Resistance exercise and episodic memory function: a systematic review

Delirium management in perioperative geriatric services: a narrative review of non-pharmaceutical strategies

Delirium, a common complication in elderly surgical patients, poses significant challenges in perioperative care. Perioperative geriatric services (PGS) aim at managing comorbidities, postoperative complications, and initiating early recovery of mobility to enhance elderly patients' prognosis in the perioperative period. Studies have shown that patients with preoperative cognitive disorders are at a significantly increased risk of postoperative delirium. While postoperative delirium affects up to 70% of people over 60 and 90% of people with neurodegenerative diseases, it remains underdiagnosed in many cases. Postoperative delirium can lead to functional decline, prolonged hospitalization, increased healthcare costs, cognitive impairment, and psychological malaise. This article briefly summarizes the literature on delirium, its risk factors, and its non-pharmaceutical management strategies within the perioperative period. It highlights the importance of integrating cognitive and psychological assessments into perioperative care protocols to provide baseline data, improve patient outcomes, reduce hospital stays, and minimize complications associated with delirium. By embracing evidence-based delirium management protocols, healthcare professionals can better identify and manage delirium, ultimately improving the quality of care for elderly surgical patients, which would also benefit healthcare staff and healthcare institutions.

Neuroprotection in metabolic syndrome by environmental enrichment. A lifespan perspective

Metabolic syndrome (MetS) is defined by the concurrence of different metabolic conditions: obesity, hypertension, dyslipidemia, and hyperglycemia. Its incidence has been increasingly rising over the past decades and has become a global health problem. MetS has deleterious consequences on the central nervous system (CNS) and neurological development. MetS can last several years or be lifelong, affecting the CNS in different ways and treatments can help manage condition, though there is no known cure. The early childhood years are extremely important in neurodevelopment, which extends beyond, encompassing a lifetime. Neuroplastic changes take place all life through - childhood, adolescence, adulthood, and old age - are highly sensitive to environmental input. Environmental factors have an important role in the etiopathogenesis and treatment of MetS, so environmental enrichment (EE) stands as a promising non-invasive therapeutic approach. While the EE paradigm has been designed for animal housing, its principles can be and actually are applied in cognitive, sensory, social, and physical stimulation programs for humans. Here, we briefly review the central milestones in neurodevelopment at each life stage, along with the research studies carried out on how MetS affects neurodevelopment at each life stage and the contributions that EE models can provide to improve health over the lifespan.

Memory impairment and its associated risk and protective factors among older adults in Indonesia

AIMS

This study aimed to evaluate the association between memory impairment and its risk and protective factors, focusing on demographic and health-related variables among older adults in Indonesia.

METHOD

The data analyzed were the Indonesian Family Life Survey-5 (IFLS-5) using cross-sectional variables of 4236 older adults aged 60 years and over included in the 2015 round. Memory impairment was assessed by immediate word list recall from the Telephone Interview for Cognitive Status (TICS). Sociodemographic factors and multiple health variables were included as predictors. Data were analyzed using frequency analyses bivariate and stepwise logistic regression tests.

RESULT

Among 4236 older adults, 49.7% were male and 50.3% were female. Stepwise backward analyses showed that memory impairment was independently associated with older age, being female, or not in a union (unmarried, separated, divorced, or widowed), having obtained low levels of education, living in a rural area, reporting low life satisfaction, low social capital, higher dependency, and having clinical depression. Only moderate (but not high or low) physical activity levels were associated with a lower risk. Being underweight increased the risk, but being overweight/obese (as assessed by BMI) protective factors for a lower immediate recall score.

CONCLUSION

Increasing education and continued engagement of older adults in psychosocial activities, including moderate physical activity, improving mental health, preventing weight loss, and maintaining functional ability to decrease dependency, are associated with increased episodic memory, especially in non-married and older women in rural areas of Indonesia.

