Interaction between serum BDNF and aerobic fitness predicts recognition memory in healthy young adults

Role of Cardiorespiratory Fitness, Aerobic, Exercise and Sports Participation in Female Cognition: A Scoping Review : Sports, Fitness, and Cognition

BACKGROUND

The impact of cardiorespiratory fitness (CRF) on cognition is thought to be mediated by brain-derived neurotrophic factor. Aerobic exercise can increase CRF through various activities, including sports participation. The relationship between these factors in females has yet to be elucidated.

OBJECTIVE

This review aims to map the current literature on the effects of aerobic exercise, sports participation, and CRF in healthy adult females, with sub-topics of pregnancy and menstrual cycle periodicity.

METHODS

A scoping review of the literature was conducted following PRISMA guidelines and the PCC mnemonic (population, concept, and context). The following five databases were screened: CINAHL, Medline, Web of Science, SPORTDiscus, and Scopus. Eligible articles included healthy adult females, investigated aerobic exercise, sports participation or CRF, and linked outcomes to cognition. Data from included manuscripts was extracted and analyzed. Two sub-population groupings (pregnant individuals and menstrual cycle) were established to further aid the interpretation of the findings.

RESULTS

Of the 300 titles and abstracts screened, 74 were eligible for full-text screening, and 28 were included in the scoping review. Of the 28 included, 14 did not control for or report on menstrual cycle phase or sex hormones.

CONCLUSION

This scoping review found an inverse 'U' relationship between aerobic exercise and cognition, demonstrating an optimal dose of aerobic exercise to benefit cognitive functions. As estrogen may impact the relationship between CRF and neural growth factors, more research is needed on this pathway, independent of the menstrual cycle, to determine potential beneficial effects. It is currently unknown whether sports participation can independently impact cognition.

Effects of 8 weeks parent-accompanied swimming on physical capacity and intelligence in preschool children

This study aimed to explore the potential effects of 8-week parents-accompanied swimming on the physical capacity and intelligence of preschool children in China. Thirty-six boys (mean age 3.56 ± 0.27 years) were divided into three groups: the traditional physical exercise group (TP, n = 12), the accompanied swimming group (AS, n = 12) and the independent swimming group (IS, n = 12). Participants' physical capacity was assessed before and after the intervention using the following indicators: height, weight, distance of tennis ball throw, standing long jump distance, time for the 10-meter shuttle run, time for a two-legged continuous jump, sit-and-reach distance, and time on the walking balance beam. Intelligence was assessed at three points: pre-test, mid-test after 4 weeks, and post-test. Data were analyzed using a two-way repeated measures ANOVA, Bonferroni test (p < 0.05) and effect size. The time of the AS and IS groups to walk the balance beam was significantly lower than the TP group, with a difference of 1.81 s (p < 0.01, [95% CI -3.22 to -0.40], ES = 1.53) and 1.25 s (p < 0.05, [95% CI -2.66 to 0.16], ES = 0.81). At the mid-test, the IQ scores of the TP group were lower than the AS group (p < 0.05, [95% CI -12.45 to -0.96], ES = 0.89). Additionally, at post-test, the IQ scores of the TP group were significantly lower than those of both AS (p < 0.01, [95% CI -14.12 to -2.74], ES = 1.15) and IS groups (p < 0.01, [95% CI -12.53 to -3.31], ES = 1.21). Swimming enhances children's balance and IQ scores more than traditional physical exercises. Involving parents in swimming leads to a more significant increase in IQ scores within 4 weeks of initial swimming exercise.

Acute physical exercise enhances memory persistence in female rats

Memory is a complex cognitive process with distinct stages, such as acquisition, consolidation, and retrieval. The hippocampus plays a crucial role in memory consolidation and retrieval. Physical exercise (PE) has been shown to enhance memory and cognitive functions, but the available research is mainly developed with males. So, there is limited knowledge about acute PE's effects on females' memory. This study aimed to investigate the impact of acute PE on memory in female rats and explore potential sex differences in PE memory modulation. Forty-two female Wistar rats were subjected to a novel object recognition (NOR) task, with half of them undergoing a single session of 30 min of PE after the learning session (memory acquisition). Behavioral assessments showed that acute PE improved memory persistence in female rats, with increased discrimination of novel objects. Biochemical analysis revealed elevated noradrenaline levels in the hippocampus following acute PE and NOR training. Notably, the positive effects of acute PE on female rats' memory were similar to those previously observed in male rats. These findings suggest that acute PE can enhance memory in female rats and underscore the importance of considering sex differences in cognitive research. PE may offer a non-invasive strategy to promote cognitive health in both males and females.

Physical Activity and Cognitive Functioning

Neuroscience applied to motor activity is a growing area that aims to understand the effects of motor activity on the structures and functions of the Central Nervous System. Attention has been paid to this multidisciplinary field of investigation by the scientific community both because it is of great importance in the treatment of many chronic diseases and because of its potential applications in the Movement Sciences. Motor activity during a developmental age is, in fact, an indispensable tool for the physical and mental growth of children, both able-bodied and disabled. Through movement, individuals can improve their physical efficiency and promote their own better health, establish relationships with the environment and others, express themselves and their emotions, form their identity and develop cognitive processes. This literature review aims, therefore, to highlight how an adequate practice of motor activity offers extraordinary possibilities for everyone in relation to learning, from the perspective of an integral development of the person, and, consequently, can raise the awareness of those involved in the training and growth, especially the youngest, towards the educational value of motor and sports activities. According to this review, and in line with the modern neuroscientific approach toward the relationships between motor activities and cognitive functions, it is possible to claim that hypokinesia tends to inhibit learning. Therefore, it now seems more topical than ever to draw attention to the need to introduce working proposals that integrate brain-based motor activity programs into the school curriculum.

The association of aerobic and muscular fitness with cognitive impairment: Findings from a nationally representative survey

This study aimed to characterize the combined association between cardiorespiratory fitness (CRF), muscular strength, and cognitive outcomes in middle-aged and older adults from low and middle-income countries (LMICs). We analyzed cross-sectional, population-based data from adults aged 50 years or older from six LMICs. Mild cognitive impairment (MCI) was defined according to the National Institute on Aging-Alzheimer's Association criteria. Estimated CRF (eCRF) was calculated using previously validated, sex-specific equations. Handgrip strength (HS) was used as an indicator of muscular strength. We used linear and robust Poisson regression models to examine the associations between eCRF, HS, and MCI. Data from 28,339 adults (63.1 [9.5] years) were analyzed. Participants with low eCRF (PR: 1.45; 95%CI: 1.11, 1.90) and HS (PR: 1.92; 95%CI: 1.79, 2.04) were more prone to have MCI. Participants with low HS showed higher likelihood of MCI than those with preserved HS through the CRF range; however, this difference was not seen among highly fit individuals (10 METs or higher). Each 1-MET (PR: 0.77; 95%CI: 0.67, 0.86) and 5-kgf (PR: 0.63; 95%CI: 0.48, 0.79) increase was associated with a reduction in the likelihood of MCI. eCRF and HS were strongly and independently associated with MCI in middle-aged and older adults.

