Linking brains and brawn: exercise and the evolution of human neurobiology

The hunting and gathering lifestyle adopted by human ancestors around 2 Ma required a large increase in aerobic activity. High levels of physical activity altered the shape of the human body, enabling access to new food resources (e.g. animal protein) in a changing environment. Recent experimental work provides strong evidence that both acute bouts of exercise and long-term exercise training increase the size of brain components and improve cognitive performance in humans and other taxa. However, to date, researchers have not explored the possibility that the increases in aerobic capacity and physical activity that occurred during human evolution directly influenced the human brain. Here, we hypothesize that proximate mechanisms linking physical activity and neurobiology in living species may help to explain changes in brain size and cognitive function during human evolution. We review evidence that selection acting on endurance increased baseline neurotrophin and growth factor signalling (compounds responsible for both brain growth and for metabolic regulation during exercise) in some mammals, which in turn led to increased overall brain growth and development. This hypothesis suggests that a significant portion of human neurobiology evolved due to selection acting on features unrelated to cognitive performance.     

DNA Damage and Radiosensitivity in Blood Cells from Subjects Undergoing 45 Days of Isolation and Confinement: An Explorative Study

The effect of confined and isolated experience on astronauts’ health is an important factor to consider for future space exploration missions. The more confined and isolated humans are, the more likely they are to develop negative behavioral or cognitive conditions such as a mood decline, sleep disorder, depression, fatigue and/or physiological problems associated with chronic stress. Molecular mediators of chronic stress, such as cytokines, stress hormones or reactive oxygen species (ROS) are known to induce cellular damage including damage to the DNA. In view of the growing evidence of chronic stress-induced DNA damage, we conducted an explorative study and measured DNA strand breaks in 20 healthy adults. The participants were grouped into five teams (missions). Each team was composed of four participants, who spent 45 days in isolation and confinement in NASA’s Human Exploration Research Analog (HERA). Endogenous DNA integrity, ex-vivo radiation-induced DNA damage and the rates of DNA repair were assessed every week. Our results show a high inter-individual variability as well as differences between the missions, which cannot be explained by inter-individual variability alone. The ages and sex of the participants did not appear to influence the results.     

One hundred years ago: A medical minister in Russia

ObjectivesTo evaluate cardiovascular fitness exercise in people with fibromyalgia.DesignRandomised controlled trial.SettingHospital rheumatology outpatients. Group based classes took place at a “healthy living centre.”Participants132 patients with fibromyalgia.InterventionsPrescribed graded aerobic exercise (active treatment) and relaxation and flexibility (control treatment).ResultsCompared with relaxation exercise led to significantly more participants rating themselves as much or very much better at three months: 24/69 (35%) v 12/67 (18%), P=0.03. Benefits were maintained or improved at one year follow up when fewer participants in the exercise group fulfilled the criteria for fibromyalgia (31/69 v 44/67, P=0.01). People in the exercise group also had greater reductions in tender point counts (4.2 v 2.0, P=0.02) and in scores on the fibromyalgia impact questionnaire (4.0 v 0.6, P=0.07).ConclusionsPrescribed graded aerobic exercise is a simple, cheap, effective, and potentially widely available treatment for fibromyalgia.

What is already known on this topic

Fibromyalgia is common debilitating medically unexplained condition affecting around 1% of the populationCurrent treatments are unsatisfactory and most people remain the same after several years of treatmentExercise as a treatment given by healthcare professionals in highly specialised centres is of some short term benefit

What this study adds

For people with fibromyalgia prescribed graded aerobic exercise is an effective treatment that leads to improvements in self reported health statusPrescribed exercise can be undertaken effectively in the community by personal trainers previously inexperienced in management of people with ill health     