Effects of Classroom-Based Resistance Training With and Without Cognitive Training on Adolescents' Cognitive Function, On-task Behavior, and Muscular Fitness

Aim: Participation in classroom physical activity breaks may improve children's cognition, but few studies have involved adolescents. The primary aim of this study was to examine the effects of classroom-based resistance training with and without cognitive training on adolescents' cognitive function. Methods: Participants were 97 secondary school students (45.4% females, mean age 15.78 ± 0.44). Four-year 10 classes from one school were included in this four-arm cluster randomized controlled trial. Classes were randomly assigned to the following groups: sedentary control with no cognitive training, sedentary with cognitive training, resistance training without cognitive training, and resistance training with cognitive training. Sessions varied in levels of both cognitive demand and resistance training (i.e., high vs. low) and were administered three times per week for 4 weeks (12 sessions). Inhibition, cognitive flexibility, episodic memory, on-task behavior, and muscular fitness were assessed at baseline and post-test. Linear mixed models were used to examine changes within and between groups. Results: In comparison with the control group, episodic memory improved significantly in the resistance training without cognitive training group (-9.87 units, 95% CI: -17.71 to -2.03, p = 0.014, d = 0.72). There were no group-by-time effects for inhibition or cognitive flexibility. Classroom activity breaks both with and without cognitive demand improved participants' on-task behavior in comparison with the control and sedentary group. The resistance training programs did not lead to improvements in muscular fitness. Conclusion: Participation in body weight resistance training without cognitive training led to selective improvements in episodic memory. No training effects were found for inhibition or cognitive flexibility. A longer study period may be necessary to induce improvements in muscular fitness and associated changes in inhibition and cognitive flexibility. Clinical Trial Registration: https://www.anzctr.org.au/ACTRN12621001341819.aspx, Australian New Zealand Clinical Trials Registry-ACTRN12621001341819.

Cathepsin B and Muscular Strength are Independently Associated with Cognitive Control

Although muscular strength has been linked to greater cognitive function across different cognitive domains, the mechanism(s) through which this occurs remain(s) poorly understood. Indeed, while an emerging body of literature suggests peripheral myokines released from muscular contractions may play a role in this relationship, additional research is needed to understand this link. Accordingly, this study sought to compare the influences of a particular myokine, Cathepsin B (CTSB), and muscular strength on hippocampal-dependent relational memory and cognitive control in 40 adults (age = 50.0±7.3 yrs). Overnight fasted venous blood draws were taken to assess plasma CTSB and muscular strength was assessed as maximal isokinetic strength testing using a Biodex dynamometer. Cognitive performance was assessed using a Spatial Reconstruction Task to assess relational memory and a modified Flanker task to assess cognitive control. Neuroelectric function for cognitive control was assessed using event-related potentials (ERPs) recorded during the Flanker task. Initial bivariate correlational analyses revealed that neither sex, age, lean body mass, or muscular strength was associated with CTSB. However, CTSB was inversely associated with reaction time and fractional peak latency of the P3 component of the Flanker task. Muscular strength was also inversely associated with reaction time and positively associated with relational memory performance. However, the influence of muscular strength on relational memory did not persist following adjustment for covariates. Greater circulating CTSB was selectively associated with greater cognitive control as well as faster information processing speed. These findings are the first to link circulating CTSB to both cognitive control and neuroelectric function. Future intervention studies are needed to examine the effects of changes in muscular strength, circulating myokines, and different domains of cognitive function.

Can acute resistance exercise facilitate episodic memory encoding?

Research has shown benefits of physical exercise on memory performance when carried out before or after a memory task. The effects of concurrent physical exercise and particularly resistance exercise are still inconclusive. The current study investigates the influence of resistance exercise with two intensities (fast and slow squats) on performance in a wordlist learning task using a within-subject design. Sport students (N = 58, Mage = 23 years; 26 women) were trained in a mnemonic technique to encode word lists (method of loci). In each session they were asked to encode two lists, each consisting of 20 words. During encoding, participants either performed one squat per word (fast-squat-condition), one squat every second word (slow-squat-condition), or stayed seated (control-condition). Participants performed three sessions for each condition, in counterbalanced order. Heart rates differed significantly according to exercise intensity. Memory performances in the sitting condition were better, compared to the exercise conditions. Performance in sitting and the fast squat conditions improved similarly over time, while performance in the slow squat condition increased faster, and reached the level of the fast squat condition at the end of the study phase. We conclude that light to moderate resistance exercise while working on an episodic memory task may rather represent a dual-task situation (= two tasks that compete for attentional resources). Especially doing a squat every second word may represent an inhibition task that people have to get used to. Future studies should include biochemical markers of arousal and neuronal plasticity in addition to heart rate.