The Impact of Acute Mild Normobaric Hypoxia and a Single Bout of Exercise to Volitional Exhaustion on Cognitive Performance in Endurance and Strength-Trained Athletes: The role of BDNF, EP-1, Catecholamines and Lactate

The aim of the study was to examine whether a single bout of exercise to volitional exhaustion, performed under moderate normobaric hypoxia (H), would affect psychomotor performance (PP) in differently trained athletes. For this purpose, ten strength-trained (S) athletes, ten endurance-trained (E) athletes and ten healthy men leading a sedentary lifestyle as a control (C) group performed voluntarily two graded exercise tests until volitional exhaustion (EVE) under normoxia (N) and H (FiO2 = 14.7%). We measured the peripheral level of the brain derived neurotrophic factor (BDNF), choice reaction time (CRT) and the number of correct reactions (NCR) as indices of PP. Psychomotor tests were performed at rest, immediately after the EVE and 3 minutes after the EVE. Venous blood samples were collected at rest, immediately after cessation of each EVE, and 1 h after each EVE. The results showed that the EVE significantly (p < 0.05) impaired CRT under N and H, and NCR under H only in the E group. The higher WRmax in the E compared to the S and C groups was associated with a significant (p < 0.005) increase in adrenaline (A) and noradrenaline (NA). There were no significant differences between conditions (N vs. H) in the BDNF at rest and after exercise. The EVE impaired cognitive function only in the E group; higher involvement of the sympathetic nervous system, A and NA may also play a role in this phenomenon. Therefore, it can be concluded that exposure to H did not have a negative impact on CRT or NCR. Moreover, BDNF did not improve cognitive function.

Hippocampal blood flow rapidly and preferentially increases after a bout of moderate-intensity exercise in older adults with poor cerebrovascular health

Over the course of aging, there is an early degradation of cerebrovascular health, which may be attenuated with aerobic exercise training. Yet, the acute cerebrovascular response to a single bout of exercise remains elusive, particularly within key brain regions most affected by age-related disease processes. We investigated the acute global and region-specific cerebral blood flow (CBF) response to 15 minutes of moderate-intensity aerobic exercise in older adults (≥65 years; n = 60) using arterial spin labeling magnetic resonance imaging. Within 0-6 min post-exercise, CBF decreased across all regions, an effect that was attenuated in the hippocampus. The exercise-induced CBF drop was followed by a rebound effect over the 24-minute postexercise assessment period, an effect that was most robust in the hippocampus. Individuals with low baseline perfusion demonstrated the greatest hippocampal-specific CBF effect post-exercise, showing no immediate drop and a rapid increase in CBF that exceeded baseline levels within 6-12 minutes postexercise. Gains in domain-specific cognitive performance postexercise were not associated with changes in regional CBF, suggesting dissociable effects of exercise on acute neural and vascular plasticity. Together, the present findings support a precision-medicine framework for the use of exercise to target brain health that carefully considers age-related changes in the cerebrovascular system.

Associations of Physical Activity with Alzheimer’s Disease Pathologies and Cognition: The CABLE Study

Background: The associations of physical activity with Alzheimer’s disease (AD) pathologies remain controversial. Objective: To quantitatively assess the association between the frequency of physical activity with cerebrospinal fluid (CSF) biomarkers in AD and further explore the mechanism by which AD pathologies regulate the correlation between physical activity and cognition. Methods: A total of 918 participants without dementia from Chinese Alzheimer’s Biomarker and Lifestyle (CABLE) were examined in this population-based cross-sectional study. Multiple linear models were used to evaluate the associations of physical activity with CSF biomarkers and cognition. Moreover, mediation analyses were conducted to investigate the potential relationships between physical activity, AD pathologies, and cognitive function. Results: Regular physical activity was positively associated with CSF Aβ 42 (p <  0.001) and Aβ 42/40 (p <  0.001), while it was negatively associated with p-tau/Aβ 42 (p <  0.001) and t-tau/Aβ 42 (p <  0.001). Of all participants, regular physical activity was associated with increased cognitive function (p <  0.001). The interaction effect indicated that age moderated the association between physical activity frequency and CSF Aβ 42 (p = 0.014) and p-tau/Aβ 42 (p = 0.041). The impact of physical activity on cognition was mediated in part by amyloid pathologies, accounting for 4.87% to 21.56% of the total effect (p <  0.05). Conclusion: This study showed the beneficial impact of physical activity on AD pathologies and cognition in participants without dementia.

Examining the Effect of Increased Aerobic Exercise in Moderately Fit Adults on Psychological State and Cognitive Function

Regular physical exercise can decrease the risk for obesity, diabetes, and cardiovascular disease, increase life expectancy, and promote psychological health and neurocognitive functioning. Cross-sectional studies show that cardiorespiratory fitness level (VO2 max) is associated with enhanced brain health, including improved mood state and heightened cognitive performance. Interventional studies are consistent with these cross-sectional studies, but most have focused on low-fit populations. Few such studies have asked if increasing levels of physical activity in moderately fit people can significantly enhance mood, motivation, and cognition. Therefore, the current study investigated the effects of increasing aerobic exercise in moderately fit individuals on psychological state and cognitive performance. We randomly assigned moderately fit healthy adults, 25-59 years of age, who were engaged in one or two aerobic exercise sessions per week to either maintain their exercise regimen (n = 41) or increase their exercise regimen (i.e., 4-7 aerobic workouts per week; n = 39) for a duration of 3 months. Both before and after the intervention, we assessed aerobic capacity using a modified cardiorespiratory fitness test, and hippocampal functioning via various neuropsychological assessments including a spatial navigation task and the Mnemonic Similarity Task as well as self-reported measures including the Positive and Negative Affect Scale, Beck Anxiety Inventory, State-Trait Anxiety Inventory, Perceived Stress Scale, Rumination Scale, Eating Disorders Examination, Eating Attitudes Test, Body Attitudes Test, and Behavioral Regulation of Exercise Questionnaire. Consistent with our initial working hypotheses, we found that increasing exercise significantly decreased measures of negative affect, including fear, sadness, guilt, and hostility, as well as improved body image. Further, we found that the total number of workouts was significantly associated with improved spatial navigation abilities and body image as well as reduced anxiety, general negative affect, fear, sadness, hostility, rumination, and disordered eating. In addition, increases in fitness levels were significantly associated with improved episodic memory and exercise motivation as well as decreased stress and disordered eating. Our findings are some of the first to indicate that in middle-aged moderately-fit adults, continuing to increase exercise levels in an already ongoing fitness regimen is associated with additional benefits for both psychological and cognitive health.

The Effect of Endurance Training on Serum BDNF Levels in the Chronic Post-Stroke Phase: Current Evidence and Qualitative Systematic Review

Research in modern neurorehabilitation focusses on cognitive and motor recovery programmes tailored to each stroke patient, with particular emphasis on physiological parameters. The objectives of this review were to determine whether a single bout of endurance activity or long-term endurance activity regulates exercise-dependent serum brain-derived neurotrophic factor (BDNF) levels and to evaluate the methodological quality of the studies. To assess the effectiveness of endurance exercise among patients in the chronic post-stroke phase, a systematic review was performed, including searching EBSCOhost, PEDro, PubMed, and Scopus for articles published up to the end of October 2021. The PRISMA 2020 outline was used, and this review was registered on PROSPERO. Of the 180 papers identified, seven intervention studies (comprising 200 patients) met the inclusion criteria. The methodological quality of these studies was evaluated by using the Physiotherapy Evidence Database (PEDro) criteria. The effect of exercise was evaluated in four studies with a single bout of endurance activity, two studies with long-term endurance activity, and one study with a single bout of endurance activity as well as long-term endurance activity. The results of our systematic review provide evidence that endurance exercise might augment the peripheral BDNF concentration in post-stroke individuals.

Do Physical Activity, BMI, and Wellbeing Affect Logical Thinking?

