Benefits Of Acute Exercise Research Articles

The Benefits of Acute Exercise for Children's Cognition Are Associated with Trait Anxiety.

Children's anxiety is associated with decreased cognitive performance. One well-established behavioral intervention to transiently improve cognitive performance in children is acute aerobic exercise (AAE). Thus far, however, it is unclear whether the benefits of AAE on cognition vary based on individual differences in children's anxiety level. Therefore, we investigated whether trait anxiety levels mediate the effects of AAE on cognitive outcomes in preadolescent children. Ninety-five preadolescent children (9 to 11 yr, 41 females) underwent two experimental interventions in a random, crossover, and counterbalanced design: an exercise protocol (20 min of walking at 65% to 75% of HRpeak) and a nonexercise control (seated rest). Behavioral indices of cognitive performance (accuracy, reaction times, response time (RT) variability) were assessed before and after each intervention using a modified flanker task. The effects of each intervention on cognitive performance were calculated as pre- to postintervention differences (effect scores). These scores were first correlated with children's personal characteristics: anxiety (STAIC), sex, age, body mass index, intelligence quotient, and aerobic fitness. Significant correlations guided subsequent hierarchical regression models, which specifically tested for associations between the effects scores and anxiety levels while controlling for remaining relevant covariates. Regression analysis revealed that anxiety was a significant predictor of the effects that AAE and rest had on cognitive performance. Specifically, higher anxiety scores were associated with greater exercise-induced cognitive benefits (increased accuracy, decreased RT variability; all P < 0.05) and greater rest-induced cognitive impairments (decreased accuracy, increased RT variability; all P < 0.01). These findings suggest that children reporting higher trait anxiety might experience greater cognitive benefits from a single bout of AAE.

Effects of Cognitive and Physical Load of Acute Exercise on Inhibitory Control and Prefrontal Cortex Hemodynamics in Children.

Evidence suggests that acute exercise benefits inhibitory control, but it remains unclear how physical and cognitive load influence this ability in preadolescent children, when faced with different types of distractors. We examined their moderating effects along with changes in prefrontal cortex hemodynamics. Using a crossover design, 29 participants completed 10 min of exercise (with an interactive training wall) at 1) low physical and low cognitive load, 2) low physical and high cognitive load, 3) high physical and low cognitive load, and 4) high physical and high cognitive load in a randomized order. Before and after each condition, they performed a Standard and Affective Stroop task. During both tasks, the lateral oxygenation difference in the prefrontal cortex was measured by using functional near-infrared spectroscopy. For the Standard Stroop task, there was no effect of physical and cognitive load on performance. In contrast, exercise with low compared with high cognitive load was associated with a greater reduction of reaction time and increase in accuracy on the Affective Stroop task. This was accompanied by a decrease in lateral oxygenation difference on trials with low inhibitory control demands. Acute exercise with low compared with high cognitive demand benefits the ability to resolve emotional conflict, but the control over inhibition of nonemotional information remains unaffected. This effect of cognitive load is complemented by an increased efficiency of the left prefrontal cortex, when no emotional conflict resolution is required.

Acute exercise and children’s cognitive functioning: What is the optimal dose of cognitive challenge?

Acute bouts of exercise have the potential to benefit children’s cognition. Inconsistent evidence on the role of qualitative exercise task characteristics calls for further investigation of the cognitive challenge level in exercise. Thus, the study aim was to investigate which “dose” of cognitive challenge in acute exercise benefits children’s cognition, also exploring the moderating role of individual characteristics. In a within-subject experimental design, 103 children (Mage = 11.1, SD = 0.9, 48% female) participated weekly in one of three 15-min exergames followed by an Attention Network task. Exergame sessions were designed to keep physical intensity constant (65% HRmax) and to have different cognitive challenge levels (low, mid, high; adapted to the ongoing individual performance). ANOVAs performed on variables that reflect the individual functioning of attention networks revealed a significant effect of cognitive challenge on executive control efficiency (reaction time performances; p = .014, ƞ2p = .08), with better performances after the high-challenge condition compared to lower ones (ps < .015), whereas alerting and orienting were unaffected by cognitive challenge (ps > .05). ANOVAs performed on variables that reflect the interactive functioning of attention networks revealed that biological sex moderated cognitive challenge effects. For males only, the cognitive challenge level influenced the interactive functioning of executive control and orienting networks (p = .004; ƞ2p = .07). Results suggest that an individualized and adaptive cognitively high-challenging bout of exercise is more beneficial to children’s executive control than less challenging ones. For males, the cognitive challenge in an acute bout seems beneficial to maintain executive control efficiency also when spatial attention resources cannot be validly allocated in advance. Results are interpreted referring to the cognitive stimulation hypothesis and arousal theory.

