Effects of aerobic exercise on cognitive function in adults with major depressive disorder: A systematic review and meta-analysis.

Background: Major Depressive Disorder (MDD) is a highly prevalent psychiatric disorder that impairs the cognitive function of individuals. Aerobic exercise stands out as a promising non-pharmacological intervention for enhancing cognitive function and promoting brain health.While positive impacts of aerobic exercise on executive function in adults with depression have been documented, a comprehensive understanding of its benefits on overall cognitive function, including memory, attention, and processing speed, along with key moderating factors in adults with MDD, remains unexplored. The purpose of the systematic review and meta-analysis was to investigate the effects of aerobic exercise on overall cognitive function in adults with MDD, and to explore whether cognitive sub-domains, aerobic exercise characteristics, and study and sample variables modify the effects of aerobic exercise on cognition. Methods: Six English electronic databases (Embase, Cochrane Central, Scopus, APA PsycInfo, PubMed, Web of Science) were searched from inception to 2 April 2023. Randomized trials, including adults aged 18 years or above with a diagnosis of clinical depression, of the effects of aerobic exercise on cognitive function in adults with MDD compared to non-aerobic exercise groups were included. A three-level meta-analysis was conducted utilizing a random-effects model in R. The quality of the studies was evaluated using the Physiotherapy Evidence Database (PEDro) scale. The PROSPERO registration number is CRD42022367350. Results: Twelve randomized trials including 945 adults with MDD were included. Results indicated that aerobic exercise significantly improved overall cognitive function (g = 0.21; 95 % confidence intervals [CI] = 0.07, 0.34), and the sub-domains of memory (g = 0.25; 95 % CI = 0.06, 0.44) and executive function (g = 0.12; 95 % CI = 0.04, 0.20). Significant benefits in cognitive function were found from moderate-to-vigorous (mixed) intensity (g = 0.19; 95 % CI = 0.02, 0.37), aerobic exercise conducted 3 times per week (g = 0.23; 95 % CI = 0.10, 0.38), in sessions < 45 min (g = 0.59; 95 % CI = 0.28, 0.90), and 45-60 min (g = 0.16; 95 % CI = 0.07, 0.26), in aerobic exercise intervention ≤ 12 weeks (g = 0. 26; 95 % CI = 0.08, 0.44). Limitations: This review only included peer-reviewed English-language studies, which may lead to a language bias. The results of the Egger's test suggested a potential publication bias. Conclusions: Aerobic exercise is efficacious in improving overall cognitive function and the sub-domains of memory and executive function in adults with major depressive disorder.

Acute Exercise Effect on Neurocognitive Function Among Cognitively Normal Late-Middle-Aged Adults With/Without Genetic Risk of AD: The Moderating Role of Exercise Volume and APOE Genotype.

BACKGROUND: Acute exercise is a behavior that benefits cognitive function; however, its effect on populations with different risks for Alzheimer's disease (AD) and the role of exercise variance and Apolipoprotein E (APOE) genotype on this effect remains unknown. This study explores the acute exercise effect on behavioral and neurocognitive function, and its potential moderation by exercise intensity and duration and APOE genetic risk. METHODS: Fifty-one cognitively normal adults (~36% APOE ε4 carriers) performed the Stroop task under a rest condition and 3 exercise conditions while electroencephalographic activity was assessed. RESULTS: Acute exercise improved cognitive performance assessed through both behavioral and neuroelectrical indices. These benefits were observed regardless of adjustments of intensity and duration at a predetermined exercise volume as well as being evident irrespective of APOE ɛ4 carrier status. CONCLUSIONS: Acute exercise could be proposed as a lifestyle intervention to benefit neurocognitive function in populations with and without genetic risk of AD. Future exploration should further the precise exercise prescription and also the mechanisms underlying the beneficial effects of acute exercise for neurocognitive function. CLINICAL TRIALS REGISTRATION NUMBER: NCT05591313.

Effect of acute concurrent exercise training and the mediating role of lactate on executive function: An ERP study.