We studied 6368 people (4544 women and 1824 men; aged 18–74 years). The research goal was to determine whether the Cognitive Reflection Test score (logical thinking compared with intuitive thinking) depends—and in what way it depends—on the healthy lifestyle components and emotional health-related components as well as age (18–74 years) and gender. We established that analytical vs. intuitive thinking depended on components of a healthy lifestyle, physical activity, sleep, eating habits, smoking and alcohol consumption, specificity of sporting activity, body mass index, and emotional health-related components (stress, depression, impulsivity, subjective health, emotional intelligence), as well as age and gender. We found that logical thinking was not associated with sleep, moderate-to-vigorous PA, impulsivity, subjective health, and components of a healthy lifestyle. However, logical thinking decreases with age, gender (higher in men than in women), BMI (decreases in both genders over the second degree of obesity), depression (the more severe depression in women, the worse their logical thinking), sedentary behavior (people who sat for longer periods had more difficulty solving problems), and in professional sportswomen (logical thinking is worse in professional sportswomen than in sedentary women, amateur sportswomen, or women who use gyms). Finally, we determined inverse correlations between logical thinking, emotional intelligence, and stress.

Molecular Mechanisms of Exercise and Healthspan

Healthspan is the period of our life without major debilitating diseases. In the modern world where unhealthy lifestyle choices and chronic diseases taper the healthspan, which lead to an enormous economic burden, finding ways to promote healthspan becomes a pressing goal of the scientific community. Exercise, one of humanity's most ancient and effective lifestyle interventions, appears to be at the center of the solution since it can both treat and prevent the occurrence of many chronic diseases. Here, we will review the current evidence and opinions about regular exercise promoting healthspan through enhancing the functionality of our organ systems and preventing diseases.

Exercise to spot the differences: a framework for the effect of exercise on hippocampal pattern separation in humans

Exercise has a beneficial effect on mental health and cognitive functioning, but the exact underlying mechanisms remain largely unknown. In this review, we focus on the effect of exercise on hippocampal pattern separation, which is a key component of episodic memory. Research has associated exercise with improvements in pattern separation. We propose an integrated framework mechanistically explaining this relationship. The framework is divided into three pathways, describing the pro-neuroplastic, anti-inflammatory and hormonal effects of exercise. The pathways are heavily intertwined and may result in functional and structural changes in the hippocampus. These changes can ultimately affect pattern separation through direct and indirect connections. The proposed framework might guide future research on the effect of exercise on pattern separation in the hippocampus.

Impact of Inter-Set Short Rest Interval Length on Inhibitory Control Improvements Following Low-Intensity Resistance Exercise in Healthy Young Males

The length of rest interval between sets (i.e., inter-set rest interval) is an important variable for resistance exercise program. However, the impact of the inter-set rest interval on improvements in cognitive function following resistance exercise remains unknown. In this study, we compared the effect of short rest interval (SRI) vs. long rest interval (LRI) protocols on post-exercise cognitive inhibitory control (IC) improvements induced by low-intensity resistance exercise. Twenty healthy, young males completed both SRI and LRI sessions in a crossover design. The bilateral knee extensor low-intensity resistance exercise was programed for six sets with 10 repetitions per set using 40% of one-repetition maximum. The inter-set rest interval lengths for SRI and LRI protocols were set for 1 and 3min, respectively. The color-word Stroop task (CWST) was administrated at six time points: baseline, pre-exercise, immediate post-exercise, and every 10min during the 30-min post-exercise recovery period. The levels of blood lactate, which may be an important determinant for improving IC, throughout the 30-min post-exercise recovery period were significantly higher following SRI protocol than following LRI protocol (p=0.002 for interaction effect). In line with this result, large-sized decreases in the reverse-Stroop interference score, which represent improved IC, were observed immediately after SRI protocol (d=0.94 and 0.82, respectively, vs. baseline and pre-exercise) as opposed to the moderate-sized decreases immediately after LRI protocol (d=0.62 and 0.66, respectively, vs. baseline and pre-exercise). Moreover, significant decreases in the reverse-Stroop interference score were observed from 10 to 30min after SRI protocol (all ps<0.05 vs. baseline and/or pre-exercise), whereas no such decrease was observed after LRI protocol. Furthermore, the degree of decreases in the reverse-Stroop interference score throughout the 30-min post-exercise recovery period was significantly greater in SRI protocol than in LRI protocol (p=0.046 for interaction effect). We suggest that the SRI protocol is more useful in improving post-exercise IC, potentially via greater circulating lactate levels, compared to the LRI protocol. Therefore, the inter-set rest interval length may be an important variable for determining the degree of cognitive function improvements following resistance exercise in healthy young males.

Promoting brain health through physical activity among adults exposed to early life adversity: Potential mechanisms and theoretical framework

Adverse childhood experiences such as abuse, neglect, and poverty, profoundly alter neurobehavioral development in a manner that negatively impacts health across the lifespan. Adults who have been exposed to such adversities exhibit premature and more severe age-related declines in brain health. Unfortunately, it remains unclear whether the negative effects of early life adversity (ELA) on brain health can be remediated through intervention in adulthood. Physical activity may represent a low-cost behavioral approach to address the long-term consequences of ELA on brain health. However, there has been limited research examining the impact of physical activity on brain health among adults with a history of ELA. Accordingly, the purpose of this review is to (1) review the influence of ELA on brain health in adulthood and (2) highlight evidence for the role of neurotrophic factors, hypothalamic-adrenal-pituitary axis regulation, inflammatory processes, and epigenetic modifications in mediating the effects of both ELA and physical activity on brain health outcomes in adulthood. We then propose a theoretical framework to guide future research in this area.

Sedentary patterns are associated with BDNF in patients with type 2 diabetes mellitus

PURPOSE

Exercise is beneficial to type-2 diabetes-mellitus (T2DM), and there is evidence showing that one of those benefits include a higher expression of brain-derived neurotrophic factor (BDNF), which has been implicated in improving fat oxidation and cognitive development. The deleterious effect of prolonged sedentary time (ST) on BDNF levels has never been examined in patients with T2DM. Our goal was to analyse the associations for sedentary patterns [i.e. breaks in ST per sedentary hour (BST-ST) and bouts of sedentary time (BSB) of different length] with BDNF in patients with T2DM, independent of moderate-to-vigorous physical activity (MVPA) and cardiorespiratory fitness (CRF).

METHODS

Sample included 80 patients (38 women) with T2DM (58.3 ± 7.8 years). ST and MVPA were assessed by accelerometry (ActiGraph, GT3X + model), BDNF by blood collection and plasma quantification using commercial enzyme-linked immunosorbent assay kits, and CRF was determined using a Bruce protocol to exhaustion, on a motorized treadmill.

RESULTS

Positive associations for BST-ST (β = 0.155; p = 0.007) with BDNF, and negative associations for BSB longer than 15 min with BDNF were found (β = - 0.118; p = 0.049). Neither MVPA nor cardiorespiratory fitness eliminated the associations for BST-ST with BDNF, but MVPA eradicated the associations between BSB > 15 min and BDNF.

CONCLUSIONS

Our findings suggest that interrupting ST and especially avoiding longer sedentary periods (> 15 min) may be beneficial for BDNF plasma abundance that may influence metabolic and cognitive functioning of patients with T2DM, especially for the ones presenting lower MVPA levels.

TRIAL REGISTRATION

May 5, 2017, ClinicalTrials.govID:NCT03144505.

