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

A preliminary investigation of acute exercise intensity on memory and BDNF isoform concentrations

Little is known about the biological mechanisms underlying the beneficial effect of acute exercise on memory or the influence of single nucleotide polymorphisms (SNPs) on this effect. Brain-derived neurotrophic factor (BDNF) is a putative biological mechanism, and while findings from human studies are equivocal, they have neglected to assess how exercise affects individual BDNF isoform (proBDNF, mBDNF) concentrations in serum or the influence of the BDNF val66met SNP on BDNF isoform concentrations. Therefore, the objective of this study was to conduct an exploratory assessment of the effect of acute exercise intensity on memory performance and BDNF isoform concentrations relative to carrier status of the BDNF val66met SNP met allele and to provide guidance for future, fully-powered trials. Memory and BDNF isoform concentrations were assessed in three exercise groups (light intensity, vigorous intensity, and non-exercise) relative to BDNF met carrier status. Analyses revealed that BDNF isoform concentrations and memory were differentially affected by exercise intensity and BDNF met carrier status. Vigorous intensity exercise increased mBDNF, and BDNF met carriers had lower mBDNF concentration. Light intensity exercise improved memory, and over 24 h, memory was worse for BDNF met carriers. Implications from this work will help direct future mechanistic studies of the exercise-memory relationship

Motivating mature adults to be physically active

As a population, middle-aged and older adults are not meeting national guidelines for exercise. The purpose of this study was to describe factors associated with exercise adherence in an 8-month program offered as part of a research study testing the effects of exercise on cognitive performance for persons with a family history of Alzheimer’s disease (AD). After completion of the program, participants provided open-ended responses indicating their reasons for adhering to the exercise program, and they completed the Motives for Physical Activities Measure-Revised. Results indicated that adherence was tied to an interest in contributing to our understanding of AD, the opportunity to join an exercise program, perceived exercise benefits, and social support. In addition, participants reported high levels of extrinsic (fitness-related) and intrinsic (interest/enjoyment) motivation. Other possible motivating factors which emerged from day-to-day observations in the program were identified. Findings suggest directions for exercise professionals with respect to exercise adherence

Intra-vascular administration of particles to induce pulmonary hypertension, pulmonary hypertension syndrome, and ascites in animals

The invention relates to a new process for inducing pulmonary hypertension (elevated blood pressure in the pulmonary arteries) in animals, with the objective of identifying and/or eliminating susceptible individuals or families to achieve genetic improvement in agriculturally important breeds of poultry (broiler chickens and turkeys), and cattle. The invention will also be useful for animal research directed toward understanding pulmonary hypertension and its sequelae in human patients as well as in animals. Sustained pulmonary hypertension leads to pulmonary hypertension syndrome, which adversely impacts poultry production throughout the world, as well as cattle production when cattle are kept at latitudes sufficiently high to challenge blood oxygenation. In poultry, the pathophysiological progression of pulmonary hypertension syndrome leads to terminal ascites (fluid accumulation in the abdominal cavity) followed by death of the animal

Endocrine responses to sport-related brain injury in female athletes: a narrative review and a call for action

Sport-related brain injury (SRBI) occurs when a blow to the head causes the brain to move back and forth in the skull, and can lead to neuroendocrine dysfunction. Research has shown that males and females experience and recover from SRBI differently, yet most of what is known regarding diagnosis, treatment, and recovery of SRBI is based on male normative data even though females meet or exceed incidence numbers of SRBIs compared to those of males. Females also have been known to have worse outcomes and a greater number of symptoms following SRBI than males. Research is limited as to why females have worse outcomes, but sex hormones have been suggested as a potential reason. SRBI may cause a dysregulation of the hypothalamic–pituitary–gonadal (HPG) axis, which is responsible for regulating the sex hormones estrogen and progesterone. Initial research has shown that SRBI may suppress estrogen and progesterone, and the concentration of these sex hormones could be indicative of injury severity and recovery trajectory. This review discusses the sex-specific differences in SRBI and also the future direction of research that is needed in order to identify the repercussions of SRBIs for female athletes, which will eventually lead to better clinical treatment, sideline care, and recovery profiles