Both acute aerobic (AE) and resistance exercise (RE) have been acknowledged to be effective methods in enhancing executive function and brain-related P3 amplitudes. Nevertheless, the effect of acute concurrent exercise training (CET), combining both AE and RE, on executive function remains subject to speculation. Moreover, investigation of the mechanisms that underlie improvements in executive function would facilitate scientific understanding. Notably, lactate has emerged as a candidate among several potential mechanisms. Therefore, the main aim of the present study was to investigate the effect of acute CET on the cognitive flexibility dimension of executive function using behavioural and neuro-electric measures. A secondary aim was to determine the mediating effect of blood lactate in the acute exercise-executive function relationship. Seventy-eight young adults (38 women, 40 men; 22.8 ± 1.8 years) were randomly assigned to one of the following groups: CET, AE, or reading control (RC). Cognitive flexibility was evaluated using the Task-Switching Test and its derived electroencephalography (EEG) was assessed immediately prior to and following each treatment. Fingertip lactate assays were taken prior to, at the midpoint, and after each treatment. Both acute CET and AE shortened response time regardless of test conditions when compared to the RC group. Greater P3 amplitude was observed following CET in the heterogeneous condition and under AE in the switch condition. A significant mediation of blood lactate for response time emerged in both the CET and AE groups for the heterogeneous and switch conditions. The blood lactate mediation was not reflected in P3 amplitude. The present findings suggest that acute CET leads to positive behavioural and neuro-electric alterations of cognitive flexibility, and its effect is similar to AE. Additionally, blood lactate serves as a mediator of the effects of acute exercise on executive function from a behavioural, but not neuro-electric standpoint.

Acute effect of combined exercise with aerobic and resistance exercises on executive function.

Objective: Recent studies indicate that acute exercise, whether aerobic exercise (AE) or resistance exercise (RE), improves cognitive function. However, the effects on cognitive function of combined exercise (CE), involving both AE and RE in an exercise session, remain unknown. The aim of this study was to investigate the effects of acute CE on cognitive function. Design: Within-subject design with counterbalancing. Methods: Fifteen healthy men with a sedentary lifestyle in the previous three months were recruited. The participants were assessed for muscular fitness after performing four upper body exercises for a 10-repetition maximum and underwent a submaximal aerobic fitness assessment for V̇O2peak and corresponding workload (watts). They were then assigned to a CE, RE, or sitting control (SC) session in counterbalanced order and were assessed with the Stroop Color and Word Test (SCWT) after each session. Results: Acute CE led to a significantly shorter response time compared to SC (p < .05) in the SCWT, wherein there were no significant differences between acute CE and RE (p = 1.00). Additionally, no significant differences in the accuracy rate were observed across the different sessions (ps > .05). Conclusion: A single session of moderate-intensity CE improved response time in the SCWT, comparable to RE. CE shows promise for enhancing cognitive function, warranting further research on its benefits and other exercise modalities.

The influence of volume-matched acute aerobic exercise on inhibitory control in late-middle-aged and older adults: A neuroelectric study.

Acute aerobic exercise has been shown to benefit inhibitory control; however, less attention has been devoted to the effects of varying intensity and duration with a predetermined exercise volume. The current study assessed the influence of three distinct exercise conditions, each equated with a predesignated exercise volume but varied in terms of exercise durations and intensities, on inhibitory control utilizing both behavioral and neuroelectric measures obtained among late-middle-aged and older adults. Thirty-four adults (61.76 ± 0.80 years) completed three exercise conditions [i.e., a 30-min low-intensity exercise (LIE), a 20-min moderate-intensity exercise (MIE), and a 16-min high-intensity exercise (HIE)] and a non-exercise reading control condition (CON) on separate days. The exercise volumes of LIE and HIE were designed to match the exercise volume of MIE. Following cessation of each condition, the Stroop task was performed while event-related potentials were recorded. Improved behavioral performance (i.e., shorter response time, higher accuracy, and smaller interference scores) was observed after LIE, MIE, and HIE than CON (ps < .005). Additionally, whereas a larger P3b amplitude was only observed following MIE compared to CON (p < .01), larger N2 and smaller N450 amplitudes were observed following all three exercise conditions compared to CON (ps < .005). These findings suggested that while MIE may provide additional benefits for attentional resource allocation, exercise conditions volume matched to MIE resulted in superior inhibitory control, paralleled by modulations of the neural underpinnings of conflict monitoring/detection.