Acute Effects of Moderate versus High-Intensity Strength Exercise on Attention and Mood States in Female Physical Education Students

The presumed benefits of exercise/physical activity on the brain are an important public health issue. However, the experimental approach to understanding the effects of physical activity on the brain, and more particularly on cognitive functions, has only been studied recently. In particular, females remain underrepresented in the research, despite having a specific training/exercise adaptation/response. The aim of the present study was to examine the acute effects of high- and moderate-intensity strength exercise (3 sets of 8–10 repetitions and 3 sets of 6 repetitions, respectively, with each session lasting approximately 30 min) on attention and mood states in female physical education students. Forty-six female physical education students (M_age = 20.02 ± 1.05 years, M_{Body Mass Index} = 21.07) volunteered to participate in this study. They were divided into three groups: a moderate-intensity strength exercise group (MISEG: n = 15), a high-intensity strength exercise group (HISEG: n = 16), and a control group (CG: n = 15). Attention and psychological states were assessed using the d2 test, Rating of Perceived Exertion (RPE) and the Brunel Mood Scale (BRUMS) questionnaire, respectively, before and after each session. The data showed that in the MISEG attention increased, in terms of concentration (p = 0.05). RPE values, fatigue and confusion were higher for the HISEG than the CG (p < 0.05) and the MISEG (p < 0.05). Vigour was higher for the MISEG than other groups (p < 0.05). In conclusion, moderate-intensity resistance exercise is an appropriate method to improve attention in female participants. The elevated cognitive performance may be due to the changes in RPE and mood states (fatigue, vigour and confusion subscales).

Examining the Role of Physical Activity on Word Learning in School-Aged Children

Purpose Previous studies show that there is increased brain activity after exercise, leading to improved word recall in adults. The aim of this study was to examine whether different types of exercise (i.e., aerobic vs. anaerobic) may also lead to improved performance during vocabulary learning in children. Method A total of 48 participants (24 in Experiment 1 and 24 in Experiment 2) between the ages of 6 and 12 years completed a word learning task. Training of words took place in a resting and in an exercise condition using a within-subject design. In the resting measure, children were taught names of novel objects and then colored for 3 min before being tested on their ability to recognize the words. In the exercise condition, the same steps were followed, but instead of coloring, children engaged in 3 min of either aerobic exercise (i.e., swimming in Experiment 1) or anaerobic exercise (i.e., a CrossFit-like workout in Experiment 2). Results In Experiment 1, accuracy of word recognition was significantly higher for words that were trained in the aerobic exercise compared to the resting condition. In Experiment 2, there was no significant difference in performance between the anaerobic exercise and resting conditions. Conclusions These findings suggest that previously identified benefits of exercise on language abilities in adults also extend to school-aged children. However, not all types of physical activity lead to this boost in performance, as only aerobic (but not anaerobic) exercise improved children's ability to acquire new word-object relations. Supplemental Material https://doi.org/10.23641/asha.14462187.

Acute exercise and cognition: A review with testable questions for future research into cognitive enhancement with blood flow restriction

Blood flow restriction, in combination with low load/intensity exercise, has consistently been shown to increase both muscle size and strength. In contrast, the effects of blood flow restricted exercise on cognition have not been well studied. Therefore, the purpose of this paper is 1) to review the currently available literature investigating the impact of blood flow restricted exercise on cognition and 2) to provide some hypotheses for how blood flow restriction might provide an additive stimulus for augmenting specific cognitive domains above exercise alone. Given the lack of research in this area, the effects of blood flow restricted exercise on cognition are still unclear. We hypothesize that blood flow restricted exercise could potentially enhance several cognitive domains (such as attention, executive functioning, and memory) through increases in lactate production, catecholamine concentration, and PGC-1α expression. We review work that suggests that blood flow restriction is not only a beneficial strategy to improve musculoskeletal function but could also be a favorable method for enhancing multiple domains of cognition. Nonetheless, it must be emphasized this is a hypothesis that currently has only minimal experimental support, and further investigations in the future are necessary to test the hypothesis.

