The Magic of Movement; the Potential of Exercise to Improve Cognition

The neuromuscular basis of functional impairment in schizophrenia: A scoping review

Patients with schizophrenia exhibit functional impairments in their locomotory tasks, which decreases their quality of life. Due to the limited current research, the neuromuscular mechanisms behind the functional impairments in patients is not fully understood. Thus, this review aims to summarize the neuromuscular mechanisms that underlie these deficits in daily functioning. These deficits are speculated to stem from abnormalities at various levels from neurons through to the skeletal muscles. The neurological abnormalities are exhibited as lower motor neuron dysfunction whereas the skeletal muscle pathology is shown as increased muscle fibre (type 1 and type 2) atrophy, reduction in maximal force generation, and increased strength loss per decade. Although antipsychotics effectively reduce positive symptoms, functional impairments remain unresolved. Both endurance and resistance training have shown potential benefits in alleviating deficits in daily functioning by increasing muscular strength, increasing fat-free mass, and preserving neuromuscular properties from degradation. In summary, the review elucidates various possible mechanisms for the onset of functional impairment experienced by patients with schizophrenia and highlights the potential utility of endurance and resistance training to alleviate these deficits in daily functioning.

Aerobic exercise and cognitive functioning in schizophrenia: An updated systematic review and meta-analysis

This study serves as an update to a recent systematic review and meta-analysis to summarize the effect of aerobic exercise on cognition in schizophrenia and determine the most effective method of aerobic exercise. We searched for controlled studies investigating the effect of aerobic exercise on cognition in schizophrenia published until January 2021. Fifteen studies were included. A random-effects model was used to estimate the standardized mean differences (SMDs) between cognitive outcomes of aerobic exercises and controls. Compared with controls, aerobic exercises resulted in significant improvements in global cognition (SMD = 0.21), attention/vigilance (SMD = 0.32), working memory (SMD = 0.27), and verbal learning (SMD = 0.30). Significant improvements in global cognition were observed with group exercise (SMD = 0.28), exercise supervised by exercise professionals (SMD = 0.27), as well as with ≥ 90 min/week (SMD = 0.26) and ≥ 12 weeks duration (SMD = 0.22). Our findings provide information beneficial for determining the most effective aerobic exercise method to improve cognition in schizophrenia.

Effects of aerobic walking on cognitive function in patients with schizophrenia: A randomized controlled trial

Cognitive deficits, which are core manifestations in schizophrenia and exhibit a limited response to antipsychotic treatment, contribute to poor treatment outcomes and functional disability. Evidence on the effect of aerobic walking (AW) and exercise intensity on cognitive function in patients with schizophrenia is lacking. In total, 79 patients with schizophrenia were recruited for a 12-week randomized control trial and allocated to the treatment-as-usual (TAU, n = 38) and treatment-as-usual plus AW (TAW, n = 39) groups. The TAW participants joined a supervised 12-week AW program consisting of 30-min sessions five times per week while wearing a Fitbit Charge 2 device. Cognitive function was evaluated using the Brief Assessment of Cognition in Schizophrenia. After randomization, 67 (34 TAU and 33 TAW) participants joined the 12-week trial and were included in the intention-to-treat analysis. Multivariate general linear model repeated measures analysis revealed no significant time × group interaction effect on cognitive function changes between the TAU and TAW groups and a marginally significant group effect on verbal fluency (p = 0.09). The interaction effect of time and treatment group on verbal fluency (p = 0.05) was marginally significant between the high and low AW intensity groups, whereas a significant group effect on attention and processing speed (p = 0.04) was observed. Supervised 12-week AW of moderate intensity may have potential cognitive benefits for patients with schizophrenia.

What prevents youth at clinical high risk for psychosis from engaging in physical activity? An examination of the barriers to physical activity

BACKGROUND

Exercise has increasingly been proposed as a healthful intervention prior to and after the onset of psychosis. There is some evidence to suggest that youth at clinical high risk (CHR) for psychosis are less physically active and report more barriers to engaging in exercise; however, there has been relatively limited empirical work documenting this phenomenon, and to date, relationships between physical activity, barriers, and clinical phenomenology have been unclear.

METHODS

CHR (N = 51) and healthy control (N = 37) participants completed a structured clinical interview assessing attenuated psychotic symptoms and substance use, and an exercise survey that assessed current exercise practices, perceived physical fitness, and barriers related to engaging in exercise.

RESULTS

CHR youth engaged in less physical activity, exhibited lower perception of fitness, and endorsed more barriers related to motivation for exercise. The CHR group showed significant negative correlations where lower perceptions of fitness were associated with increased negative, disorganized, and general symptoms. Decreased frequency of activity was related to more barriers of motivation. Interestingly, greater symptomatology in the CHR group was associated with more barriers of self-perception and motivation for engaging in exercise. However, findings suggested a nuanced relationship in this area; for example, increased physical activity was associated with increased substance use.

CONCLUSIONS

The results of the current study support the notion that sedentary behavior is common in CHR youth, and more broadly, provide an impetus to target motivation through supervised exercise and fitness tracking to promote the health and well-being of CHR individuals.

Aerobic Exercise Improves Cognitive Functioning in People With Schizophrenia: A Systematic Review and Meta-Analysis

Cognitive deficits are pervasive among people with schizophrenia and treatment options are limited. There has been an increased interest in the neurocognitive benefits of exercise, but a comprehensive evaluation of studies to date is lacking. We therefore conducted a meta-analysis of all controlled trials investigating the cognitive outcomes of exercise interventions in schizophrenia. Studies were identified from a systematic search across major electronic databases from inception to April 2016. Meta-analyses were used to calculate pooled effect sizes (Hedges g) and 95% CIs. We identified 10 eligible trials with cognitive outcome data for 385 patients with schizophrenia. Exercise significantly improved global cognition (g = 0.33, 95% CI = 0.13-0.53, P = .001) with no statistical heterogeneity (I2 = 0%). The effect size in the 7 studies which were randomized controlled trials was g = 0.43 (P < .001). Meta-regression analyses indicated that greater amounts of exercise are associated with larger improvements in global cognition (β = .005, P = .065). Interventions which were supervised by physical activity professionals were also more effective (g = 0.47, P < .001). Exercise significantly improved the cognitive domains of working memory (g = 0.39, P = .024, N = 7, n = 282), social cognition (g = 0.71, P = .002, N = 3, n = 81), and attention/vigilance (g = 0.66, P = .005, N = 3, n = 104). Effects on processing speed, verbal memory, visual memory and reasoning and problem solving were not significant. This meta-analysis provides evidence that exercise can improve cognitive functioning among people with schizophrenia, particularly from interventions using higher dosages of exercise. Given the challenges in improving cognition, and the wider health benefits of exercise, a greater focus on providing supervised exercise to people with schizophrenia is needed.

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.