Acute Exercise Improves Inhibitory Control but Not Error Detection in Male Violent Perpetrators: An ERPs Study With the Emotional Stop Signal Task.

Violence has been linked to the co-occurrence of cognitive dysfunction and altered activations in several brain regions. Empirical evidence demonstrated the benefits of acute exercise on motor inhibition and error detection and their neuronal processing. However, whether such effects also hold for the population with violent behaviors remains unknown. This study examined the effects of acute aerobic exercise on inhibitory control and error monitoring among violent offenders. Fifteen male violent offenders were counterbalanced into experimental protocols, which comprised a 30-min moderately aerobic exercise [60% heart rate (HR) reserve] and a 30-min reading control session. After each session, participants performed an emotional stop signal task while event-related potentials (ERPs) were recorded simultaneously. Results showed insignificant changes in ERPs components [i.e., N2, P3, error-related negativity (ERN), and error-positivity (Pe) amplitudes] and the behavioral performance in go condition, stop accuracy, and post-error adjustments by exercise. However, the current study demonstrated that the acute exercise facilitated stop signal reaction time (SSRT) when compared to the control session regardless of emotional conditions. This is the first research to exhibit the improvements in inhibitory performance by acute exercise for violent offenders. Most importantly, this effect was independent of affective settings, expanding the existing knowledge of the influences of acute exercise on cognition. Our findings implicate the perspective of acute exercise for clinical and correctional practices.

Effect of Exercise on Brain Health: The Potential Role of Lactate as a Myokine.

It has been well established in epidemiological studies and randomized controlled trials that habitual exercise is beneficial for brain health, such as cognition and mental health. Generally, it may be reasonable to say that the physiological benefits of acute exercise can prevent brain disorders in late life if such exercise is habitually/chronically conducted. However, the mechanisms of improvement in brain function via chronic exercise remain incompletely understood because such mechanisms are assumed to be multifactorial, such as the adaptation of repeated acute exercise. This review postulates that cerebral metabolism may be an important physiological factor that determines brain function. Among metabolites, the provision of lactate to meet elevated neural activity and regulate the cerebrovascular system and redox states in response to exercise may be responsible for exercise-enhanced brain health. Here, we summarize the current knowledge regarding the influence of exercise on brain health, particularly cognitive performance, with the underlying mechanisms by means of lactate. Regarding the influence of chronic exercise on brain function, the relevance of exercise intensity and modality, particularly high-intensity interval exercise, is acknowledged to induce “metabolic myokine” (i.e., lactate) for brain health.

Acute exercise effects on inhibitory control and the pupillary response in young adults

Previous research has established an impact of acute exercise on cognitive performance, which has inspired investigations into neurobiological mechanisms that may underlie the observed benefits. Pupillary responses have been posited to reflect activation of such underlying neurobiological mechanisms. The current study recruited healthy young adults to investigate the effects of a single bout of moderate-to-vigorous intensity aerobic exercise on subsequent performance and pupillary responses during an inhibitory control task. Results showed that an acute bout of exercise was related to shorter reaction times and increased tonic pupil dilation during an inhibitory control task. Although pupillary responses did not mediate the acute exercise effect on inhibitory control, higher cardiorespiratory fitness was associated with greater phasic pupil dilation following exercise relative to seated rest. The current study supported the plausibility of the pupillary response as a marker of LC-NE system activation that is sensitive to acute exercise. Whether pupillary responses could account for transient benefits of acute exercise on brain and cognition remains unclear.