Does Aerobic and Resistance Exercise Influence Episodic Memory through Unique Mechanisms?

Aerobic and resistance exercise (acute and chronic) independently and collectively induce beneficial responses in the brain that may influence memory function, including an increase in cerebral blood flow, neurogenesis, neuroelectrical alterations, and protein production. However, whether aerobic and resistance exercise improve memory via similar or distinct mechanisms has yet to be fully explained. Here, we review the unique influence of aerobic and resistance exercise on neural modulation, proteins, receptors, and ultimately, episodic memory. Resistance training may optimize neural communication, information processing and memory encoding by affecting the allocation of attentional resources. Moreover, resistance exercise can reduce inflammatory markers associated with neural communication while increasing peripheral and central BDNF (brain-derived neurotrophic factor) production. Aerobic training increases hippocampal levels of BDNF and TrkB (Tropomyosin receptor kinase B), protein kinases and glutamatergic proteins. Likewise, both aerobic and anaerobic exercise can increase CREB (cAMP response element-binding protein) phosphorylation. Thus, we suggest that aerobic and resistance exercise may influence episodic memory via similar and, potentially, distinct mechanisms.

Environmental and Cognitive Enrichment in Childhood as Protective Factors in the Adult and Aging Brain

Some recent studies have highlighted a link between a favorable childhood environment and the strengthening of neuronal resilience against the changes that occur in natural aging neurodegenerative disease. Many works have assessed the factors – both internal and external – that can contribute to delay the phenotype of an ongoing neurodegenerative brain pathology. At the crossroads of genetic, environmental and lifestyle factors, these relationships are unified by the concept of cognitive reserve (CR). This review focuses on the protective effects of maintaining this CR through the cognitive aging process, and emphasizes the most essential time in life for the development and strengthening of this CR. The in-depth study of this research shows that early stimulation with regard to social and sensory interactions, contributes to the proper development of cognitive, affective and psychosocial capacities. Childhood thus appears to be the most active phase in the development of CR, and as such we hypothesize that this constitutes the first essential period of primary prevention of pathological aging and loss of cognitive capacities. If this hypothesis is correct, early stimulation of the environment would therefore be considered as a true primary prevention and a public health issue. The earlier identification of neurodevelopmental disorders, which can affect personal and professional development across the lifespan, could therefore have longer-term impacts and provide better protection against aging.

Acute Effects of Resistance Exercise on Cognitive Function in Healthy Adults: A Systematic Review with Multilevel Meta-Analysis

BACKGROUND

Recent research has revealed a beneficial impact of chronic resistance exercise (RE) on brain function. However, it is unclear as to whether RE is also effective in an acute setting.

OBJECTIVE

To investigate the immediate effects of a single RE session on cognitive performance in healthy adults.

METHODS

A multilevel meta-analysis with random effects meta-regression model was used to pool the standardized mean differences (SMD) between RE and no-exercise (NEX) as well as between RE and aerobic exercise (AE). In addition to global cognitive function, effects on reported sub-domains (inhibitory control, cognitive flexibility, working memory, attention) were examined.

RESULTS

Twelve trials with fair methodological quality (PEDro scale) were identified. Compared to NEX, RE had a positive effect on global cognition (SMD: 0.56, 95% CI 0.22-0.90, p = 0.004), but was not superior to AE (SMD: - 0.10, 95% CI 0.01 to - 0.20, p = 0.06). Regarding cognitive sub-domains, RE, compared to NEX, improved inhibitory control (SMD: 0.73, 95% CI 0.21-1.26, p = 0.01) and cognitive flexibility (SMD: 0.36, 95% CI 0.17-0.55, p  = 0.004). In contrast, working memory (SMD: 0.35, 95% CI - 0.05 to 0.75, p  = 0.07) and attention (SMD: 0.79, 95% CI - 0.42 to 2.00, p = 0.16) remained unaffected. No significant differences in sub-domains were found between RE and AE (p > 0.05).

CONCLUSION

RE appears to be an appropriate method to immediately enhance cognitive function in healthy adults. Further studies clearly elucidating the impact of effect modifiers such as age, training intensity, or training duration are warranted.

