Low-intensity exercise linked to reduced depression

New research finds strong association between physical activity and better mental health
New research finds a strong association between physical activity and better mental health.
New research has found a significant association between participating in low to moderate-intensity exercise and reduced rates of depression.
 
Researchers from Anglia Ruskin University (ARU) conducted an umbrella review of studies worldwide to examine the potential of physical activity as a mental health intervention.
 
The analysis, published in the journal Neuroscience and Biobehavioural Reviews, found that physical activity reduced the risk of depression by 23% and anxiety by 26%. A particularly strong association was found between low and moderate physical activity, including gardening, golf and walking, and reduced risk of depression. However, this was not strongly observed for high-intensity exercise.
 
Physical activity was also significantly associated with a reduced risk of severe mental health conditions, including a reduction in psychosis/schizophrenia by 27%.
 
The results were consistent in both men and women and across different age groups and across the world.
 
“Preventing mental health complications effectively has emerged as a major challenge and an area of paramount importance in the realm of public health. These conditions can be complex and necessitate a multi-pronged approach to treatment, which may encompass pharmacological interventions, psychotherapy, and lifestyle changes.
 
“These effects of physical activity intensity on depression highlight the need for precise exercise guidelines. Moderate exercise can improve mental health through biochemical reactions, whereas high-intensity exercise may worsen stress-related responses in some individuals.
 
“Acknowledging differences in people’s response to exercise is vital for effective mental health strategies, suggesting any activity recommendations should be tailored for the individual.
 
“The fact that even low to moderate levels of physical activity can be beneficial for mental health is particularly important, given that these levels of activity may be more achievable for people who can make smaller lifestyle changes without feeling they need to commit to a high-intensity exercise programme.”

Weight training improves symptoms of anxiety and depression in old people, study confirms

Brazilian researchers analyzed more than 200 articles on the subject and identified the types of training most indicated for these cases.

Weight training can help reduce body fat and increase muscle strength and mass in older people, contributing to functional autonomy and avoiding falls and injury. Furthermore, recent studies have shown that it can also benefit the mental health of older people, especially those who suffer from anxiety and depression.

These benefits were confirmed by a study reported in the journal Psychiatry Research. The study involved a systematic review and meta-analysis of more than 200 articles. The analysis was conducted by Paolo Cunha, a postdoctoral fellow with a scholarship from FAPESP at the Albert Einstein Jewish-Brazilian Institute of Education and Research (IIEPAE) in São Paulo, Brazil. 

“Resistance training has been shown to be one of the most effective non-pharmacological strategies for healthy aging. It promotes countless health benefits, including improvements to mental health,” Cunha said.

The findings of the study are highly promising, he continued. Besides improvements to symptoms of anxiety and depression in the general population, weight training appears to have a more significant effect on people with a confirmed diagnosis of anxiety or depression disorder.

“Epidemiological studies have shown that the decrease in muscle strength and mass that occurs naturally as we age may be associated with an increase in mental health problems, given the existence of various physiological mechanisms that bring about functional and structural changes and that are controlled by the brain,” Cunha said.

Another important mental health benefit, he added, is that when weight training is done in a group, it contributes to more social interaction among those involved.

Recommended exercises

The investigation also pointed to the best ways of structuring one’s training to improve mental health. “How the training is done appears to influence the results achieved. The information obtained so far suggests that older people should ideally do weight training exercises three times a week, with three sets of each exercise and sessions that are not too long – six exercises would seem to be sufficient. Do less, but do it well: a short set produces better results. This is meaningful information, as we lack guidelines with specific recommendations for resistance training that focuses on mental health parameters,” Cunha said.

While there are many possible ways to prescribe resistance training programs designed to improve the health, autonomy and quality of life for older people, most result directly or indirectly in improvements to symptoms of anxiety and depression, regardless of the intensity and volume of the exercises involved, according to Edilson Cyrino, last author of the article and principal investigator for the study. He is a professor at the State University of Londrina (UEL) and coordinates the Active Aging Longitudinal Study, a project begun in 2012 to analyze the impact of resistance training on parameters relating to the health of older women.

Another point observed by the researchers was that the use of training machines and free weights appears to be more beneficial for mental health than exercises that involve elastic bands or calisthenics (using the weight of the person’s body), for example. 