Effects of exercise types on white matter microstructure in late midlife adults: Preliminary results from a diffusion tensor imaging study.

Higher aerobic fitness during late midlife is associated with higher white matter (WM) microstructure. Compared with individuals engaged in irregular exercise, those who engage in regular aerobic exercise show higher fractional anisotropy (FA), a diffusion tenor imaging (DTI) measure that provides an index of WM microstructural integrity. However, whether other types of exercise, such as Tai Chi, can also facilitate WM changes in adults during late midlife remains unknown. The present study compares two types of exercise, Tai Chi and walking, with a sedentary control group, in order to examine the effects of exercise on WM microstructure and determine the regional specificity of WM differences. Thirty-six healthy adults between the ages of 55 and 65 years participated in the study. Based on the participants' exercise habits, they were allocated into three groups: Tai Chi, walking, or sedentary control. All participants were required to complete physical fitness measurements and completed magnetic reasoning imaging (MRI) scans. Our results revealed that the Tai Chi group exhibited a higher FA value in the left cerebral peduncle, compared to the sedentary control group. We also observed that both the Tai Chi and walking groups exhibited higher FA values in the right uncinate fasciculus and the left external capsule, in comparison to the sedentary control group. Increased FA values in these regions was positively correlated with higher levels of physical fitness measurements (i.e., peak oxygen uptake [VO2peak], muscular endurance/number of push-up, agility, power). These findings collectively suggest that regular exercise is associated with improved WM microstructural integrity, regardless of the exercise type, which could guide the development and application of future prevention and intervention strategies designed to address age-related cognitive impairments during late midlife.

Effects of Acute Resistance Exercise on Executive Function: A Systematic Review of the Moderating Role of Intensity and Executive Function Domain.

BACKGROUND: Research has demonstrated that there is a beneficial effect of acute exercise on cognitive function; however, the moderators of the acute resistance exercise (RE) effect on executive function (EF) are underestimated. This systematic review aims to clarify the effects of acute RE on EF by examining the moderating effect of exercise intensity (light, moderate, and vigorous) and EF domains (inhibitory control, working memory, and cognitive flexibility), as well as their interactions. METHODS: The search strategy was conducted in four databases (PubMed, Scopus, PsycARTICLES, and Cochrane Library) prior to January 29, 2022. Included studies had to: (1) investigate acute RE in adults with normal cognition and without diagnosed disease; (2) include a control group or control session for comparison; (3) include outcomes related to the core EF domains; and (4) be published in English. The methodological quality of the included studies was judged according to the PEDro scale guidelines. RESULTS: Nineteen studies were included which included a total of 692 participants. More than half of the outcomes (24/42, 57.14%) indicate that acute RE had a statistically significant positive effect on overall EF. In terms of RE intensity and EF domain, moderate intensity acute RE benefited EF more consistently than light and vigorous intensity acute RE. Acute RE-induced EF benefits were more often found for inhibitory control than for working memory and cognitive flexibility. When considering moderators simultaneously, measuring inhibitory control after light or moderate intensity RE and measuring working memory or cognitive flexibility after moderate intensity RE most often resulted in statistically significant positive outcomes. CONCLUSION: Acute RE has a beneficial effect on EF, observed most consistently for inhibitory control following moderate intensity RE. Future studies should include all exercise intensities and EF domains as well as investigate other potential moderators to enable a better understanding of the benefits of acute RE on EF.

The multi-domain exercise intervention for memory and brain function in late middle-aged and older adults at risk for Alzheimer's disease: A protocol for Western-Eastern Brain Fitness Integration Training trial.