Cycling on a Bike Desk Positively Influences Cognitive Performance

PurposeCycling desks as a means to reduce sedentary time in the office has gained interest as excessive sitting has been associated with several health risks. However, the question rises if people will still be as efficient in performing their desk-based office work when combining this with stationary cycling. Therefore, the effect of cycling at 30% Wmax on typing, cognitive performance and brain activity was investigated.MethodsAfter two familiarisation sessions, 23 participants performed a test battery [typing test, Rey auditory verbal learning test (RAVLT), Stroop test and Rosvold continuous performance test (RCPT)] with electroencephalography recording while cycling and sitting on a conventional chair.ResultsTyping performance, performance on the RAVLT and accuracy on the Stroop test and the RCPT did not differ between conditions. Reaction times on the Stroop test and the RCPT were shorter while cycling relative to sitting (p < 0.05). N200, P300, N450 and conflict SP latency and amplitude on the Stroop test and N200 and P300 on the RCPT did not differ between conditions.ConclusionsThis study showed that typing performance and short-term memory are not deteriorated when people cycle at 30% Wmax. Furthermore, cycling had a positive effect on response speed across tasks requiring variable amounts of attention and inhibition.     

Comparative analysis of preventive efficacy of different modes of locomotor training in space flight

According to the results of the experiment performed on board the International Space Station with participation of 15 Russian cosmonauts, comparative analysis of efficacy of two models of preventive measures used by the Russian members of long-term space missions is carried out: intense interval training in the aerobic–anaerobic power zone (recommended model) and continuous low-intensity exercises in the aerobic power zone of muscle activity energy supply. Interval training in space flight provided the maintenance of the level of physical performance close to the pre-flight level as indicated by the maximum running speed, physiological value of work, and the lactate level after performing the standard load. We describe putative mechanisms of counteraction to adaptive rearrangement of the propulsion system in zero gravity and expand understanding of the laws governing human body’s interaction with Earth’s gravitational field. The research results presented in this paper show the high preventive efficacy of interval training compared with regular aerobic training, which is very important now in the time of searching for means and methods of prevention of hypogravitational alterations during interplanetary missions.     

Interplay between hormones and exercise on hippocampal plasticity across the lifespan

The hippocampus is a brain structure known to play a central role in cognitive function (namely learning and memory) as well as mood regulation and affective behaviors due in part to its ability to undergo structural and functional changes in response to intrinsic and extrinsic stimuli. While structural changes are achieved through modulation of hippocampal neurogenesis as well as alterations in dendritic morphology and spine remodeling, functional (i.e., synaptic) changes can be noted through the strengthening (i.e., long-term potentiation) or weakening (i.e., long-term depression) of the synapses. While age, hormone homeostasis, and levels of physical activity are some of the factors known to module these forms of hippocampal plasticity, the exact mechanisms through which these factors interact with each other at a given moment in time are not completely understood. It is well known that hormonal levels vary throughout the lifespan of an individual and it is also known that physical exercise can impact hormonal homeostasis. Thus, it is reasonable to speculate that hormone modulation might be one of the various mechanisms through which physical exercise differently impacts hippocampal plasticity throughout distinct periods of an individual's life. The present review summarizes the potential relationship between physical exercise and different types of hormones (namely sex, metabolic, and stress hormones) and how this relationship may mediate the effects of physical activity during three distinct life periods, adolescence, adulthood, and senescence. Overall, the vast majority of studies support a beneficial role of exercise in maintaining hippocampal hormonal levels and consequently, hippocampal plasticity, cognition, and mood regulation.     

Gebruiksvriendelijkheid van computerondersteunde cognitieve training bij psychogeriatrische patiënten met lichte tot matige cognitieve functiestoornissen

Cognitive impairment associated with dementia is characterized by a continuous decline. Cognitive training is a method to train specific brain functions such as memory and attention to prevent or slow down cognitive decline. A small number of studies has shown that cognitive training on a computer has a positive effect on both cognition and mood in people with cognitive impairment. This pilot study tested if serious games could be integrated in a psychogeriatric rehabilitation center. Fourteen psychogeriatric patients participated twice weekly in cognitive training sessions on a computer. Both the participants and the facilitator reported positive interactions and outcomes. However, after five weeks only half of the sample still participated in the training. This was partly because of patient turn-over as well as incorporating this new task in the facilitators’ daily work. Fear of failure, physical limitations and rapidly decreasing cognitive function led to drop out according to the facilitator. The engagement of patients in the games and the role of the facilitator seemed essential for success, especially monitoring (and adjusting) the difficulty level of the program for every individual participant.     