Sympathetic Nervous System and Exercise Affects Cognition in Youth (SNEACY): study protocol for a randomized crossover trial

BackgroundThere is an increasing prevalence of physical inactivity during childhood, which is associated with a variety of health problems. However, the mechanisms by which acute exercise benefits cognition in childhood remains unknown. Here we describe the protocol for a randomized crossover trial called SNEACY (Sympathetic Nervous System & Exercise Affects Cognition in Youth), a study designed to better understand mechanisms linking acute exercise and cognition in 9–10-year-old healthy, cognitively normal children.MethodsChildren from the Greater Boston, MA region will be recruited to participate in this single center study. A randomized crossover design will be utilized, such that participants will act as their own controls, through initial randomization to condition assignment and condition counterbalancing across participants. One hundred three children will participate in three randomized acute interventions: moderate intensity treadmill exercise (20 min, 70–75% of their maximal heart rate), seated rest (20 min), and a Trier Social Stress Test for Children (14 min). These visits will occur on 3 three separate days, approximately 5–8 days apart. Before and after each intervention, children complete a variety of cognitive tasks measuring attentional inhibition while their neuroelectric activity is recorded. Variables of interest include EEG data, accuracy and reaction time, academic achievement, and salivary alpha amylase. Academic achievement is also assessed following interventions. In addition, children provide passive drool samples throughout the interventions to measure various biomarkers that may explain the acute exercise benefit on cognition.DiscussionThe results from this study could influence educational and public health recommendations to enhance cognition and learning in pre-adolescent children.Trial registrationClinicalTrials.gov NCT03592238. Registered on 19 July 2018

Use of Stroop Test for Sports Psychology Study: Cross-Over Design Research.

Background: In sports psychology research, the Stroop test and its derivations are commonly used to investigate the benefits of exercise on cognitive function. The measures of the Stroop test and the computed interference often have different interclass correlation coefficients (ICC). However, the ICC is never reported in cross-over designs involving multiple variances associated with individual differences.Objective: We investigated the ICC of the Stroop neutral and incongruent tests and interference (neutral test—incongruent test), and reverse Stroop task using the linear mixed model.Methods: Forty-eight young adults participated in a cross-over design experiment composed of 2 factors: exercise mode (walking, resistance exercise, badminton, and seated rest as control) and time (pre- and post-tests). Before and after each intervention, participants completed the Stroop neutral and incongruent, and the reverse-Stroop neutral and incongruent tests. We analyzed for each test performance and interference and calculated ICC using the linear mixed model.Results: The linear mixed model found a significant interaction of exercise mode and time for both the Stroop and reverse-Stroop tasks, suggesting that exercise mode influences the effect of acute exercise on inhibitory function. On the other hand, there was no significant effect of exercise mode for both the Stroop and reverse-Stroop interference. The results also revealed that calculating both the Stroop and reverse-Stroop interference resulted in smaller ICCs than the ICCs of the neutral and incongruent tests for both the Stroop and reverse-Stroop tasks.Conclusion: The Stroop and reverse-Stroop interferences are known as valid measures of the inhibitory function for cross-sectional research design. However, to understand the benefits of acute exercise on inhibitory function comprehensively by cross-over design, comparing the incongruent test with the neutral test also seems superior because these tests have high reliability and statistical power.

Daily Step Count and Postprandial Fat Metabolism.

