Resistance training in patients with schizophrenia: Concept and proof of principle trial

As We Were and as We Should Be, Combined Exercise Training in Adults with Schizophrenia: CORTEX-SP Study Part I

INTRODUCTION

Given the health benefits and the role of exercise as an anti-inflammatory adjuvant program, this study aimed to determine the effectiveness of a combined exercise program on cardiorespiratory fitness (CRF), body composition, and biochemical levels in adults with schizophrenia (SZ) characterized at baseline as metabolically unhealthy overweight with low CRF.

METHODS

Participants diagnosed with SZ ( n = 112, 41.3 ± 10.4 yr, 28.7% women) were randomly assigned into a treatment-as-usual control group ( n = 53) or a supervised exercise group ( n = 59, 3 d·wk -1 ). Each combined exercise session consisted of both a low-volume high-intensity interval training (<10 min of high-intensity time per session) and a resistance circuit-training program. All variables were assessed before and after the intervention (20 wk). For the assessment of CRF, a peak cardiopulmonary exercise test on a cycle ergometer was used.

RESULTS

After the intervention, participants from the exercise group ( n = 51) showed increases in CRF ( P < 0.001) through peak oxygen uptake (L·min -1 ; Δ = 17.6%; mL·kg -1 ·min -1 , Δ = 19.6%) and the metabolic equivalent of task (Δ = 19%), with no significant changes ( P > 0.05) in body composition and biochemical variables. However, the treatment-as-usual group ( n = 38) did not show any significant change in the study variables ( P > 0.05). Between-group significant differences ( P ≤ 0.05) were observed in CRF, first ventilatory threshold, and heart rate peak after the intervention period, favoring the exercise group.

CONCLUSIONS

This study demonstrated that a supervised combined exercise program in people with SZ helps to maintain body composition values and improve CRF levels. This could lead to an important clinical change in the characterization from metabolically unhealthy overweight to a metabolically healthy overweight population. Hence, exercise should be considered a co-adjuvant program in the treatment of the SZ population.

The Impact of Regular Physical Exercise on Psychopathology, Cognition, and Quality of Life in Patients Diagnosed with Schizophrenia: A Scoping Review

The presence of less healthy lifestyle habits among individuals diagnosed with schizophrenia which can contribute to the escalation of physical disorders and exacerbation of psychological symptoms is well documented. The present scoping review aims to synthesize and evaluate the available evidence regarding the impact of regular physical exercise on psychopathology, cognition, and quality of life (QoL) in patients diagnosed with schizophrenia. A literature search was performed across Web of Science, SCOPUS, PubMed, and SPORTDiscus for randomized control trials published up to April 2022. Two independent reviewers applied the selection criteria and a third reviewer resolved discrepancies. A total of twelve studies were included, of which nine used endurance training and three used concurrent training (one of these additionally used resistance training). The results reveal benefits of various modalities of supervised regular exercise in the psychopathology of schizophrenia. Furthermore, regular endurance training seems to improve cognitive function in patients with schizophrenia and promote their QoL; however, results are inconclusive with respect to this last variable. The assessment of methodological quality in the reviewed articles indicates a high overall risk of bias, particularly in relation to deviations from intended interventions and the selection of reported results. Furthermore, an assessment of exercise reporting revealed that only 5 out of 19 items were fulfilled in more than 50% of the articles. Future research is needed to evaluate the effects of different training modalities and the optimal dose-response relationship in patients diagnosed with schizophrenia.

The effect of exercise on global, social, daily living and occupational functioning in people living with schizophrenia: A systematic review and meta-analysis

BACKGROUND

Schizophrenia is associated with high rates of global, social and occupational functional impairments. While prior meta-analyses have extensively examined the impact of exercise on physical and mental health, the impact on functioning in schizophrenia have yet to be fully established. This review aimed to update the evidence base regarding the impact of exercise on functioning in schizophrenia, and explore moderators of effect.

METHODS

A systematic search was conducted to identify randomized controlled trials (RCTs) of exercise evaluating global functioning versus any comparator in people with schizophrenia; between group meta-analyses of global functioning (and secondary - social, living skills, occupational, adverse events) were computed using a random effects model. Subgroup analyses based on diagnosis and aspects of the intervention were conducted.

RESULTS

18 full text articles were included, involving 734 participants. A moderate impact of exercise on global functioning was found (g = 0.40, 95 % C·I. = 0.12 to 0.69, p = 0.006), with a moderate impact of exercise on social (N = 5, g = 0.54 95 % C.I = 0.16 to 0.9 p = 0.005), and daily living functioning (N = 3, g = 0.65, 95 % C.I. = 0.07 to 1.22, p = 0.005).

CONCLUSIONS

There is good evidence that exercise can improve the global functioning of people with schizophrenia, with preliminary evidence for social and daily living skills; exercise should be considered an important adjunct to usual care. Higher impacts on global functioning were seen in aerobic interventions and of at least moderate to vigorous intensity. More research is required into resistance training, in early psychosis cohorts and to evaluate the comparison of exercise with other established psychosocial therapies.