Background: Aging is associated with cognitive decline, increased risk for dementia, and deterioration of brain function. Modifiable lifestyle factors (e.g., exercise, meditation, and social interaction) have been proposed to benefit memory and brain function. However, previous studies have focused on a single exercise modality or a single lifestyle factor. Consequently, the effect of a more comprehensive exercise program that combines multiple exercise modalities and lifestyle factors, as well as examines potential mediators and moderators, on cognitive function and brain health in late middle-aged and older adults remains understudied. This study's primary aim is to examine the effect of a multi-domain exercise intervention on memory and brain function in cognitively healthy late middle-aged and older adults. In addition, we will examine whether apolipoprotein E (ApoE) genotypes, physical fitness (i.e., cardiovascular fitness, body composition, muscular fitness, flexibility, balance, and power), and brain-derived neurotrophic factor (BDNF) moderate and mediate the exercise intervention effects on memory and brain function. Methods: The Western-Eastern Brain Fitness Integration Training (WE-BFit) is a single-blinded, double-arm, 6-month randomized controlled trial. One hundred cognitively healthy adults, aged 45-70 years, with different risks for Alzheimer's disease (i.e., ApoE genotype) will be recruited and randomized into either a multi-domain exercise group or an online educational course control group. The exercise intervention consists of one 90-min on-site and several online sessions up to 60 min per week for 6 months. Working memory, episodic memory, physical fitness, and BDNF will be assessed before and after the 6-month intervention. The effects of the WE-BFit on memory and brain function will be described and analyzed. We will further examine how ApoE genotype and changes in physical fitness and BDNF affect the effects of the intervention. Discussion: WE-BFit is designed to improve memory and brain function using a multi-domain exercise intervention. The results will provide insight into the implementation of an exercise intervention with multiple domains to preserve memory and brain function in adults with genetic risk levels for Alzheimer's disease. Clinical trial registration: ClinicalTrials.gov, identifier: NCT05068271.

The Association of Obesity and Cardiorespiratory Fitness in Relation to Cognitive Flexibility: An Event-Related Potential Study.

This study investigates an association between obesity and cardiorespiratory fitness concerning their potential effects on cognitive flexibility in young adults from behavioral and neuroelectrical perspectives. Eligible young adults (N = 140, 18-25 years) were assigned into one of four groups, according to their status of obesity (i.e., body mass index) and cardiorespiratory fitness levels (i.e., estimated maximal oxygen uptake), namely, normal weight with high cardiorespiratory fitness (NH), obese with high cardiorespiratory fitness (OH), normal weight with low cardiorespiratory fitness (NL), and obese with low cardiorespiratory fitness (OL). The task-switching test was utilized, and its induced endogenous (P3) and exogenous (N1) event-related potential components were recorded. Concerning behavioral indices, the NH demonstrated superior behavioral performance across global switching and local switching of the task-switching test compared to individuals with lower cardiorespiratory fitness and obesity (i.e., NL, OH, and OL). Additionally, the OH demonstrated better performance than the OL during the heterogeneous condition. For neuroelectrical indices, the NH had larger mean P3 amplitudes during global and local switching than the other three groups. A larger N1 amplitude was also observed in the NH during local switching than in the OH group. The findings suggest that cardiorespiratory fitness has beneficial effects on cognitive flexibility, attentional resource allocation, and sensory evaluation in young adults. Furthermore, our research provided novel evidence showing that cardiorespiratory fitness might potentially alleviate the adverse effects of obesity on cognitive flexibility in young adults.

Cardiorespiratory fitness is associated with sustained neurocognitive function during a prolonged inhibitory control task in young adults: An ERP study.

Although beneficial associations between cardiorespiratory fitness and cognitive function have been established, whether cardiorespiratory fitness is related to behavioral and neuroelectric indices of performance during a prolonged inhibitory control task remains unknown. Young adults, categorized into High and Low Fitness groups, completed a 60-min Stroop task, while the N1 and P3 components of event-related potentials were measured. The results showed that the High Fitness group demonstrated shorter response times, regardless of the Stroop task congruency or time-on-task, than Low Fitness group. The High Fitness group also exhibited larger P3 amplitudes than the Low Fitness group, but no differences in N1 amplitudes were observed. These findings suggest that cardiorespiratory fitness during young adulthood has beneficial effects on task performance and attention allocation during an inhibitory control task, and these benefits can be sustained for 60 min.