Two benefits of acute exercise are the next day's lowering of the postprandial plasma triglyceride response to a high-fat meal and increased fat oxidation. However, if activity levels (daily steps) are very low, these acute adaptations to exercise do not occur. This phenomenon has been termed "exercise resistance." This study sought to systematically reduce daily step number and identify the range of step counts that elicit "exercise resistance." Ten participants completed three, 5-d trials in a randomized, crossover design with differing levels of step reduction. After 2 d of controlled activity, participants completed 2 d of LOW, LIMITED, or NORMAL steps (2675 ± 314, 4759 ± 276, and 8481 ± 581 steps per day, respectively). Participants completed a 1-h bout of running on the evening of the second day. High-fat tolerance tests were performed on the next morning, and postprandial responses were compared. After LOW and LIMITED, postprandial incremental area under the curve (AUC) of plasma triglyceride was elevated 22%-23% compared with NORMAL (P < 0.05). Whole body fat oxidation was also significantly lower (16%-19%, P < 0.05, respectively) in LOW and LIMITED compared with NORMAL. No significant differences were found between LOW and LIMITED. Two days of step reduction to approximately 2500-5000 steps per day in young healthy individuals impairs the ability of an acute bout of exercise to increase fat oxidation and attenuate postprandial increases in plasma triglycerides. This suggests that "exercise resistance" occurs in individuals taking approximately 5000 or fewer steps per day, whereas 8500 steps per day protects against exercise resistance in fat metabolism. It seems that fat metabolism is influenced more by the inhibitory effects of inactivity than by the stimulating effects derived from 1 h of moderate-intensity running.

Acute exercise, memory, and neural activation in young adults

Acute exercise benefits memory, and the temporal placement of exercise relative to exposure can affect the magnitude of benefits observed. Although the temporal placement appears to be important, there is a limited understanding as to how cognitive benefits in response to acute exercise are achieved. Hence, we conducted a two-part study including a behavioral study and a follow-up functional magnetic resonance imaging (fMRI) study to advance our understanding of the potential role of the effects of exercise on memory and neural activation. For Study One, we assessed the effect of acute exercise on memory in young adults. Participants were randomized to exercise before exposure for 20 min (before only, BO), after exposure for 20 min (After Only, AO), before and after exposure for 10 min at each time (before and after, BA), or to receive no exercise (No-exercise Control, NC). Similar to previous findings, any exercise prior to exposure (BO, BA) benefited some aspects of memory performance. Interestingly, the more consistent and larger benefits were seen with a shorter duration of exercise both before and after exposure (BA). Study Two replicated the methods of Study One comparing the BA condition (which had the most robust benefits) to the NC condition while collecting fMRI data during the memory task. Analyses assessed condition differences of activation during encoding and recall. There were no condition differences during memory encoding, however there was a condition effect on activation in occipito-temporal regions during the memory recall trials. Consistent with previous research, exercise appears to benefit memory with some exercise prior to exposure being important for the benefits achieved. Further, exercise affects neural activation and the results appear complementary to the behavior findings. Future research should use a within-subjects design to control for heterogeneity in behavior and neural activation.

Exercise-Induced Improvements in Postprandial Glucose Response Are Blunted by Pre-Exercise Hyperglycemia: A Randomized Crossover Trial in Healthy Individuals.

BackgroundExercise improves glycemic control but the magnitude, and in some cases, the direction of this effect is variable. Ambient hyperglycemia has been implicated in this exercise response heterogeneity. The current study investigated whether pre-exercise hyperglycemia directly impacts the effect of exercise on glycemic control.MethodsTwelve healthy normal glucose-tolerant males completed four trials in a randomized, crossover design. Each trial consisted of 24-h pre-intervention monitoring, a 7-h intervention, and 24-h post-intervention monitoring. Glycemic control was measured throughout the study by continuous glucose monitoring. The four interventions were no exercise (CON) or 45 min of cycling exercise (70%HRmax) preceded by 3.5 h of either normoglycemia (NG-Ex), steady-state hyperglycemia induced by constant glucose infusion (HG-Ex) or fluctuating glycemia induced by repeated glucose bolus infusions (FG-Ex).ResultsPhysical activity and diet were similar between trials, and energy expenditure during exercise was matched between exercise trials (all P > 0.05). Mean glucose during the 3.5 h ± infusion period was higher in HG-Ex (mean ± SEM; 7.2 ± 0.4 mmol/L) and FG-Ex (7.3 ± 0.3 mmol/L) compared to CON (4.8 ± 0.2 mmol/L) and NG-Ex (5.0 ± 0.2 mmol/L) trials (P < 0.01). Glycemic variability was greatest in FG-Ex (P < 0.01). Following the interventions, the postprandial glucose response (iAUC) was reduced by exercise in NG-Ex compared to CON (321.1 ± 38.6 vs. 445.5 ± 49.7 mmol/L.8h, P < 0.05, d=0.81). This benefit was blunted when exercise was preceded by steady-state (HG-Ex, 425.3 ± 45.7 mmol/L.8h) and fluctuating (FG-Ex, 465.5 ± 39.3 mmol/L.8h) hyperglycemia (both P > 0.05 vs. CON).ConclusionPre-exercise hyperglycemia blunted the glucoregulatory benefits of acute exercise upon postprandial glucose response, suggesting that exposure to hyperglycemia contributes to exercise response heterogeneity.Clinical Trial RegistrationClinicalTrials.gov, identifier NCT03284216.