Experimental Effects of Acute High-Intensity Resistance Exercise on Episodic Memory Function: Consideration for Post-Exercise Recovery Period

Background

The present experiments evaluated the effects of acute high-intensity resistance exercise on episodic memory.

Methods

Two experiments were conducted. For Experiment 1, participants (N = 40; M_age = 21.0 years) were randomized into one of two groups, including an experimental exercise group and a control group (seated for 20 min). The experimental group engaged in an acute bout of resistance exercises (circuit style exercises) for 15 minutes, followed by a 5-min recovery period. Memory function was subsequently assessed using a multiple trial (immediate and delay), word-list episodic memory task (Rey Auditory Verbal Learning Test, RAVLT), and then followed by a comprehensive, computerized assessment of episodic memory (Treasure Hunt task, THT). The THT involved a spatio-temporal assessment of what, where, and when components of episodic memory. Experiment 2 evaluated if altering the recovery period would influence the potential negative effects of high-intensity resistance exercise on episodic memory function. For Experiment 2, participants (N = 51) were randomized into the same acute resistance exercise protocol but either with a 10-min recovery period, 20-min recovery period, or a control group.

Results

For Experiment 1, for RAVLT, the exercise group performed worse (F_{group × time} = 3.7, p = .001, η ²p = .09). Across nearly all THT outcomes, the exercise group had worse spatio-temporal memory than the control group. These results suggest that high-intensity resistance exercise (with a 5-min recovery) may have a detrimental effect on episodic memory function. For Experiment 2, for RAVLT, the exercise with 10-min recovery group performed better (F_{group × time} = 3.1, p = .04, η ²p = .11). Unlike Experiment 1, exercise did not impair spatio-temporal memory, with the 20-min exercise recovery group having the best "where" component of episodic memory.

Conclusion

Collectively, the results from these two experiments suggest that acute high-intensity resistance exercise may impair episodic memory when a short exercise recovery period (e.g., 5-min) is employed, but with a longer recovery period (10+ min), acute high-intensity resistance exercise may, potentially, enhance episodic memory.

Effects of Exercise on Long-Term Potentiation in Neuropsychiatric Disorders

Various neuropsychiatric conditions, such as depression, Alzheimer's disease, and Parkinson's disease, demonstrate evidence of impaired long-term potentiation, a cellular correlate of episodic memory function. This chapter discusses the mechanistic effects of these neuropsychiatric conditions on long-term potentiation and how exercise may help to attenuate these detrimental effects.

Physical Activity, Cognition, and Brain Outcomes: A Review of the 2018 Physical Activity Guidelines

PURPOSE

Physical activity (PA) is known to improve cognitive and brain function, but debate continues regarding the consistency and magnitude of its effects, populations and cognitive domains most affected, and parameters necessary to achieve the greatest improvements (e.g., dose).

METHODS

In this umbrella review conducted in part for the 2018 Health and Human Services Physical Activity Guidelines for Americans Advisory Committee, we examined whether PA interventions enhance cognitive and brain outcomes across the life span, as well as in populations experiencing cognitive dysfunction (e.g., schizophrenia). Systematic reviews, meta-analyses, and pooled analyses were used. We further examined whether engaging in greater amounts of PA is associated with a reduced risk of developing cognitive impairment and dementia in late adulthood.

RESULTS

Moderate evidence from randomized controlled trials indicates an association between moderate- to vigorous-intensity PA and improvements in cognition, including performance on academic achievement and neuropsychological tests, such as those measuring processing speed, memory, and executive function. Strong evidence demonstrates that acute bouts of moderate- to vigorous-intensity PA have transient benefits for cognition during the postrecovery period after exercise. Strong evidence demonstrates that greater amounts of PA are associated with a reduced risk of developing cognitive impairment, including Alzheimer's disease. The strength of the findings varies across the life span and in individuals with medical conditions influencing cognition.

CONCLUSIONS

There is moderate-to-strong support that PA benefits cognitive functioning during early and late periods of the life span and in certain populations characterized by cognitive deficits.