Influence of exercise on serotonergic neuromodulation in the brain

Summary. Implications of exercise on serotonergic neuromodulation in the brain have been investigated in two studies. Acute paroxetine (selective serotonin (5-HT) reuptake inhibitor) administration to endurance athletes, who performed a cycle ergometer test to exhaustion at moderate intensity, reduced time to exhaustion and post exercise cognitive performance in comparison to trials with placebo or BCAA administration. Furthermore, during a 3-week moderate endurance training of sedentary males basaline values of B_max of 5-HT transporters (5-HTT) and 5-HT_2A receptors (5-HT_2AR) on isolated platelet membranes increased while plasma prolactin (PRL) concentrations decreased as well as mood and physical efficiency improved. In contrast, after an excessive training program over four weeks, well-trained endurance athletes showed no change of B_max of 5-HTT, but a decline of 5-HT_2AR density and an increase in basal plasma PRL concentration. Mood was impaired and central fatigue increased. Thus, the impact of exercise on 5-HT neurotransmission may depend on training state of athletes and extent of exertion. The theoretical background of the implication of exercise and the effect of long lasting exhaustive exercise in athletes on mental and physical efficiency or central fatigue are evaluated. The significance of the primary disturbance of central neuromodulation and dysfunction of 5-HTT, 5-HT receptor subtypes and the phosphoinositol signal transduction as well as the limited modulation capacity of the 5-HT system in overstrain are also addressed. Received December 1, 1999 / Accepted February 1, 2000     

主动运动训练和被动运动训练对人工全膝关节置换患者的随机对照研究

摘要 目的：对比主动运动训练和被动运动训练在人工全膝关节置换（TKA）患者中的应用效果。方法：选择2017年4月~2021年8月期间我院骨科收治的TKA患者65例,根据随机数字表法将患者分为主动组（主动运动训练）和被动组（被动运动训练）,各为33例和32例。对比两组生活自理能力、平衡能力、疼痛情况、膝关节功能情况、膝关节活动度和生活质量。结果：两组术后1周、术后2周Barthel指数（BI）、Berg平衡量表（BBS）、美国膝关节外科学会评分标准（KSS）评分均较术前升高,视觉疼痛模拟法（VAS）评分均较术前下降（P<0.05）。主动组BI、BBS、KSS评分高于被动组,VAS评分低于被动组（P<0.05）。两组术前、术后3 d、术后7 d被动关节活动度（PROM）、主动关节活动度（AROM）均下降后升高（P<0.05）,主动组术后3 d AROM、PROM高于被动组（P<0.05）。两组术后3个月生理职能、生理机能、一般健康、躯体疼痛、社会功能、精力、精神健康、情感职能各维度评分均升高,且主动组高于被动组（P<0.05）。结论：与被动运动训练相比,主动运动训练应用于TKA患者,可减轻患者疼痛,改善膝关节活动度及功能,改善患者生活自理能力,提高其生活质量的效果均更显著。     

Effectiveness of Different Training Programs for Physical Performance Maintenance under the Condition of Low Motor Activity

Investigations made by the World Health Organization have shown that lack of physical activity and sedentary lifestyle are among ten major causes for death and disability. Typically, studies of the negative effects of reduced physical activity and their prevention face difficulties of providing standard conditions. These issues were obviated successfully in the Mars-500 experiment on simulation of a space exploration mission. The sample of subjects consisted of six volunteers from Russia, France, Italy, and China, who were isolated in a limited space for 520 days. To prevent the negative effects of low physical activity, the volunteers performed resistive and cyclic exercises in different periods of isolation. The study was designed with two pauses in the training program. Physical performance was evaluated with an incremental loading test, maximal voluntary effort test (Russian–Austrian MDS resistive exercise system), and PWC-170 (bicycle ergometer). The level of physical performance of the subjects in this experiment never degraded to below baseline values. The proposed training system comprising different kinds of exercise ensured stability or improvement physical performance as compared with the baseline level.     