The Physical Activity and Alzheimer's disease (PAAD) study: Cognitive outcomes

Background: Alzheimer’s disease is a progressive disease that degrades cognitive functioning and ultimately results in death. Currently, there is no cure for Alzheimer’s disease and, hence, the identification of preventative strategies is important. Physical activity (PA) is a behavioral intervention that holds promise with respect to delaying the onset of Alzheimer’s disease. Purpose: The purpose of this study was to explore the differential cognitive benefits achieved in response to PA as a function of a person’s genetic risk for AD. Methods: Older cognitively normal adults (50–65 years) with a family history of AD (FHxAD) participated in an 8-month PA program. Cognitive performance was measured at baseline, pretest, midtest, and posttest and changes over time were assessed as a function of apolipoprotein E (APOE) status (carriers: 1–2 copies of the ?4 allele; noncarriers: 0 copies of the ?4 allele). Results: Improvements in memory were associated with PA participation irrespective of APOE ?4 carrier status. Conclusions: Future experimental studies are needed to confirm that PA causes improvements to cognitive performance in older cognitively normal adults with a FHxAD and that these improvements are equivalent for cognitively normal APOE ?4 carriers and noncarriers

The effects of low-intensity cycling on cognitive performance following sleep deprivation

This study examined the effect of 24 h of sleep deprivation on cognitive performance and assessed the effect of acute exercise on cognitive performance following sleep deprivation. Young, active, healthy adults (n = 24, 14 males) were randomized to control (age = 24.7 ± 3.7 years, BMI = 27.2 ± 7.0) or exercise (age = 25.3 ± 3.3 years, BMI = 25.6 ± 5.1) groups. Cognitive testing included a 5-min psychomotor vigilance task (PVT), three memory tasks with increasing cognitive load, and performance of the PVT a second time. On morning one, cognitive testing followed a typical night's sleep. Following 24-h of sustained wakefulness, cognitive testing was conducted again prior to and after the acute intervention. Participants in the exercise condition performed low-intensity cycling (~ 40%HRR) for 15-min and those in the control condition sat quietly on the bike for 15-min. t-Tests revealed sleep deprivation negatively affected performance on the PVT, but did not affect memory performance. Following the acute intervention, there were no cognitive performance differences between the exercise and rested conditions. We provide support for previous literature suggesting that during simple tasks, sleep deprivation has negative effects on cognitive performance. Importantly, in contrast to previous literature which has shown multiple bouts of exercise adding to cognitive detriment when combined with sleep deprivation, our results did not reveal any further detriments to cognitive performance from a single-bout of exercise following sleep deprivation

Innovative Research Exploring the Effects of Physical Activity and Genetics on Cognitive Performance in Community-Based Older Adults

Physical activity is predictive of better cognitive performance and lower risk of Alzheimer’s disease (AD). The apolipoprotein E gene (APOE) is a susceptibility gene for AD with the e4 allele being associated with a greater risk of AD. Cross-sectional and prospective research shows that physical activity is predictive of better cognitive performance for those at greater genetic risk for AD. However, the moderating role of APOE on the effects of a physical activity intervention on cognitive performance has not been examined. The purpose of this manuscript is to justify the need for such research and to describe the design, methods, and recruitment tactics used in the conductance of a study designed to provide insight as to the extent to which cognitive benefits resulting from an 8-month physical activity program are differentiated by APOE e4 status. The effectiveness of the recruitment strategies and the feasibility of recruiting APOE e4 carriers are discussed

An external focus of attention is effective for balance control when sleep-deprived

The purpose of our study was to examine if the beneficial effects of an external focus are effective for balance control when sleep-deprived. Sleep-deprived participants (27 hours awake) completed three blocks of five separate 30 second trials on a dynamic balance board. All participants were given internal, external, and control instruction. For the internal focus trials, participants focused on their feet; whereas, for the external focus trials, participants focused on the balance board. Participants’ time in balance was significantly greater during the external focus compared to the internal focus and control. These findings suggest that external focus instructions are effective when participants are sleep-deprived