The short-term boost our brains get after we do exercise persists throughout the following day, suggests a new study led by UCL (University College London) researchers.

Previous research in a laboratory setting has shown that people’s cognitive performance improves in the hours after exercise, but how long this benefit lasts is unknown.

The new study, published in the International Journal of Behavioral Nutrition and Physical Activity, found that, on average, people aged 50 to 83 who did more moderate to vigorous physical activity than usual on a given day did better in memory tests the day after.

Less time spent sitting and six hours or more of sleep were also linked to better scores in memory tests the next day.

More deep (slow-wave*) sleep also contributed to memory function, and the research team found this accounted for a small portion of the link between exercise and better next-day memory.

The research team looked at data from 76 men and women who wore activity trackers for eight days and took cognitive tests each day.

Lead author Dr Mikaela Bloomberg (UCL Institute of Epidemiology & Health Care) said: “Our findings suggest that the short-term memory benefits of physical activity may last longer than previously thought, possibly to the next day instead of just the few hours after exercise. Getting more sleep, particularly deep sleep, seems to add to this memory improvement.

“Moderate or vigorous activity means anything that gets your heart rate up – this could be brisk walking, dancing or walking up a few flights of stairs. It doesn’t have to be structured exercise.

“This was a small study and so it needs to be replicated with a larger sample of participants before we can be certain about the results.”

In the short term, exercise increases blood flow to the brain and stimulates the release of neurotransmitters such as norepinephrine and dopamine which help a range of cognitive functions.

These neurochemical changes are understood to last up to a few hours after exercise. However, the researchers noted that other brain states linked to exercise were more long-lasting. For instance, evidence suggests exercise can enhance mood for up to 24 hours.

A previous study, published by a separate research team in 2016, also found more synchronised activity in the hippocampus (a marker of increased hippocampal function, which facilitates memory function) for 48 hours after high-intensity interval training (HIIT) cycling.  

Co-author Professor Andrew Steptoe (UCL Institute of Epidemiology & Health Care) said: “Among older adults, maintaining cognitive function is important for good quality of life, wellbeing, and independence. It’s therefore helpful to identify factors that can affect cognitive health on a day-to-day basis.

“This study provides evidence that the immediate cognitive benefits of exercise may last longer than we thought. It also suggests good sleep quality separately contributes to cognitive performance.

“However, we can’t establish from this study whether these short-term boosts to cognitive performance contribute to longer term cognitive health and though there is plenty of evidence to suggest physical activity might slow cognitive decline and reduce dementia risk, it’s still a matter of some debate.”

For the new study, the researchers looked at data from wrist-worn activity trackers to determine how much time participants spent being sedentary, doing light physical activity, and doing moderate or vigorous physical activity. They also quantified sleep duration and time spent in lighter (rapid eye movement, or REM) sleep and deeper, slow-wave sleep.

In looking at the links between different types of activity and next-day cognitive performance, the research team adjusted for a wide variety of factors that might have distorted the results, including the amount of moderate or vigorous physical activity that participants did on the day of the tests.

They also accounted for participants’ average levels of activity and sleep quality across the eight days they were tracked, as participants who are habitually more active and typically have higher-quality sleep perform better in cognitive tests.

The team found that more moderate or vigorous physical activity compared to a person’s average was linked to better working memory and episodic memory (memory of events) the next day. More sleep overall was linked to improved episodic and working memory and psychomotor speed (a measure of how quickly a person detects and responds to the environment). More slow-wave sleep was linked to better episodic memory.

Conversely, more time spent being sedentary than usual was linked to worse working memory the next day.

The study is among the first to evaluate next-day cognitive performance using a “micro-longitudinal” study design where participants were tracked going about their normal lives rather than having to stay in a lab.

Among the study limitations, the researchers noted that the participants were a cognitively healthy group, meaning the results might not be true for people who have neurocognitive disorders.

The study involved researchers from the UCL Institute of Epidemiology & Health Care, UCL Division of Surgery & Interventional Science and the University of Oxford, and received funding from the UK’s Economic and Social Research Council (ESRC).

*Slow-wave sleep was given its name based on the characteristic brain waves that can be observed during this stage of sleep. It is deep, restorative sleep, where a person’s heart rate slows and blood pressure decreases.

Aerobic training is known to regulate blood pressure more effectively when practiced in the evening than in the morning. Now, researchers conducted a study of elderly patients at the University of São Paulo’s School of Physical Education and Sports (EEFE-USP) in Brazil, and they concluded that evening exercise is better for blood pressure regulation thanks to improved cardiovascular control by the autonomic nervous system via a mechanism known as baroreflex sensitivity.

An article on this study, “Evening but not morning aerobic training improves sympathetic activity and baroreflex sensitivity in elderly patients with treated hypertension”, was published in the The Journal of Physiology.

“There are multiple mechanisms to regulate blood pressure, and although morning training was beneficial, only evening training improved short-term control of blood pressure by enhancing baroreflex sensitivity. This is important because baroreflex control has a positive effect on blood pressure regulation, and there aren’t any medications to modulate the mechanism,” Leandro Campos de Brito, first author of the article, said.

