Schizophrenia is characterized by extensive neurocognitive deficits, which are linked to greater disability, poorer functional outcome, and have been suggested to impact daily functioning more than clinical symptoms. Aerobic exercise (AE) has emerged as a potential intervention. This review examines the impact of AE on brain structure and function along with neurocognitive performance in individuals with schizophrenia. Preliminary evidence indicates that AE can increase hippocampal volume and cortical thickness, in addition to exerting a neuroprotective effect against hippocampal volume decrease and cortical thinning. There is also evidence that AE is able to significantly increase serum brain-derived neurotrophic factor (BDNF) levels, which are implicated in neurogenesis, neuroplasticity, and cognitive improvement. Finally, evidence suggests that AE plays a significant role in improving overall cognition, including improvements in processing speed, working memory, and visual learning. The authors discuss the implications of the findings and provide recommendations for future research and areas of inquiry.

Physical activity and exercise attenuate neuroinflammation in neurological diseases

Major depressive disorder (MDD), schizophrenia (SCH), Alzheimer's disease (AD), and Parkinson's disease (PD) are devastating neurological disorders, which increasingly contribute to global morbidity and mortality. Although the pathogenic mechanisms of these conditions are quite diverse, chronic neuroinflammation is one underlying feature shared by all these diseases. Even though the specific root causes of these diseases remain to be identified, evidence indicates that the observed neuroinflammation is initiated by unique pathological features associated with each specific disease. If the initial acute inflammation is not resolved, a chronic neuroinflammatory state develops and ultimately contributes to disease progression. Chronic neuroinflammation is characterized by adverse and non-specific activation of glial cells, which can lead to collateral damage of nearby neurons and other glia. This misdirected neuroinflammatory response is hypothesized to contribute to neuropathology in MDD, SCH, AD, and PD. Physical activity (PA), which is critical for maintenance of whole body and brain health, may also beneficially modify neuroimmune responses. Since PA has neuroimmune-modifying properties, and the common underlying feature of MDD, SCH, AD, and PD is chronic neuroinflammation, we hypothesize that PA could minimize brain diseases by modifying glia-mediated neuroinflammation. This review highlights current evidence supporting the disease-altering potential of PA and exercise through modifications of neuroimmune responses, specifically in MDD, SCH, AD and PD.

Prefrontal and Hippocampal Brain Volume Deficits: Role of Low Physical Activity on Brain Plasticity in First-Episode Schizophrenia Patients

Our objective in the present study was to conduct the first empirical study of the effects of regular physical activity habits and their relationship with brain volume and cortical thickness in patients in the early phase of schizophrenia. Relationships between larger brain volumes and higher physical activity levels have been reported in samples of healthy and aging populations, but have never been explored in first-episode schizophrenia patients.

METHOD

We collected MRI structural scans in 14 first-episode schizophrenia patients with either self-reported low or high physical activity levels. We found a reduction in total gray matter volume, prefrontal cortex (PFC), and hippocampal gray matter volumes in the low physical activity group compared to the high activity group. Cortical thickness in the dorsolateral and orbitofrontal PFC were also significantly reduced in the low physical activity group compared to the high activity group. In the combined sample, greater overall physical activity levels showed a non-significant tendency with better performance on tests of verbal memory and social cognition. Together these pilot study findings suggest that greater amounts of physical activity may have a positive influence on brain health and cognition in first-episode schizophrenia patients and support the implementation of physical exercise interventions in this patient population to improve brain plasticity and cognitive functioning.