“We don’t have statistics comparing the two kinds of training, but the analysis showed that resistance training with weights and other gear is more effective in terms of improving the mental health of older people, largely because the intensity and volume of the exercises can be more precisely controlled,” Cunha explained.

Find out about the benefits of resistance exercise training in treatment of anxiety and depression.

A new study by researchers at University of Limerick in Ireland and at Iowa State University has demonstrated the impact resistance exercise training can have in the treatment of anxiety and depressive symptoms.
A new study by researchers at the University of Limerick in Ireland and at Iowa State University has demonstrated the impact resistance exercise training can have in the treatment of anxiety and depressive symptoms.

A new study by researchers at the University of Limerick in Ireland and at Iowa State University has demonstrated the impact resistance exercise training can have in the treatment of anxiety and depressive symptoms.

The new study provides evidence to support the benefits resistance exercise training can have on anxiety and depression and offers an examination of possible underlying mechanisms.

The research, published in the Trends in Molecular Medicine journal, was carried out by Professor Matthew P Herring at the University of Limerick and Professor Jacob D Meyer at Iowa State University.

The researchers said there was “exciting evidence” that resistance exercise training may be an accessible alternative therapy to improve anxiety and depression-like more established therapies while also improving other important aspects of health.

Dr Herring explained: “Anxiety and depressive symptoms and disorders are prevalent and debilitating public health burdens for which successful treatment is limited.

“The healthful benefits of resistance exercise training, or muscle-strengthening exercise involving exerting force against a load repeatedly to generate a training response, are well-established,” said Dr Herring, Associate Professor in the Physical Activity for Health Research Centre, Health Research Institute, and Department of Physical Education and Sport Sciences within the Faculty of Education and Health Sciences in UL.

“However, the potential impact of resistance exercise training in the treatment of anxiety and depressive symptoms and disorders remains relatively understudied. Moreover, the plausible psychobiological mechanisms that help us better understand how and why resistance exercise training may improve these mental health outcomes are poorly understood.”

The researchers argue that, while the available studies in this area are focused on relatively small sample sizes, there is sufficient evidence from previous and ongoing research at UL and the National Institute of Health-funded research with Dr Meyer and colleagues at Iowa State University to suggest that resistance exercise training does improve anxiety and depressive symptoms and disorders – though disorders themselves are scarcely studied.

“There is a critical need for confirmatory, definitive trials that adequately address limitations, including small sample sizes, but the limited evidence available to us provides initial support for the beneficial effects of resistance exercise training on these mental health outcomes, including increased insulin-like growth factor 1, cerebrovascular adaptations, and potential neural adaptations influenced by controlled breathing inherent to resistance exercise,” Dr Herring explained.

“We are tremendously excited to have what we expect to be a highly cited snapshot of the promising available literature that supports resistance exercise training in improving anxiety and depression. 

“Notwithstanding the limitations of the limited number of studies to date, there is exciting evidence, particularly from our previous and ongoing research of the available studies, that suggests that resistance exercise training may be an accessible alternative therapy to improve anxiety and depression.

“A more exciting aspect is that there is substantial promise in investigating the unknown mechanisms that may underlie these benefits to move us closer to maximizing benefits and to optimising the prescription of resistance exercise via precision medicine approaches,” Dr Herring added.

Professor Meyer, a co-author on the study, said: “The current research provides a foundation for testing if resistance training can be a key behavioural treatment approach for depression and anxiety.

“As resistance training likely works through both shared and distinct mechanisms to achieve its positive mood effects compared to aerobic exercise, it has the potential to be used in conjunction with aerobic exercise or as a standalone therapy for these debilitating conditions.

“Our research will use the platform established by current research as a springboard to comprehensively evaluate these potential benefits of resistance exercise in clinical populations while also identifying who would be the most likely to benefit from resistance exercise.”

Exercise is more effective than medicines in managing mental health

Exercise more effective than medicines to manage mental health
Exercise more effective than medicines to manage mental health


University of South Australia researchers are calling for exercise to be a mainstay approach for managing depression as a new study shows that physical activity is 1.5 times more effective than counselling or the leading medications.