Effects of intensity-matched exercise at different intensities on inflammatory responses in able-bodied and spinal cord injured individuals

Objective: To compare the effects of intensity-matched acute exercise at different intensities on proinflammatory and anti-inflammatory cytokines between able-bodied (AB) and spinal cord injured (SCI) individuals. Design: Non-Randomized Controlled Trial. Setting: Community settings in São Paulo – Brazil. Participants: Eight AB and nine SCI paraplegic. Interventions: Participants underwent three exercise sessions at different relative intensities: at ventilatory threshold 1 intensity (VT1), 15% below VT1, and 15% above VT1. Similar energy expenditures were established from exercises with different intensities for each volunteer. The AB group was tested on a conventional treadmill, whereas the SCI group was tested on a treadmill adapted for wheelchair use. Blood samples were collected at baseline, immediately after, and 30 min after the exercise sessions. Outcome measures: Interleukin 1 receptor antagonist, interleukin 1 beta, interleukin 2, interleukin 4, interleukin 6, interleukin 10 and tumoral necrosis factor alpha were measured. Results: When groups were compared, interleukin – 2 was found higher, whereas interleukin – 4 and interleukin – 10 were found lower in the SCI group at all collection times in the three exercise intensities (all P < 0.05). Interleukin – 1 receptor antagonist was found higher immediately after exercise at VT1, 15% above VT1 and 30 min after 15% below VT1 in the AB group (all P < 0.05). In the AB group, an increase in interleukin – 6 immediately after the exercise at VT1 compared with baseline was found (P = 0.01). Conclusion: Individuals with SCI may have to perform physical exercise at a higher volume or energy expenditure than AB individuals to obtain similar anti-inflammatory benefits of acute exercise. Trial registration: Uniform Trial Number identifier: U1111-1232-8142.

Effects of a Brief Stair-Climbing Intervention on Cognitive Performance and Mood States in Healthy Young Adults.

ObjectivePrevious studies focused on the benefits of acute exercise on cognition and mood have mostly used specialized laboratory-based equipment, thus little is known about how such protocols generalize to naturalistic settings. Stair climbing is a simple and readily accessible means of exercise that can be performed in naturalistic settings (e.g., at home or at the workplace). In the present study we examined the effects of stair-climbing intervals on subsequent cognitive performance and mood in healthy young adults.MethodThirty-two undergraduate students (Mage = 19.4 years, SD = 1.3; 21 females) completed a controlled randomized crossover trial with session order counterbalanced across participants. Participants visited the lab on two occasions, one week apart, and completed one control session (no exercise) and one stair-climbing session (3 × 1 min stair-climbing intervals) with cognitive performance and mood assessed at the end of each session.ResultsRepeated measures ANCOVA revealed that males (Hedges’ gav = 0.45) showed better switching performance following the stair climbing but females (Hedges’ gav < 0.03) did not. Participants felt more energetic (Hedges’ gav = 1.05), less tense (Hedges’ gav = 0.61), and less tired (Hedges’ gav = 0.43) following the stair climbing. In addition, higher exercise intensity during the stair climbing predicted better subsequent switching performance and higher energetic ratings.ConclusionThese findings indicate that short bouts of stair climbing in a naturalistic setting can induce cognitive benefits for more challenging tasks, albeit only in males, indicating a sex-specific effect. Short bouts of stair climbing can be a practical approach to increase feelings of energy in daily life.