The effects of different protocols of physical exercise and rest on long-term memory

Whilst there are many studies comparing the different effects of exercise on long-term memory, these typically adopt varying intensities, durations, and behavioural measures. Furthermore, few studies provide direct comparisons between exercise and different types of rest. Therefore, by providing a standardised methodological design, this study will ascertain the most effective intensity and protocol of exercise for the modulation of long-term memory, whilst directly comparing it to different types rest. This was achieved using the same old/new recognition memory test and an 80-90 min retention interval. Three experiments were performed (total N = 59), each with a three-armed crossover design measuring the extent to which physical exercise and wakeful rest can influence long-term memory performance. In Experiment 1, the effects of continuous moderate intensity exercise (65-75% HR_max), passive rest (no cognitive engagement) and active rest (cognitively engaged) were explored. In Experiment 2, continuous moderate intensity exercise was compared to a type of high-intensity interval training (HIIT) and passive rest. Experiment 3 observed the effects of low- (55-65% HR_max), moderate- and high-intensity (75-85% HR_max) continuous exercise. Across the three experiments moderate intensity exercise had the greatest positive impact on memory performance. Although not significant, HIIT was more effective than passive-rest, and passive rest was more effective than active rest. Our findings suggest that it is not necessary to physically overexert oneself in order to achieve observable improvements to long-term memory. By also investigating wakeful rest, we reaffirmed the importance of the cognitive engagement during consolidation for the formation of long-term memories.

The effects of sedentary behavior on memory and markers of memory function: a systematic review

Objective: To evaluate the association of sedentary behavior on memory and markers of memory among humans of all ages.Methods: PubMed, PsychInfo, Sports Discus and Google Scholar databases were searched. Inclusionary criteria included: Published in English; conducted among humans (children to older adults); employ a cross-sectional, prospective or experimental design; include a measure of sedentary behavior as the independent variable (e.g. time spent sitting or watching television); and include a memory-related outcome measure (e.g. behavioral performance on a memory task, brain tissue volume in a memory structure). Information on participant characteristics, study design, sedentary behavior measure, memory outcome measure, and hypothesized mechanisms were extracted. The relationship between sedentary behavior and memory was synthesized while considering the data extraction parameters.Results: In total, 25 articles met the inclusionary criteria, including 8 studies among children/adolescents and 17 among adults. Sedentary behavior was assessed subjectively (e.g. TV viewing, computer use, reading) and objectively (e.g. accelerometry). Outcome measures included behavioral performance on various memory tasks (e.g. episodic and working memory), BDNF levels, brain volumetric measures of the temporal lobe, and hippocampal glucose metabolism. Overall, for both the child and adult studies, findings were mixed, with studies demonstrating null, inverse, and positive associations between sedentary behavior and memory. Sedentary behavior type may play a distinct role in the relationship between sedentary behavior and memory, as computer use, in particular, appeared to favorably influence memory when compared to other sedentary types (e.g. TV viewing, which showed in inverse association with memory in select studies).Conclusion: There is conflicting evidence of the relationship between sedentary behavior and memory-related outcomes among children and adults. Future studies are needed to further disentangle these complex interrelationships. Such studies should also carefully consider how physical activity may or may not moderate these relationships.

The Endocannabinoid System as a Potential Mechanism through which Exercise Influences Episodic Memory Function

Emerging research demonstrates that exercise, including both acute and chronic exercise, may influence episodic memory function. To date, mechanistic explanations of this effect are often attributed to alterations in long-term potentiation, neurotrophic production, angiogenesis, and neurogenesis. Herein, we discuss a complementary mechanistic model, suggesting that the endocannabinoid system may, in part, influence the effects of exercise on memory function. We discuss the role of the endocannabinoid system on memory function as well as the effects of exercise on endocannabinoid alterations. This is an exciting line of inquiry that should help delineate new insights into the mechanistic role of exercise on memory function.

An integrated model of acute exercise on memory function

Memory is a complex cognition that plays a critical role in daily functioning. This review discusses the dynamic effects of acute exercise on memory function, via a hypothesized exercise-memory interaction model, taking into consideration multiple memory systems and exercise parameters.