Association between brain morphometry and aerobic fitness level and sex in healthy emerging adults

OBJECTIVE

Aerobic fitness may be beneficial for neuroanatomical structure. However, few have investigated this in emerging adults while also accounting for potential sex differences. Here we examine aerobic fitness level, sex, and their interaction in relation to cortical thickness, surface area, and volume.

METHOD

Sixty-three young adults between the ages of 16-26 were balanced for sex and demonstrated a wide range of aerobic fitness levels. Exclusion criteria included left-handedness, past-year independent Axis-I disorders, major medical/neurologic disorders, prenatal medical issues, prenatal alcohol/illicit drug exposure, or excessive substance use. Participants completed an MRI scan and a graded exercise test to volitional fatigue (VO2 max). Data analyses were run in Freesurfer and data was corrected for multiple comparisons with Monte Carlo simulations at .05.

RESULTS

Males demonstrated higher VO2 values. Higher VO2 values were statistically independently related to thinner lateral occipital, superior parietal, cuneus, precuneus, and inferior parietal regions, smaller lateral occipital volume, and larger inferior parietal surface area. Compared to females, males had larger volume in rostral anterior cingulate, lateral occipital, and superior frontal regions, and greater surface area in fusiform, inferior parietal, rostral and caudal anterior cingulate, and superior parietal regions. VO2*Sex interactions revealed higher-fit females had higher inferior parietal, paracentral, and supramarginal surface area, while lower-fit males showed larger surface area in these same regions.

CONCLUSIONS

Individuals with higher aerobic fitness performance had thinner cortices, lower volume, and larger surface area in sensorimotor regions than lower fit individuals, perhaps suggesting earlier neuromaturation in higher fit individuals. Larger surface area was associated with higher-fit females and lower-fit males. Thus both sex and aerobic fitness are important in shaping brain health in emerging adults.

Comparison Between Full-Body vs. Split-Body Resistance Exercise on the Brain-Derived Neurotrophic Factor and Immunometabolic Response

Lira, FS, Conrado de Freitas, M, Gerosa-Neto, J, Cholewa, JM, and Rossi, FE. Comparison between full-body vs. split-body resistance exercise on the brain-derived neurotrophic factor immunometabolic response. J Strength Cond Res 34(11): 3094-3102, 2020-Intense aerobic exercise seems to increase serum concentrations of brain-derived neurotrophic factor (BDNF) in conjunction with increasing lactate; however, less is known about the BDNF response to differing resistance exercise protocols. We hypothesized that full-body (FB) resistance exercise will elicit a greater increase in serum BDNF and lactate compared with split-body resistance exercise. Twelve recreationally resistance-trained men (age = 25.3 ± 5.9 years) performed 3 randomized trials of 18 sets of exercise: upper-body (UB), lower-body (LB), and FB conditions. Serum BDNF levels were assessed at rest, immediately Post-exercise, Post-1 hour, and Post-2 hours during recovery. Lactate concentration was evaluated at rest, after 9 sets, Post-exercise, Post-5, Post-10, and Post-30 minutes during recovery. In addition, interleukin (IL-6 and IL-10) and the IL-6/IL-10 ratio were calculated. Lactate concentration and total volume were greater in the FB condition compared with LB and UB (p < 0.05). For BDNF, effect sizes were largest in the LB (1.4), followed by the FB (0.75), and moderate to UB (0.33), although no significant differences were observed between conditions. There was a statistically significant relationship between lactate and BDNF only for LB condition (rho = 0.72; p = 0.013). There were a greater IL-10 Post-1 hour for FB condition compared with UB and LB (p < 0.001), and lower IL-6/IL-10 ratio in FB compared with UB (p < 0.001). Lower body induced a great BDNF response, and FB resistance exercise elicited a greater increase of serum cytokines than UB in trained men. We speculate that the volume of work performed by larger muscles has a larger influence on BDNF than overall volume.

Objective aerobic fitness level and neuropsychological functioning in healthy adolescents and emerging adults: Unique sex effects

Objective

Research suggests positive relationships between aerobic fitness and cognition in older adults; however, limited research has adequately investigated the relationship between objectively measured aerobic fitness and broad cognitive functioning in healthy adolescents and young adults without psychiatric or physical health disorders. Further, studies to date have disproportionately examined males and failed to examine sex differences. Here we examine the relationship between aerobic fitness and neuropsychological functioning in physically healthy youth and whether sex moderates these findings.

Design

Sixty-four healthy emerging adults (16-25 years-old; 32 female) underwent measurement of objective aerobic fitness (VO2 max) and neuropsychological assessment. Exclusion criteria included: left-handedness, prenatal medical issues or alcohol/illicit drug exposure, Axis-I psychiatric disorders, major medical disorders including metabolic conditions such as diabetes, hypertension, hyperlipidemia, major neurologic disorders, LOS greater than 2 min, intellectual disability or learning disability, regular substance use (e.g., greater than biweekly use of cannabis) or positive drug toxicology testing.

Method

Multiple regressions examined VO2 max, sex, sex*VO2interaction in relation to neurocognition, controlling for objectively measured body fat percentage.

Results

Prior to including body fat percentage, higher VO2 max related to improved working memory (Letter-Number Sequencing; p = .03) and selective attention (CPT-II hit response time standard error; p = .03). Aerobic fitness significantly interacted with sex, as higher-fit males had better performance on two sustained attention tasks while females did not demonstrate this pattern (CPT-II variability standard error, p = .047; Ruff 2&7 Total Speed, p = .02). Body fat percentage was positively slower cognitive flexibility (D-KEFS color-word switching/inhibition, p = .046).

Conclusions

VO2 independently predicted better working memory and selective attention. Increased aerobic fitness level related to increased performance on sustained attention tasks in males but not females. Therefore, aerobic fitness may be positively related to better cognitive functioning in physically healthy adolescents and emerging adults without metabolic conditions. Further research into factors (e.g., intensity or type of activity) that may relate to beneficial outcomes by sex are needed.

Medial temporal lobe cortical changes in response to exercise interventions in people with early psychosis: A randomized controlled trial

OBJECTIVE

Individuals with early psychosis may have prefrontal-limbic cortical deficits, which are associated with symptom severity and cognitive impairment. This study investigated the impact of an exercise intervention on fronto-temporal cortical plasticity in female participants with early psychosis.

METHODS

In a cohort of 51 female participants with early psychosis from Hong Kong, we investigated the effects of a 12-week, moderate intensity aerobic or Hatha yoga exercise trial (yoga (N = 21), aerobic (N = 18) or waitlist group (N = 12)) on cortical grey matter. Clinical assessments and structural MRI were completed pre- and post- a 12-week exercise intervention.

RESULTS

Increases in cortical volume and thickness were observed in the medial temporal cortical regions, primarily in fusiform cortical thickness (F(2, 48) = 4.221, p = 0.020, η² = 0.150) and volume (F(2, 48) = 3.521, p = 0.037, η² = 0.128) for participants with early psychosis in the aerobic arm, but not in the yoga and waitlist arms. Increased fusiform cortical thickness (ß = 0.402, p = 0.003) was associated with increased hippocampal volume for all psychosis participants. For the aerobic group only, increases in the entorhinal and fusiform temporal gyri were associated with reduced symptom severity.

CONCLUSIONS

These findings suggest exercise-induced neuroplasticity in medial temporal cortical regions occurs with aerobic exercise. These changes may be associated with improvements in psychosis symptom severity. People with early psychosis may benefit from exercise interventions, particularly aerobic exercise, as an adjunct treatment to address clinical, physical health, and neuroanatomic concerns. NIH National Library of Medicine ClinicalTrials.gov Registration #: NCT01207219https://clinicaltrials.gov/ct2/show/NCT01207219.