Effect of cycling exercise on lumbopelvic control performance in elite female cyclists

Objectives:The purpose of the present study is to assess the effects of an intense cycling training session on the stability of the lumbopelvic-hip complex through two dynamic exercise tests - the single-leg-deadlift (SLD) and a variation of the bird-modified dog (BD), via the OCTOcore application.Methods:Thirty-one elite female road cyclists were self-evaluated with their own smartphones, before and immediately after finishing their training sessions. Right, left and composite were measured for each exercise test.Results:There was a significant time effect on performance for both the SLB and BD tests (p<0.05; η²=0.137), and the SLD and BD tests were increased with respect to the pre-test at 15% and 17%, respectively.Conclusion:An intense cycling training session produced significant alterations in lumbopelvic behavior in the elite female cyclists. The OCTOcore application demonstrated that it was a sensitive tool in detecting these changes and it could easily be used by the cyclists themselves.     

Social Dancing and Incidence of Falls in Older Adults: A Cluster Randomised Controlled Trial

BackgroundThe prevention of falls among older people is a major public health challenge. Exercises that challenge balance are recognized as an efficacious fall prevention strategy. Given that small-scale trials have indicated that diverse dance styles can improve balance and gait of older adults, two of the strongest risk factors for falls in older people, this study aimed to determine whether social dance is effective in i) reducing the number of falls and ii) improving physical and cognitive fall-related risk factors.ConclusionsSocial dancing did not prevent falls or their associated risk factors among these retirement villages'' residents. Modified dance programmes that contain "training elements" to better approximate structured exercise programs, targeted at low and high-risk participants, warrant investigation.

Trial Registration

The Australian New Zealand Clinical Trials Registry ACTRN12612000889853     

Unexpected Dual Task Benefits on Cycling in Parkinson Disease and Healthy Adults: A Neuro-Behavioral Model

BackgroundWhen performing two tasks at once, a dual task, performance on one or both tasks typically suffers. People with Parkinson’s disease (PD) usually experience larger dual task decrements on motor tasks than healthy older adults (HOA). Our objective was to investigate the decrements in cycling caused by performing cognitive tasks with a range of difficulty in people with PD and HOAs.MethodsTwenty-eight participants with Parkinson’s disease and 20 healthy older adults completed a baseline cycling task with no secondary tasks and then completed dual task cycling while performing 12 tasks from six cognitive domains representing a wide range of difficulty.ResultsCycling was faster during dual task conditions than at baseline, and was significantly faster for six tasks (all p<.02) across both groups. Cycling speed improved the most during the easiest cognitive tasks, and cognitive performance was largely unaffected. Cycling improvement was predicted by task difficulty (p<.001). People with Parkinson’s disease cycled slower (p<.03) and showed reduced dual task benefits (p<.01) than healthy older adults.ConclusionsUnexpectedly, participants’ motor performance improved during cognitive dual tasks, which cannot be explained in current models of dual task performance. To account for these findings, we propose a model integrating dual task and acute exercise approaches which posits that cognitive arousal during dual tasks increases resources to facilitate motor and cognitive performance, which is subsequently modulated by motor and cognitive task difficulty. This model can explain both the improvement observed on dual tasks in the current study and more typical dual task findings in other studies.     

Exercise, brain, and cognition across the life span

This is a brief review of current evidence for the relationships between physical activity and exercise and the brain and cognition throughout the life span in non-pathological populations. We focus on the effects of both aerobic and resistance training and provide a brief overview of potential neurobiological mechanisms derived from non-human animal models. Whereas research has focused primarily on the benefits of aerobic exercise in youth and young adult populations, there is growing evidence that both aerobic and resistance training are important for maintaining cognitive and brain health in old age. Finally, in these contexts, we point out gaps in the literature and future directions that will help advance the field of exercise neuroscience, including more studies that explicitly examine the effect of exercise type and intensity on cognition, the brain, and clinically significant outcomes. There is also a need for human neuroimaging studies to adopt a more unified multi-modal framework and for greater interaction between human and animal models of exercise effects on brain and cognition across the life span.     