In the study, 23 elderly patients diagnosed and treated for hypertension were randomly allocated into two groups: morning training and evening training. Both groups trained for ten weeks on a stationary bicycle at moderate intensity, with three 45-minute sessions per week.

Key cardiovascular parameters were analyzed, such as systolic and diastolic blood pressure, and heart rate after ten minutes’ rest. The data was collected before and at least three days after the volunteers completed the ten weeks of training. 

The researchers also monitored mechanisms pertaining to the autonomic nervous system (which controls breathing, heart rate, blood pressure, digestion, and other involuntary bodily functions), such as muscle sympathetic nerve activity (which regulates peripheral blood flow via contraction and relaxation of blood vessels in muscle tissue) and sympathetic baroreflex sensitivity (assessing control of blood pressure via alterations to muscle sympathetic nerve activity).

In the evening training group, all four parameters analyzed were found to improve: systolic and diastolic blood pressure, sympathetic baroreflex sensitivity, and muscle sympathetic nerve activity. In the morning training group, no improvements were detected in muscle sympathetic nerve activity, systolic blood pressure or sympathetic baroreflex sensitivity.

Evening training was more effective in terms of improving cardiovascular autonomic regulation and lowering blood pressure. This can be partly explained as due to an improvement in baroreflex sensitivity and a reduction of muscle sympathetic nerve activity, which increased in the evening.

“For now, all we know is that baroreflex control is the decisive factor, from the cardiovascular standpoint at least, to make evening training more beneficial than morning training, since it induces the other benefits analyzed. However, much remains to be done in this regard in order to obtain a better understanding of the mechanisms involved,” said Brito.

Baroreflex sensitivity regulates each heartbeat interval and controls autonomic activity throughout the organism.

“It’s a mechanism that involves sensitive fibers and deformations in the walls of arteries in specific places, such as the aortic arch and carotid body. When blood pressure falls, this region warns the brain region that controls the autonomic nervous system, which in turn signals the heart to beat faster and tells the arteries to contract more strongly. If blood pressure rises, it warns the heart to beat more slowly and tells the arteries to contract less. In other words, it modulates arterial pressure beat by beat,” Brito said. 

In previous studies, the EEFE-USP research group showed that evening aerobic training reduced blood pressure more effectively than morning training in hypertensive men (read more at agencia.fapesp.br/34194), and that the more effective response to evening training in terms of blood pressure control was accompanied by a greater reduction in systemic vascular resistance and systolic pressure variability (read more at agencia.fapesp.br/37432).  

“Replication of the results obtained in previous studies and in different groups of hypertensive patients, associated with the use of more precise techniques to evaluate the main outcomes, has strengthened our conclusion that aerobic exercise performed in the evening is more beneficial to the autonomic nervous system in patients with hypertension. This can be especially important for those with resistance to treatment with medication,” Brito ended.

Yoga focused on breathing, meditation, and relaxation is linked with symptom improvement in patients with heart failure.

This is according to research presented at Heart Failure 2024, a scientific congress of the European Society of Cardiology, with the study’s author, Dr. Ajit Singh of the Indian Council of Medical Research (ICMR), Manipal Academy of Higher Education, India, emphasizing that “patients who practiced yoga on top of taking their medications felt better, were able to do more, and had stronger hearts than those who only took drugs for their heart failure. The findings suggest that yoga can be a beneficial complementary therapy in patients with heart failure.”

Heart failure affects vast numbers of people – more than 64 million globally – and can have devastating impacts on quality of life, with patients feeling tired and breathless, and being unable to participate in their usual activities. While previous studies have shown the short-term benefits of yoga in patients with heart failure^.

This study enrolled patients aged 30 to 70 years with heart failure from the cardiology outpatient department of Kasturba Hospital in Manipal, India. All participants had undergone a cardiac procedure within the past six months to one year and were taking guideline-recommended heart failure medications. Patients with severe symptoms were excluded.

The study included 85 patients. The average age was 49 years and 70 (82%) were men. In a non-randomised fashion, 40 patients were assigned to the yoga group and 45 patients were allocated to the control group. All participants continued taking guideline-recommended heart failure medications throughout the study.

Experienced faculty in the hospital’s Department of Yoga demonstrated pranayama (yogic breathwork), meditation, and relaxation techniques to patients in the yoga group. Participants were supervised for one week and then advised to continue self-administered yoga at home once a week for 50 minutes. Patients spoke to an instructor after each home session to check progress.

At baseline, six months, and one year, the researchers assessed heart structure and function in the yoga and control groups using echocardiography. The measurements included the ability of the heart to pump blood (left ventricular ejection fraction), and assessment of right ventricular function. The researchers also examined blood pressure, heart rate, body weight, and body mass index. Symptom burden and the ability to do ordinary activities such as walking and climbing stairs were assessed using the New York Heart Association classification system.

Compared to the control group, the yoga group demonstrated significantly greater improvements in all measurements at six months and one year relative to baseline.

Dr. Singh said: “Patients who did yoga had healthier hearts and were more able to carry out ordinary activities such as walking and climbing stairs than those who only took medications. Patients with heart failure should speak to their doctor before starting yoga and should then receive training from an experienced instructor. Prescribed medications should be continued as before. Yoga may be unsuitable for heart failure patients with severe symptoms, who were excluded from our study.”