Exercise is medicine: a new perspective for health promotion in bipolar disorder

INTRODUCTION

Similar effects in reducing the symptoms of the mood disorder are reported in the literature compared the action of drugs and aerobic exercise sessions, demonstrating the potential of exercise in the control and mood stabilization. Therefore, there are many reasons to believe that the increased cardiorespiratory fitness (VO_2max) can be an important means of protection and a reducing potential of physical and mental damage in bipolar disorders (BD). This review will highlight the current pattern of response of exercise on the pathophysiology of BD, relating the possible mechanisms, and hypotheses based on exercises.

AREAS COVERED

The mechanism of monoaminergic action and its relationship with exercise, role of physical conditioning and increased VO_2Max on neurotrophin release, and new perspectives on long-term exercise will be reviewed.

EXPERT OPINION

The adaptations to training, although little explored in the context of BD, can induce the expression of substances that co-regulate several processes related to the pathophysiology of BD. Furthermore, high intensity interval training (HIIT) can also be adjusted to improve the physical fitness and health in patients with BD. Future research is needed to adopt a training strategy that is both time efficient and adequate for the population in question.

Neurotrophins as a reliable biomarker for brain function, structure and cognition: A systematic review and meta-analysis

Neurotrophins are signalling molecules involved in the formation and maintenance of synapses in the brain. They can cross the blood-brain barrier and be detected in peripheral blood, suggesting they may be a potential biomarker for brain health and function. In this review, the available literature was systematically searched for studies comparing peripheral neurotrophins levels with MRI and cognitive measures in healthy adults. Twenty-four studies were identified, six of which included a neuroimaging outcome. Fifteen studies measuring cognition were eligible for meta-analysis. The majority of studies measured levels of brain-derived neurotrophic factor (BDNF), with few assessing other neurotrophins. Results revealed BDNF is related to some neuroimaging outcomes, with some studies suggesting older age may be an important factor. A higher proportion of studies who had older samples observed significant effects between cognition and neurotrophin levels. When cognitive studies were pooled together in a meta-analysis, there was a weak non-significant effect between BDNF and cognitive outcomes. There was also a high level of heterogeneity between cognitive studies. Results indicated that gender was a notable source of the heterogeneity, but additional studies employing relevant covariates are necessary to better characterise the inter-relationship between circulating neurotrophins and cognition.

Current State and Future Trends: A Citation Network Analysis of the Academic Performance Field

Background: In recent years, due to its complexity and relevance, academic performance has become a controversial research topic within the health and educational field. The main purposes of this study were to analyze the links between publications and authors via citation networks, to identify the different research areas and to determine the most cited publications. Methods: The publication search was performed through the Web of Science database, using the term "Academic Performance" for a time interval from 1952 to 2019. The software used to analyze the publications was the Citation Network Explorer. Results: We found a total of 16,157 publications with 35,213 citations generated in the network, and 2018 had the highest number of publications of any year. The most cited publication was published in 2012 by Richardson et al. with a citation index score of 352. By using the clustering function, we found nine groups related to different areas of research in this field: health, psychology, psychosociology, demography, physical activity, sleep patterns, vision, economy, and delinquency. Conclusions: The citation network showed the main publications dealing with the different factors that affect academic performance, and it was determined that psychological and psychosocial factors were the most relevant.

Association of Physical Fitness with Intelligence and Academic Achievement in Adolescents

Physical fitness, intelligence and academic achievement are being studied from a multidisciplinary perspective. In this line, studies to advance our understanding of intelligence and academic achievement could be relevant for designing school-based programs. Our study analyzed the relationship between components of physical fitness including cardiorespiratory fitness, muscular strength and flexibility and general intelligence and academic achievement in adolescents. We recruited 403 adolescents (53.6% boys) with a mean age of 13.7 ± 1.2 years from a secondary school in Spain with a medium socioeconomic status, during the 2015/2016 school year. Cardiorespiratory fitness was assessed by the 20-m shuttle run, muscular strength with the standing long jump test and flexibility with the sit-and-reach test. General intelligence was measured by both the D48 and the Raven tests. School grades were used to determine academic achievement. Linear regression analyses showed that cardiorespiratory fitness was positively associated with intelligence in both the D48 (all β ≥ 0.184, p ≤ 0.016) and the Raven tests (all β ≥ 0.183, p ≤ 0.024). Muscular strength, flexibility and overall fitness were not associated with intelligence (all β ≤ 0.122, p ≥ 0.139). Cardiorespiratory fitness, muscular strength and flexibility were positively associated with academic achievement (all β ≥ 0.089, p ≤ 0.038), except muscular strength, which was not significantly associated with Spanish language or mathematics, (all β ≤ 0.050, p ≥ 0.200). Overall, cardiorespiratory fitness was positively associated with intelligence and academic achievement.

Effects of low- and high-intensity physical exercise on physical and cognitive function in older persons with dementia: a randomized controlled trial

BACKGROUND

Potential moderators such as exercise intensity or apolipoprotein-E4 (ApoE4) carriership may determine the magnitude of exercise effects on physical and cognitive functions in patients with dementia (PwD). We determined the effects of a 24-week aerobic and strength training program with a low- and high-intensity phase on physical and cognitive function.

METHODS

In an assessor-blinded randomized trial, 91 PwD (all-cause dementia, recruited from daycare and residential care facilities, age 82.3 ± 7.0 years, 59 women, Mini-Mental State Examination 20.2 ± 4.4) were allocated to the exercise or control group. In the exercise group, PwD participated in a walking and lower limb strength training program with 12 weeks low- and 12 weeks high-intensity training offered three times/week. Attention-matched control participants performed flexibility exercises and recreational activities. We assessed adherence, compliance, and exercise intensity for each session. We assessed physical (endurance, gait speed, mobility, balance, leg strength) and cognitive (verbal memory, visual memory, executive function, inhibitory control, psychomotor speed) functions with performance-based tests at baseline and after 6, 12, 18, 24, and 36 weeks (follow-up). ApoE4 carriership was determined post-intervention.

RESULTS

Sixty-nine PwD were analyzed. Their mean attendance was ~ 60% during the study period. There were no significant effects of the exercise vs. control intervention on endurance, mobility, balance, and leg strength in favor of the exercise group (Cohen's d = 0.13-0.18). Gait speed significantly improved with ~ 0.05 m/s after the high-intensity phase for exercise participants (Cohen's d = 0.41) but declined at follow-up. There were no significant effects of the exercise vs. control intervention on any of the cognitive measures (Cohen's d ~ - 0.04). ApoE4 carriership did not significantly moderate exercise effects on physical or cognitive function.

CONCLUSIONS

Exercise was superior to control activities for gait speed in our sample of PwD. However, the training effect provided no protection for mobility loss after detraining (follow-up). There were no beneficial effects of the exercise vs. control group on cognitive function. Exercise intensity moderated the effects of exercise on gait speed. ApoE4 carriership moderated the effect of exercise on global cognition only (trend level).

TRIAL REGISTRATION

Netherlands Trial Register, NTR5035. Registered on 2 March 2015.

Does brain-derived neurotrophic factor mediate the effects of exercise on memory?