Programa de entrenamiento de memoria para mayores con alteraciones de memoria: resultados y predictores

IntroductionDeficits in memory performance in later life are frequent and well documented. There are several terms that refer to this phenomenon and the most commonly used is age associated memory impairment (AAMI). Currently, cognitive or memory training programmes are increasingly being used to treat this deficit. The Department of Health of the City of Madrid has developed a multifactorial memory training programme for older people which is carried out in 13 City Health Centres.ObjectivesTo study the effects of this programme in a sample of users aged more than 65 years with memory impairment, to determine the persistence of the results after 6 months, and to investigate predictors of results.Patients and methodThe sample was composed of 1,083 subjects who underwent memory training. The subjects were assessed before and after training and after 6 months. Among other tests, the Mini Examen Cognoscitivo (MEC), the Rivermead Behavioural Memory Test (RBMT), the Geriatric Depression Scale (GDS), and Memory Failures of Everyday (MFE) were used. The training method used (UMAM method) was developed by the Memory Unit of the City of Madrid.ResultsObjective memory improvement for the entire group was 40% (Cohen’s «d», 0.95) and 77% of the subjects improved. Seventy- five percent of the subjects improved in subjective memory functioning (Cohen’s «d», 0.64). Improvement in mood was also observed. These changes were maintained after 6 months. The predictive variables were age, MEC, GHQ and GDS scores before training, but the percentage of explained variance was very low.ConclusionsThe multifactorial memory training programme, UMAM, improves objective and subjective memory functioning in older people with memory impairment and the benefits persist after 6 months. The predictive value of the variables studied is low.     

高强度间歇训练改善认知功能及其机制研究进展

高强度间歇训练(high-intensity interval training,HIIT)己被证明是一种省时、高效的运动策略.与传统的中、低强度有氧运动相比,它可以提供类似甚至更好的健康效益.近年来一些研究表明,HIIT可作为一种有前途的运动康复疗法来改善肥胖、糖尿病、中风、痴呆等疾病引起的认知功能受损.因此,本文综...     

Effects of Beta-Alanine Supplementation on Brain Homocarnosine/Carnosine Signal and Cognitive Function: An Exploratory Study

Objectives

Two independent studies were conducted to examine the effects of 28 d of beta-alanine supplementation at 6.4 g d^-1 on brain homocarnosine/carnosine signal in omnivores and vegetarians (Study 1) and on cognitive function before and after exercise in trained cyclists (Study 2).

Methods

In Study 1, seven healthy vegetarians (3 women and 4 men) and seven age- and sex-matched omnivores undertook a brain 1H-MRS exam at baseline and after beta-alanine supplementation. In study 2, nineteen trained male cyclists completed four 20-Km cycling time trials (two pre supplementation and two post supplementation), with a battery of cognitive function tests (Stroop test, Sternberg paradigm, Rapid Visual Information Processing task) being performed before and after exercise on each occasion.

Results

In Study 1, there were no within-group effects of beta-alanine supplementation on brain homocarnosine/carnosine signal in either vegetarians (p = 0.99) or omnivores (p = 0.27); nor was there any effect when data from both groups were pooled (p = 0.19). Similarly, there was no group by time interaction for brain homocarnosine/carnosine signal (p = 0.27). In study 2, exercise improved cognitive function across all tests (P<0.05), although there was no effect (P>0.05) of beta-alanine supplementation on response times or accuracy for the Stroop test, Sternberg paradigm or RVIP task at rest or after exercise.

Conclusion

28 d of beta-alanine supplementation at 6.4g d^-1 appeared not to influence brain homocarnosine/carnosine signal in either omnivores or vegetarians; nor did it influence cognitive function before or after exercise in trained cyclists.