Effects of exercise intervention on psychotic symptoms: A meta-analysis and hypothetical model of neurobiological mechanisms

There is conflicting evidence on the efficacy of exercise as intervention for psychosis. This article aims to analyze the effect of exercise on psychotic symptoms. A database search was conducted in PubMed, Web of Science, Scopus, ScienceDirect, EBSCO and Cochrane CENTRAL, based on a protocol (PROSPERO: CRD42022326944). Papers available by March 2023 assessing exercise interventions in psychotic patients were included. A significant improvement was found in Positive and Negative Syndrome Scale (PANSS) positive symptoms (MD = -0.75 [-1.35, -0.15], p = 0.01), with large effect sizes for PANSS-negative and general symptoms (-2.14 [-3.36, -0.92]) and (-2.53 [-3.15, -1.91]), respectively. Heterogeneity was high among studies, 49 and 73% for PANSS-positive and negative symptoms, and low, 0%, for general symptoms. It was hypothesized that functioning of specific brain areas, such as the temporal lobe and hippocampus, may underlie the improvement seen with exercise. Based on neuroimaging/neurophysiology studies, we propose a neurobiological model accounting for the association between exercise and psychotic symptom improvement.

Effects of Aerobic, Resistance, and Combined Exercise Training on Psychiatric Symptom Severity and Related Health Measures in Adults Living With Schizophrenia: A Systematic Review and Meta-Analysis

Previous research has demonstrated the efficacy, effectiveness, and safety of exercise training in persons living with schizophrenia. However, the optimal exercise training program remains unclear. The aim of this paper was to conduct a systematic review and meta-analysis of the effects of aerobic, resistance, and combined aerobic and resistance training on health-related physical fitness and positive and negative symptoms in persons living with schizophrenia. Six electronic databases were searched systematically from their inception to December 2020 [MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, SPORTDiscus, and Cumulative Index to Nursing and Allied Health Literature (CINAHL)] to identify literature examining the effects of exercise training on psychiatric symptoms and health-related physical fitness indicators in persons living with schizophrenia. A total of 22 studies (n = 913) were included in this review, and 12 studies (n = 554) included within the meta-analysis reported the effects of exercise training (aerobic, resistance, and combined aerobic and resistance) in persons living with schizophrenia. Aerobic training had a significant decrease on Positive and Negative Syndrome Scale (PANSS) negative scores (ES −2.28, 95% CI −3.57 to −1.00; p = 0.0005) and PANSS general scores (ES −2.51, 95% CI −3.47 to −1.55; p &lt; 0.00001). Resistance training did not lead to significant effects on PANSS total scores. Combined aerobic and resistance training did not lead to significant changes in body mass index, PANSS positive scores, or PANSS total scores. However, grouping together the results from all exercise training modalities (including aerobic training, resistance training, and combined aerobic and resistance training) revealed significant effects on body mass index (ES 1.86, 95% CI 0.84 to 2.88; p = 0.0003), maximal/peak oxygen consumption (ES 2.54, 95% CI 1.47 to 3.62; p = &lt; 0.00001), body weight (ES 6.58, 95% CI 2.94 to 10.22; p = 0.0004), PANSS negative scores (ES −1.90, 95% CI −2.70 to −1.10; p &lt; 0.00001), and Scale for the Assessment of Negative Symptoms (SANS) total (ES −14.90, 95% CI −22.07 to −7.74; p &lt; 0.0001). Collectively, these findings support the importance of exercise participation (aerobic and resistance training) in persons living with schizophrenia.

Aerobic exercise in severe mental illness: requirements from the perspective of sports medicine

Major depression, bipolar disorder, and schizophrenia are severe mental illnesses. Despite receiving psychopharmacological and psychosocial treatments, about half of patients develop a chronic course with residual cognitive and negative symptoms and have a high risk for cardiovascular disease and reduced life expectancy. Therefore, add-on innovative treatment approaches are needed to improve outcome. Aerobic exercise interventions have been shown to improve global functioning, cognition, and negative and depressive symptoms in these patients. The basic mechanism of these exercise-related changes has been reported to be improved brain plasticity, e.g., increased volume of disease-related brain regions such as the hippocampus. The optimal type, duration, and frequency of exercise have not yet been determined and need to be addressed in supervised physical exercise studies. Because of the low physical activity levels, lack of drive related to negative and depressive symptoms, and high prevalence of cardiovascular comorbidities in patients with severe mental illness, besides aiming to improve symptoms of mental illness, exercise interventions should also aim to increase cardiorespiratory fitness, which they should comprehensively assess by direct measurements of maximal oxygen uptake. Based on the recommendations for developing cardiorespiratory fitness by the American College of Sports Medicine, 150 min moderate-intensity training per week or vigorous-intensity exercise training for 75 min per week are appropriate. Most studies have had relatively short intervention periods, so future studies should focus on long-term adherence to exercise by implementing motivational strategies supported by telemedicine and by identifying and targeting typical barriers to exercise in this patient population.