Beneficial Effects of Acute Exercise on Executive Function in Adolescents.

Background: Evidence supports that a single session of exercise has benefits for cognitive performance following exercise. Although the vast majority of research has been conducted with young adults, very few studies to date have tested these effects in adolescents (high school aged students). As executive function (EF) develops through late adolescence and into young adulthood, it is important to assess the extent to which acute exercise benefits EF in adolescents. The primary purpose of this study was to assess the effect of moderate-intensity acute exercise on subsequent EF performance in this population. Methods: Healthy high school students (N = 22; age: 15.90 [0.29]y) volunteered to participate in the study. Using a within-subjects design with order of conditions randomized and counterbalanced, participants performed the Stroop Test, the Symbol Digit Modalities Test, and the Tower of London Test following control and following exercise with sessions performed on different days. Results: Exercise resulted in significant benefits for Stroop Color, Stroop Color-Word tests, Symbol Digit Modalities Test, Tower of London total moves, and Tower of London total excess moves. Conclusions: These results provide an important extension to the literature by confirming that 20 minutes of moderate-intensity exercise benefits EF performance in high school students.

Effects of Acute Aerobic Exercise on Cognition and Constructs of Decision-Making in Adults With and Without Hypertension.

Hypertension accelerates brain aging, resulting in cognitive dysfunction with advancing age. Exercise is widely recommended for adults with hypertension to attenuate cognitive dysfunction. Whether acute exercise benefits cognitive function in this at-risk population is unknown. The purpose of this study was to compare the effects of acute aerobic exercise on cognitive function in 30 middle-aged hypertensive (HTN) and 30 age, sex, and body mass index (BMI)-matched non-HTN adults (56 ± 6 years, BMI 28.2 ± 2.9 kg/m2; 32 men). Subjects underwent cognitive testing pre/post 30-min cycling (≈55% peak oxygen consumption). Cognition was assessed using standard metrics of accuracy and reaction time (RT) across memory recognition, 2-back, and Flanker tasks. Behavioral data was further analyzed using drift-diffusion modeling to examine underlying components of decision-making (strength of evidence, caution, bias) and RT (non-decision time). Exercise elicited similar changes in cognitive function in both HTN and non-HTN groups (p > 0.05). Accuracy was unaltered for Flanker and 2-back tasks, while hits and false alarms increased for memory recognition post-exercise (p < 0.05). Modeling results indicated changes in memory hits/false alarms were due to significant changes in stimulus bias post-exercise. RT decreased for Flanker and memory recognition tasks and was driven by reductions in post-exercise non-decision time (p < 0.05). Our data indicate acute exercise resulted in similar, beneficial cognitive responses in both middle-age HTN and non-HTN adults, marked by unaltered task accuracy, and accelerated RT post-exercise. Additionally, drift-diffusion modeling revealed that beneficial acceleration of cognitive processing post-exercise (RT) is driven by changes in non-decision components (encoding/motor response) rather than the decision-making process itself.

Once is enough for acute exercise benefits on insulin sensitivity.

Once is enough for acute exercise benefits on insulin sensitivity.

The Effect of Acute Exercise on Encoding and Consolidation of Long-Term Memory.

Evidence supports that acute exercise benefits long-term memory. However, it is unclear whether these effects are due to benefits to encoding or consolidation. The purpose of this study was to more effectively isolate encoding and consolidation to advance our understanding of the specific nature of the effects of exercise on long-term memory. Using a within-subject design, participants completed a control session (no exercise), an encoding and consolidation condition (exercise prior to exposure to the memory task, E + C), and a consolidation condition (exercise following exposure). The exercise was 30min of moderate-intensity cycling. Memory was assessed using the Rey Auditory Verbal Learning Test with recall assessed at 60min and recall and recognition assessed at 24hr. Results showed that the E + C condition had significantly better recall at 60min and 24hr than the no-exercise condition. This provides additional evidence that acute exercise benefits encoding more than consolidation.