Objective: Brain-derived neurotrophic factor (BDNF) has been hypothesized as a potential mechanism through which exercise may subserve memory function. The present review specifically evaluates this hypothesis.Methods: Studies were identified using electronic databases, including PubMed, PsychInfo, Sports Discus and Google Scholar.Results: In total, 52 articles met the study criteria, and among these, 36 were conducted in an animal model and 16 among humans. Among the animal experiments, 100% of them demonstrated that chronic exercise improved memory function; 97% demonstrated an exercise-induced increase in BDNF; and among the eight evaluating BDNF as a mediator, 100% provided evidence that BDNF mediated the relationship between exercise and memory. The findings in the human studies were mixed. Among the human studies, 44% demonstrated that varying exercise protocols improved memory and increased BDNF levels, and among the studies evaluating BDNF as a mediator, 40% provided evidence that BDNF mediated the relationship between exercise and memory.Conclusion: In animal models, chronic exercise training robustly increases BDNF and improves memory performance, with reasonable evidence to also suggest that BDNF may mediate the exercise-memory interaction. These interrelationships, however, are less clear among humans. Future research among humans, in particular, is needed to evaluate the extent to which BDNF may mediate the relationship between exercise and memory.

BDNF and Cortisol integrative system - Plasticity vs. degeneration: Implications of the Val66Met polymorphism

BDNF is the neurotrophin mediating pro-neuronal survival and plasticity. Cortisol (COR), in turn, is engaged in the coordination of several processes in the brain homeostasis. Stress-responsive, both factors show an integrative role through their receptor's dynamics in neurophysiology. Furthermore, the Val66Met BDNF polymorphism may play a role in this mechanism.

AIM

to investigate BDNF-COR interaction in the human neurophysiology context.

METHODS

We collected all papers containing BDNF and COR parameters or showing COR analyses in genotyped individuals in a PubMed search - full description available on PROSPERO - CRD42016050206.

DISCUSSION

BDNF and COR perform distinct roles in the physiology of the brain whose systems are integrated by glucocorticoid receptors dynamics. The BDNF polymorphism appears to have an influence on individual COR responsivity to stress. BDNF and COR play complementary roles in the nervous system where COR is a regulator of positive/negative effects. Exercise positively regulates both factors, regardless of BDNF polymorphism.

Exercise and Hippocampal Memory Systems

No medications prevent or reverse age-related cognitive decline. Physical activity (PA) enhances memory in rodents, but findings are mixed in human studies. As a result, exercise guidelines specific for brain health are absent. Here, we re-examine results from human studies, and suggest the use of more sensitive tasks to evaluate PA effects on age-related changes in the hippocampus, such as relational memory and mnemonic discrimination. We discuss recent advances from rodent and human studies into the underlying mechanisms at both the central and peripheral levels, including neurotrophins and myokines that could contribute to improved memory. Finally, we suggest guidelines for future research to help expedite well-founded PA recommendations for the public.

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.

An investigation into the relationship between cardiorespiratory fitness, cognition and BDNF in young healthy males

BACKGROUND

Recent investigations demonstrate that cardiorespiratory fitness may benefit brain health and plasticity with concurrent enhancements in cognitive performance; possibly via a brain-derived neurotrophic factor (BDNF)-regulated mechanism. While a number of studies have demonstrated an increase in BDNF concentration post exercise the relationship between BDNF, cardiorespiratory fitness and cognitive function requires further investigation.

OBJECTIVE

The present cross-sectional study assessed the association between cardiorespiratory fitness (VO₂max), cognitive performance and circulating BDNF concentration.

METHODS

Thirty-nine healthy male volunteers (mean age 21.7 ± 0.5 years) participated. Cognitive performance was measured by reaction time on a standard detection task and accuracy in a n-back and Continuous Paired Associative Learning (CPAL) task. Cardiorespiratory fitness was assessed using a standardised graded exercise test. Plasma and serum BDNF concentrations were assayed by ELISA.

RESULTS

A significant negative correlation between VO₂max and reaction time was demonstrated (p < 0.05). However VO₂max was not associated with circulating BDNF concentration, or performance in the n-back and CPAL tasks (p > 0.05).

CONCLUSIONS

Enhanced psychomotor speed was associated with higher cardiorespiratory fitness. In contrast to previous research no significant association between cardiorespiratory fitness and BDNF concentration was observed.

Aerobic Fitness Level Moderates the Association Between Cannabis Use and Executive Functioning and Psychomotor Speed Following Abstinence in Adolescents and Young Adults

OBJECTIVES

The high rate of cannabis (CAN) use in emerging adults is concerning given prior research suggesting neurocognitive deficits associated with CAN use in youth. Regular CAN use downregulates endocannabinoid activity, while aerobic exercise upregulates cannabinoid receptor 1 activity and releases endocannabinoids. Here we investigate the influence of regular CAN use on neuropsychological performance, and whether aerobic fitness moderates these effects.

METHODS

Seventy-nine young adults (37 CAN users) aged 16-26 participated. Groups were balanced for aerobic fitness level. Exclusion criteria included: left-handedness, past-year independent Axis-I disorders, major medical/neurologic disorders, prenatal issues, or prenatal alcohol/illicit drug exposure. After 3 weeks of abstinence, participants completed a neuropsychological battery and a maximal oxygen consumption test (VO2 max). Multiple regressions tested whether past-year CAN use, VO2 max, and CAN*VO2 max interaction predicted neuropsychological performance, controlling for past-year alcohol use, cotinine, gender, and depression symptoms.

RESULTS

Increased CAN use was associated with decreased performance on working memory and psychomotor tasks. High aerobic fitness level was related to better performance on visual memory, verbal fluency, and sequencing ability. CAN*VO2 max predicted performance of psychomotor speed, visual memory, and sequencing ability.

CONCLUSIONS

Following monitored abstinence, increased CAN use was associated with poorer performance in working memory and psychomotor speed. Higher aerobic fitness level moderated the impact of CAN on visual memory, executive function and psychomotor speed, as more aerobically fit CAN users demonstrated better performance relative to low-fit users. Therefore, aerobic fitness may present an affordable and efficacious method to improve cognitive functioning in CAN users. (JINS, 2019, 25, 134-145).

The Neuroprotective Effects of Exercise: Maintaining a Healthy Brain Throughout Aging

Physical activity plays an essential role in maintaining a healthy body, yet it also provides unique benefits for the vascular and cellular systems that sustain a healthy brain. While the benefit of exercise has been observed in humans of all ages, the availability of preclinical models has permitted systematic investigations into the mechanisms by which exercise supports and protects the brain. Over the past twenty-five years, rodent models have shown that increased physical activity elevates neurotrophic factors in the hippocampal and cortical areas, facilitating neurotransmission throughout the brain. Increased physical activity (such as by the voluntary use of a running wheel or regular, timed sessions on a treadmill) also promotes proliferation, maturation and survival of cells in the dentate gyrus, contributing to the process of adult hippocampal neurogenesis. In this way, rodent studies have tremendous value as they demonstrate that an 'active lifestyle' has the capacity to ameliorate a number of age-related changes in the brain, including the decline in adult neurogenesis. Moreover, these studies have shown that greater physical activity may protect the brain health into advanced age through a number of complimentary mechanisms: in addition to upregulating factors in pro-survival neurotrophic pathways and enhancing synaptic plasticity, increased physical activity promotes brain health by supporting the cerebrovasculature, sustaining the integrity of the blood-brain barrier, increasing glymphatic clearance and proteolytic degradation of amyloid beta species, and regulating microglia activation. Collectively, preclinical studies demonstrate that exercise initiates diverse and powerful neuroprotective pathways that may converge to promote continued brain health into old age. This review will draw on both seminal and current literature that highlights mechanisms by which exercise supports the functioning of the brain, and aids in its protection.