Brain-derived neurotrophic factor correlates with functional and cognitive impairment in non-disabled older individuals

We used a complete battery of geriatric and psychometric tests to evaluate whether plasma-borne brain-derived neurotrophic factor (BDNF), a master molecule in neuroplasticity, is associated with the severity of functional and cognitive impairment in non-disabled older individuals. There was a significant positive correlation between BDNF plasma concentrations and the Barthel index, a measurement of the ability of individuals to perform the activities of daily living (p=0.03) and the concentration subcategory measured with the mini mental state examination (MMSE) test (p = 0.01). Furthermore, plasma BDNF inversely and significantly correlated with the blood eosinophil count (p = 0.01), the total cholesterol concentration (p = 0.04), and high-density lipoprotein cholesterol (p=0.04). However, BDNF did not correlate with any other socio-demographic or clinical characteristics, other analytical parameters measured in the blood, or any other geriatric assessment scales. Our results suggest that BDNF may play a role in the pathophysiology of functional impairment in the elderly and in some aspects of cognitive function. However, more studies are needed to understand the relationship between circulating BDNF and functional impairment to determine if BDNF represents a candidate biomarker for this type of cognitive impairment.

Physical Exercise Alleviates Health Defects, Symptoms, and Biomarkers in Schizophrenia Spectrum Disorder

Schizophrenia spectrum disorders are characterized by symptom profiles consisting of positive and negative symptoms, cognitive impairment, and a plethora of genetic, epigenetic, and phenotypic biomarkers. Assorted animal models of these disorders and clinical neurodevelopmental indicators have implicated neurodegeneration as an element in the underlying pathophysiology. Physical exercise or activity regimes--whether aerobic, resistance, or endurance--ameliorate regional brain and functional deficits not only in affected individuals but also in animal models of the disorder. Cognitive deficits, often linked to regional deficits, were alleviated by exercise, as were quality-of-life, independent of disorder staging and risk level. Apoptotic processes intricate to the etiopathogenesis of schizophrenia were likewise attenuated by physical exercise. There is also evidence of manifest benefits endowed by physical exercise in preserving telomere length and integrity. Not least, exercise improves overall health and quality-of-life. The notion of scaffolding as the outcome of physical exercise implies the "buttressing" of regional network circuits, neurocognitive domains, anti-inflammatory defenses, maintenance of telomeric integrity, and neuro-reparative and regenerative processes.

The Impact of Aerobic Exercise on Brain-Derived Neurotrophic Factor and Neurocognition in Individuals With Schizophrenia: A Single-Blind, Randomized Clinical Trial

Individuals with schizophrenia display substantial neurocognitive deficits for which available treatments offer only limited benefits. Yet, findings from studies of animals, clinical and nonclinical populations have linked neurocognitive improvements to increases in aerobic fitness (AF) via aerobic exercise training (AE). Such improvements have been attributed to up-regulation of brain-derived neurotrophic factor (BDNF). However, the impact of AE on neurocognition, and the putative role of BDNF, have not been investigated in schizophrenia. Employing a proof-of-concept, single-blind, randomized clinical trial design, 33 individuals with schizophrenia were randomized to receive standard psychiatric treatment (n = 17; "treatment as usual"; TAU) or attend a 12-week AE program (n = 16) utilizing active-play video games (Xbox 360 Kinect) and traditional AE equipment. Participants completed assessments of AF (indexed by VO2 peak ml/kg/min), neurocognition (MATRICS Consensus Cognitive Battery), and serum-BDNF before and after and 12-week period. Twenty-six participants (79%) completed the study. At follow-up, the AE participants improved their AF by 18.0% vs a -0.5% decline in the TAU group (P = .002) and improved their neurocognition by 15.1% vs -2.0% decline in the TAU group (P = .031). Hierarchical multiple regression analyses indicated that enhancement in AF and increases in BDNF predicted 25.4% and 14.6% of the neurocognitive improvement variance, respectively. The results indicate AE is effective in enhancing neurocognitive functioning in people with schizophrenia and provide preliminary support for the impact of AE-related BDNF up-regulation on neurocognition in this population. Poor AF represents a modifiable risk factor for neurocognitive dysfunction in schizophrenia for which AE training offer a safe, nonstigmatizing, and side-effect-free intervention.