The role of astrocytes on the effects of exercise on episodic memory function

This review discusses the potential role that glial cells may play in influencing the relationship between exercise and episodic memory function. A narrative review methodology is employed. Herein, the different types of glial cells, their implications in subserving episodic memory function, and how exercise can modulate glial cell activity, particularly astrocyte functionality, are discussed. Although additional experimental work is needed, astrocytes appear to play an important role in the exercise-memory interaction. Exercise may increase astrocytic size, attenuate astrogliodegeneration, improve astrocytic aquaporin-4 expression, and increase astrocytic transporter levels. These effects, in turn, may help to increase the number of synapses that neurons form, increase the number of synaptic structures, and increase presynaptic function and postsynaptic receptor localization. Ultimately, these effects may help influence long-term potentiation and episodic memory function.

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.

Experimental effects of exercise on memory function among mild cognitive impairment: systematic review and meta-analysis

OBJECTIVE

The objective of this study was to evaluate the experimental effects of exercise on memory function among adults with mild cognitive impairment (MCI).

METHODS

A systematic review and meta-analysis were employed. Studies were identified using electronic databases, including PubMed, PsychInfo, SPORTDiscus, and Google Scholar. To be eligible for inclusion, studies had to employ an experimental design, be conducted in humans (no animal models) with mild cognitive impairment, include an exercise intervention arm (either acute exercise or chronic training), and measure memory function (any type) as the outcome measure. Comprehensive Meta-Analysis software was used to compute the standardized mean difference effect size (Cohen's d) and 95% CI using a random-effects model.

RESULTS

In total, 11 studies met our criteria, contributing to 20 effect size estimates. Among the 20 effect size estimates, 13 contributed to a short-term memory recall, with 7 contributing to a delayed/long-term memory recall. The overall weighted mean effect size was d = 0.30 (95% CI: 0.16-0.44; P < 0.001), indicating a small to medium effect of exercise on improving memory function. For the moderation analysis, there was no evidence of a moderation effect for recall duration (Q = 0.004, df(1), P = 0.95), as exercise (vs. control) demonstrated both short-term (d = 0.31; 95% CI: 0.14-0.47; P < 0.001) and long-term memory (d = 0.29; 95% CI: 0.06-0.53; P = 0.013) benefits.

CONCLUSION

Current evidence suggests that exercise may help to improve memory function among those with MCI. Safe and progressive forms of exercise should be promoted among MCI patients.

How does physical activity and different models of exercise training affect oxidative parameters and memory?

The present study investigated the chronic effects of different physical exercise and physical activity models on cognitive function, cholinergic activity, and oxidative stress markers in the cerebral cortex and hippocampus. Eighty 60-day old C57BL/6 mice were divided into the following five groups: Sedentary (SED), moderate-intensity continuous training (MICT), high-intensity interval training (HIIT), resistance training (RT), and physical activity (RW, for "running wheel"). Cognitive function (recognition and spatial memory), oxidative stress parameters, and acetylcholinesterase (AChE) activity in the cerebral cortex and hippocampus were evaluated. MICT mice exhibited enhanced recognition memory compared to SED mice (p = .046) and other exercised groups (HIIT: p < .001; RW: p = .003; RT: p < .001). The RT group showed better spatial memory compared to the SED (p = .004), MICT (p = .019), and RW (p = .003) groups. RW, MICT, HIIT, and RT training models reduced nitrites in the hippocampus compared to the SED group. RT led to a significant increase in both lipid peroxidation (p = .01) and reactive oxygen species (ROS) (p < .001) levels compared to the SED group in the hippocampus. MICT promoted an increase in catalase (CAT) activity (p = .002), while superoxide dismutase (SOD) activity was diminished by RT compared to MICT and HIIT (p = .008). In the cerebral cortex, RT increased ROS levels, but exhibited the lowest lipid peroxidation level among the groups (p < .001). The RW group showed an activity-induced increase in lipid peroxidation level compared to the SED group, and the highest level of CAT activity among all groups (p < .001). AChE activity was higher in the RT group compared to the SED, MICT, and RW groups (p = .039) in the cerebral cortex. In summary, nitrite levels in the hippocampus were decreased in all intervention groups regardless of activity or exercise model. Likewise, MICT improved recognition memory besides increasing CAT activity. We conclude that the MICT and RT protocols seem to act as oxidative stress regulators and non-pharmacological strategies to improve cognitive function.