Exercise, cognition, and the adolescent brain

BACKGROUND

Few adolescents engage in the recommended levels of physical activity, and daily exercise levels tend to drastically decrease throughout adolescence. Beyond physical health benefits, regular exercise may also have important implications for the teenage brain and cognitive and academic capabilities.

METHODS

This narrative review examines how physical activity and aerobic exercise relate to school performance, cognition, and brain structure and function.

RESULTS

A number of studies have found that habitual exercise and physical activity are associated with academic performance, cognitive function, brain structure, and brain activity in adolescents. We also discuss how additional intervention studies that examine a wide range of neurological and cognitive outcomes are necessary, as well as characterizing the type, frequency, and dose of exercise and identifying individual differences that contribute to how exercise may benefit the teen brain.

CONCLUSIONS

Routine exercise relates to adolescent brain structure and function as well as cognitive performance. Together, these studies suggest that physical activity and aerobic exercise may be important factors for optimal adolescent brain development.

Physical activity, cognition and academic performance: an analysis of mediating and confounding relationships in primary school children

Background

Exploring the relationship between physical activity, cognition and academic performance in children is an important but developing academic field. One of the key tasks for researchers is explaining how the three factors interact. The aim of this study was to develop and test a conceptual model that explains the associations among physical activity, cognition, academic performance, and potential mediating factors in children.

Methods

Data were sourced from 601 New Zealand children aged 6–11 years. Weekday home, weekday school, and weekend physical activity was measured by multiple pedometer step readings, cognition by four measures from the CNS Vital Signs assessment, and academic performance from the New Zealand Ministry of Education electronic Assessment Tools for Teaching and Learning (e-asTTle) reading and maths scores. A Structured Equation Modelling approach was used to test two models of variable relationships. The first model analysed the physical activity-academic performance relationship, and the second model added cognition to determine the mediating effect of cognition on the physical activity-academic performance association. Multigroup analysis was used to consider confounding effects of gender, ethnicity and school socioeconomic decile status.

Results

The initial model identified a significant association between physical activity and academic performance (r = 0.225). This direct association weakened (r = 0.121) when cognition was included in the model, demonstrating a partial mediating effect of cognition. While cognition was strongly associated with academic performance (r = 0.750), physical activity was also associated with cognition (r = 0.138). Subgroups showed similar patterns to the full sample, but the smaller group sizes limited the strength of the conclusions.

Conclusions

This cross-sectional study demonstrates a direct association between physical activity and academic performance. Furthermore, and importantly, this study shows the relationship between physical activity and academic performance is supported by an independent relationship between physical activity and cognition. Larger sample sizes are needed to investigate confounding factors of gender, age, socioeconomic status, and ethnicity. Future longitudinal analyses could investigate whether increases in physical activity can improve both cognition and academic performance.

Taekwondo Training Improves Mood and Sociability in Children from Multicultural Families in South Korea: A Randomized Controlled Pilot Study

Purpose: Children from multicultural families face physical, social, mental, and intellectual hurdles; however, relative interventions are lacking in South Korea (hereafter Korea) in this regard. The purpose of this study was to investigate the effects of regular Taekwondo (TKD) training on physical fitness, mood, sociability, and cognitive functions in these children. Methods: This study included 30 children from multicultural families in Korea who were randomly assigned to a TKD group (n = 15) and control group (n = 15). The children in TKD group underwent 16 weeks of TKD training once a week for 60 min. Each participant underwent a basic fitness test and sociability questionnaire before and after the intervention. Furthermore, we examined the changes in the mood and cognitive function by determining the profile of mood states (POMS), and Stroop color and word test, respectively. Results: Results of the Stork test of balance were significantly higher in the TKD group after intervention (p < 0.05). In terms of sub-variables, POMS, tension, and depression scores were significantly lower (p < 0.05) after the intervention, while the vigor score was significantly higher in the intervention group than those in the control group (p < 0.05). Furthermore, sociability and ‘being left out’ score, a sub-variable of sociability, was significantly lower (p < 0.05) after the intervention, while sociability score was significantly higher (p < 0.05). Conclusions: Our findings suggest that participation in regular TKD training can be effective for balanced improvements in variables of basic fitness and that it exerts a positive effect on the mood and development of sociability.

Synergistic effects of brain-derived neurotrophic factor (BDNF) and exercise intensity on memory in the adolescent brain: a commentary

This commentary highlights the recently published study by Jeon and Ha (Environ Health Prev Med 22:27, 2017) examining the effects of exercise intensity and brain-derived neurotrophic factor (BDNF) on memory in adolescents. This 12-week training study elicited increases in BDNF and improvements in working memory during moderate- and high-intensity exercise, which may have been achieved through improved brain tissue oxygenation, nutrient delivery, and BDNF mRNA expression. These improvements highlight the positive neuroendocrinological effects of BDNF and its role as a potential candidate molecule, as a mediator of synaptic plasticity. In this commentary, we aim to highlight the strengths and potential areas of consideration of Jeon and Ha (Environ Health Prev Med 22:27, 2017). We also offer insight into the clinical implications of this study, such as advocating for exercise in healthy children and as adjunctive therapy in pathological states. This study is promising and further highlights the importance of cardiorespiratory exercise in improving physiological health and cognitive functioning in youth through the phenomenon of neuroplasticity.

The Effects of Physical Exercise and Cognitive Training on Memory and Neurotrophic Factors

This study examined the combined effect of physical exercise and cognitive training on memory and neurotrophic factors in healthy, young adults. Ninety-five participants completed 6 weeks of exercise training, combined exercise and cognitive training, or no training (control). Both the exercise and combined training groups improved performance on a high-interference memory task, whereas the control group did not. In contrast, neither training group improved on general recognition performance, suggesting that exercise training selectively increases high-interference memory that may be linked to hippocampal function. Individuals who experienced greater fitness improvements from the exercise training (i.e., high responders to exercise) also had greater increases in the serum neurotrophic factors brain-derived neurotrophic factor and insulin-like growth factor-1. These high responders to exercise also had better high-interference memory performance as a result of the combined exercise and cognitive training compared with exercise alone, suggesting that potential synergistic effects might depend on the availability of neurotrophic factors. These findings are especially important, as memory benefits accrued from a relatively short intervention in high-functioning young adults.

The positive cognitive impact of aerobic fitness is associated with peripheral inflammatory and brain-derived neurotrophic biomarkers in young adults

There is ample evidence for supporting the positive impact of aerobic fitness on cognitive function, but little is known about the physiological mechanisms. The objective of this study was to investigate whether the positive cognitive impact of aerobic fitness is associated with inflammatory and neurotrophic peripheral biomarkers in young adults aged 18 to 29years (n=87). For the objective assessment of aerobic fitness, we measured maximal oxygen uptake (VO₂max) as a parametric measure of cardiorespiratory capacity. We demonstrated that young adults with the higher levels of VO₂max performed better on computerized cognitive tasks assessing sustained attention and working memory. This positive VO₂max-cognitive performance association existed independently of confounders (e.g., years of education, intelligence scores) but was significantly dependent on resting peripheral blood levels of inflammatory (C-reactive protein, CRP) and neurotrophic (brain-derived neurotrophic factor, BDNF) biomarkers. Statistical models showed that CRP was a mediator of the effect of VO₂max on working memory. Further, BDNF was a moderator of the effect of VO₂max on working memory. These mediating and moderating effects occurred in individuals with higher levels of aerobic fitness. The results suggest that higher aerobic fitness, as measured by VO₂max, is associated with enhanced cognitive functioning and favorable resting peripheral levels of inflammatory and brain-derived neurotrophic biomarkers in young adults.