Evidence for improved memory from 5\xa0minutes of immediate, post-encoding exercise among women

Memories consolidate over time, with one consequence being that what we experience after learning can influence what we remember. In these experiments, women who engaged in 5 minutes of low-impact exercise immediately after learning showed better recall for paired associations than did women who engaged in a non-exercise control activity. In experiments 1 and 2, this benefit was apparent in a direct comparison between exercise and non-exercise groups. In experiment 3, it was reflected in a weak, positive correlation between memory performance and exercise-induced change in heart rate. In experiment 4, similar patterns emerged, although they fell short of statistical significance. Such memorial benefits did not emerge among male participants. In experiment 1, half the participants alternatively engaged in an equivalent period of exercise prior to learning, with no benefits for retention of the learned material, suggesting that the memorial benefits of exercise-induced arousal may reflect a specific impact on post-learning processes such as memory consolidation. A meta-analysis across the experiments revealed a reliable benefit of post-learning exercise among women. Variation in the strength of the effect between experiments is consistent with a literature suggesting small but reliable benefits of acute exercise on cognitive performance.

Abstract 58: Extracellular RNA Response to Acute Exercise

The benefits of acute exercise on distant organs (including the neurocognitive system) have been recognized, suggesting existence of biomarkers that mediate exercise benefits in target organs. Extracellular RNAs (ex-RNAs) are RNA molecules stable in circulation, capable of regulating gene expression across multiple target organs at a distance. In 26 individuals without clinical cardiovascular disease (myocardial infarction or heart failure), we performed small non-coding RNA sequencing (RNA-seq) from plasma before and after symptom-limited treadmill exercise, with validation of selected microRNAs (miRNAs) in pulmonary arterial blood from 59 individuals referred for cardiopulmonary exercise testing. Acute exercise produced widespread shifts in the plasma ex-RNA transcriptome, with a host of novel ex-RNA subtypes with unknown function (e.g., yRNAs). miR-181b (involved in silencing of NFkB-mediated inflammation in obesity and vascular disease) was significantly increased at peak exercise (relative to rest) in both our discovery (2.3-fold increase after exercise, P=8.46x10 -11 ) and validation cohort (P=0.02). In a mouse model of acute exercise, we found that skeletal muscle miR-181b expression increased in young but not old mice after exercise, with a corresponding reduction in miR-181b mRNA targets. These results provide the first unbiased demonstration of diversity in ex-RNA release after acute exercise in humans, and suggest anti-inflammatory benefits of acute exercise may be mediated in part by circulating non-coding RNAs.

The Effects of Acute Exercise on Memory and Brain-Derived Neurotrophic Factor (BDNF).

Acute exercise benefits cognition, and some evidence suggests that brain-derived neurotrophic factor (BDNF) plays a role in this effect. The purpose of this study was to explore the dose-response relationship between exercise intensity, memory, and BDNF. Young adults completed 3 exercise sessions at different intensities relative to ventilator threshold (Vt) (VO2max, Vt - 20%, Vt + 20%). For each session, participants exercised for approximately 30 min. Following exercise, they performed the Rey Auditory Verbal Learning Test (RAVLT) to assess short-term memory, learning, and long-term memory recall. Twenty-four hours later, they completed the RAVLT recognition trial, which provided another measure of long-term memory. Blood was drawn before exercise, immediately postexercise, and after the 30-min recall test. Results indicated that long-term memory as assessed after the 24-hr delay differed as a function of exercise intensity with the largest benefits observed following maximal intensity exercise. BDNF data showed a significant increase in response to exercise; however, there were no differences relative to exercise intensity and there were no significant associations between BDNF and memory. Future research is warranted so that we can better understand how to use exercise to benefit cognitive performance.