The Effects of Taekwondo Training on Peripheral Neuroplasticity-Related Growth Factors, Cerebral Blood Flow Velocity, and Cognitive Functions in Healthy Children: A Randomized Controlled Trial

Although regular Taekwondo (TKD) training has been reported to be effective for improving cognitive function in children, the mechanism underlying this improvement remains unclear. The purpose of the present study was to observe changes in neuroplasticity-related growth factors in the blood, assess cerebral blood flow velocity, and verify the resulting changes in children’s cognitive function after TKD training. Thirty healthy elementary school students were randomly assigned to control (n = 15) and TKD (n = 15) groups. The TKD training was conducted for 60 min at a rating of perceived exertion (RPE) of 11–15, 5 times per week, for 16 weeks. Brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF), and insulin-like growth factor-1 (IGF-1) levels were measured by blood sampling before and after the training, and the cerebral blood flow velocities (peak systolic [MCAs], end diastolic [MCAd], mean cerebral blood flow velocities [MCAm], and pulsatility index [PI]) of the middle cerebral artery (MCA) were measured using Doppler ultrasonography. For cognitive function assessment, Stroop Color and Word Tests (Word, Color, and Color-Word) were administered along with other measurements. The serum BDNF, VEGF, and IGF-1 levels and the Color-Word test scores among the sub-factors of the Stroop Color and Word Test scores were significantly higher in the TKD group after the intervention (p < 0.05). On the other hand, no statistically significant differences were found in any factors related to cerebral blood flow velocities, or in the Word test and Color test scores (p > 0.05). Thus, 16-week TKD training did not significantly affect cerebral blood flow velocities, but the training may have been effective in increasing children’s cognitive function by inducing an increase in the levels of neuroplasticity-related growth factors.

Pathophysiologic relationship between Alzheimer's disease, cerebrovascular disease, and cardiovascular risk: A review and synthesis

As the population ages due to demographic trends and gains in life expectancy, the incidence and prevalence of dementia increases, and the need to understand the etiology and pathogenesis of dementia becomes ever more urgent. Alzheimer's disease (AD), the most common form of dementia, is a complex disease, the mechanisms of which are poorly understood. The more we learn about AD, the more questions are raised about our current conceptual models of disease. In the absence of a cure or the means by which to slow disease progress, it may be prudent to apply our current knowledge of the intersection between AD, cardiovascular disease, and cerebrovascular disease to foster efforts to delay or slow the onset of AD. This review discusses our current understanding of the epidemiology, genetics, and pathophysiology of AD, the intersection between AD and vascular causes of dementia, and proposes future directions for research and prevention.

Functional and Structural Benefits Induced by Omega-3 Polyunsaturated Fatty Acids During Aging

BACKGROUND

Omega-3 polyunsaturated fatty acids (n-3 PUFA) are structural components of the brain and are indispensable for neuronal membrane synthesis. Along with decline in cognition, decreased synaptic density and neuronal loss, normal aging is accompanied by a reduction in n-3 PUFA concentration in the brain in both humans and rodents. Recently, many clinical and experimental studies have demonstrated the importance of n-3 PUFA in counteracting neurodegeneration and agerelated dysfunctions.

METHODS

This review will focus on the neuroprotective effects of n-3 PUFA on cognitive impairment, neuroinflammation and neurodegeneration during normal aging. Multiple pathways of n-3 PUFA preventive action will be examined.

RESULTS

Namely, n-3 PUFA have been shown to increase the levels of several signaling factors involved in synaptic plasticity, thus leading to the increase of dendritic spines and synapses as well as the enhancement of hippocampal neurogenesis even at old age. In elderly subjects n-3 PUFA exert anti-inflammatory effects associated with improved cognitive functions. Interestingly, growing evidence highlights n-3 PUFA efficacy in preventing the loss of both gray and white matter volume and integrity.

CONCLUSION

This review shows that n-3 PUFA are essential for a successful aging and appear as ideal cognitive enhancers to be implemented in nutritional interventions for the promotion of healthy aging.

Sleep extension increases IGF-I concentrations before and during sleep deprivation in healthy young men

Sleep deprivation is known to suppress circulating trophic factors such as insulin-like growth factor (IGF)-I and brain-derived neurotrophic factor (BDNF). This experiment examined the effect of an intervention involving 6 nights of extended sleep before total sleep deprivation on this catabolic profile. In a randomized crossover design, 14 young men (age range: 26–37 years) were either in an extended (EXT; time in bed: 2100–0700 h) or habitual (HAB: 2230–0700 h) sleep condition, followed by 3 days in the laboratory with blood sampling at baseline (B), after 24 h of sleep deprivation (24h-SD), and after 1 night of recovery sleep (R). In the EXT condition compared with the HAB condition, free IGF-I levels were significantly higher at B, 24h-SD, and R (P < 0.001), and those of total IGF-I at B and 24h-SD (P < 0.05). EXT did not influence growth hormone, IGF binding protein 3, BDNF, insulin, and glucose levels. The only effect of 24 h of sleep deprivation was for insulin levels, which were significantly higher after R compared with B. In a healthy adult, additional sleep over 1 week increased blood concentrations of the anabolic factor IGF-I before and during 24 h of sleep deprivation and after the subsequent recovery night without effects on BDNF. With further research, these findings may prove to be important in guiding effective lifestyle modifications to limit physical or cognitive deficits associated with IGF-I decrease with age.

The Relation Between Aerobic Fitness and Cognitive Performance

Abstract. This study aimed to assess whether brain potentials have significant influences on the relationship between aerobic fitness and cognition. Behavioral and electroencephalographic (EEG) data was collected from 48 young adults when performing a Posner task. Higher aerobic fitness is related to faster reaction times (RTs) along with greater P3 amplitude and shorter P3 latency in the valid trials, after controlling for age and body mass index. Moreover, RTs were selectively related to P3 amplitude rather than P3 latency. Specifically, the bootstrap-based mediation model indicates that P3 amplitude mediates the relationship between fitness level and attention performance. Possible explanations regarding the relationships among aerobic fitness, cognitive performance, and brain potentials are discussed.

Peripheral brain-derived neurotrophic factor is related to cardiovascular risk factors in active and inactive elderly men

Regular exercise plays an important preventive and therapeutic role in heart and vascular diseases, and beneficially affects brain function. In blood, the effects of exercise appear to be very complex and could include protection of vascular endothelial cells via neurotrophic factors and decreased oxidative stress. The purpose of this study was to identify the age-related changes in peripheral brain-derived neurotrophic factor (BDNF) and its relationship to oxidative damage and conventional cardiovascular disease (CVD) biomarkers, such as atherogenic index, C-reactive protein (hsCRP) and oxidized LDL (oxLDL), in active and inactive men. Seventeen elderly males (61-80 years) and 17 young males (20-24 years) participated in this study. According to the 6-min Åstrand-Rhyming bike test, the subjects were classified into active and inactive groups. The young and elderly active men had a significantly better lipoprotein profile and antioxidant status, as well as reduced oxidative damage and inflammatory state. The active young and elderly men had significantly higher plasma BDNF levels compared to their inactive peers. BDNF was correlated with VO2max (r=0.765, P<0.001). In addition, we observed a significant inverse correlation of BDNF with atherogenic index (TC/HDL), hsCRP and oxLDL. The findings demonstrate that a high level of cardiorespiratory fitness reflected in VO2max was associated with a higher level of circulating BDNF, which in turn was related to common CVD risk factors and oxidative damage markers in young and elderly men.