Published in the British Journal of Sports Medicine, the review is the most comprehensive to date, encompassing 97 reviews, 1039 trials and 128,119 participants. It shows that physical activity is extremely beneficial for improving symptoms of depression, anxiety, and distress.

Specifically, the review showed that exercise interventions that were 12 weeks or shorter were most the effective at reducing mental health symptoms, highlighting the speed at which physical activity can make a change.

The largest benefits were seen among people with depression, pregnant and postpartum women, healthy individuals, and people diagnosed with HIV or kidney disease.

According to the World Health Organization, one in every eight people worldwide (970 million people) live with a mental disorderPoor mental health costs the world economy approximately $2.5 trillion each year, a cost projected to rise to $6 trillion by 2030. In Australia, an estimated one in five people (aged 16–85) have experienced a mental disorder in the past 12 months

Lead UniSA researcher, Dr Ben Singh, says physical activity must be prioritised to better manage the growing cases of mental health conditions.

“Physical activity is known to help improve mental health. Yet despite the evidence, it has not been widely adopted as a first-choice treatment,” Dr Singh says.

“Our review shows that physical activity interventions can significantly reduce symptoms of depression and anxiety in all clinical populations, with some groups showing even greater signs of improvement.

“Higher intensity exercise had greater improvements for depression and anxiety, while longer durations had smaller effects when compared to short and mid-duration bursts.

“We also found that all types of physical activity and exercise were beneficial, including aerobic exercise such as walking, resistance training, Pilates, and yoga.

“Importantly, the research shows that it doesn’t take much for exercise to make a positive change to your mental health.”

Senior researcher, UniSA’s Prof Carol Maher, says the study is the first to evaluate the effects of all types of physical activity on depression, anxiety, and psychological distress in all adult populations.

“Examining these studies as a whole is an effective way to for clinicians to easily understand the body of evidence that supports physical activity in managing mental health disorders.

“We hope this review will underscore the need for physical activity, including structured exercise interventions, as a mainstay approach for managing depression and anxiety.”

THIS COULD EXPLAIN A LOT – When chronic stress activates these neurons, behavioural problems like loss of pleasure, and depression result

When chronic stress activates these neurons, behavioral problems like loss of pleasure, depression result


Xin-Yun Lu, MD, PhD, (center) with Graduate Student Kirstyn Denney (left) and Postdoctoral Fellow Yuting Chen, PhD, both coauthors on the new paper CREDIT Michael Holahan, Augusta University

 It’s clear that chronic stress can impact our behavior, leading to problems like depression, reduced interest in things that previously brought us pleasure, even PTSD.

Now scientists have evidence that a group of neurons in a bow-shaped portion of the brain become hyperactive after chronic exposure to stress. When these POMC neurons become super active, these sort of behavioral problems result and when scientists reduce their activity, it reduces the behaviors, they report in the journal Molecular Psychiatry.

Scientists at the Medical College of Georgia at Augusta University looked in the hypothalamus, key to functions like releasing hormones and regulating hunger, thirst, mood, sex drive and sleep, at a population of neurons called the proopiomelanocortin, or POMC, neurons, in response to 10 days of chronic, unpredictable stress. Chronic unpredictable stress is widely used to study the impact of stress exposure in animal models, and in this case that included things like restraint, prolonged wet bedding in a tilted cage and social isolation.  

They found the stressors increased spontaneous firing of these POMC neurons in male and female mice, says corresponding author Xin-Yun Lu, MD, PhD, chair of the MCG Department of Neuroscience and Regenerative Medicine and Georgia Research Alliance Eminent Scholar in Translational Neuroscience.

When they directly activated the neurons, rather than letting stress increase their firing, it also resulted in the apparent inability to feel pleasure, called anhedonia, and behavioral despair, which is essentially depression. In humans, indicators of anhedonia might include no longer interacting with good friends and a loss of libido. In mice, their usual love for sugar water wains, and male mice, who normally like to sniff the urine of females when they are in heat, lose some of their interest as well.

Conversely when the MCG scientists inhibited the neurons’ firing, it reduced these types of stress-induced behavioral changes in both sexes.

The results indicate POMC neurons are “both necessary and sufficient” to increase susceptibility to stress, and their increased firing is a driver of resulting behavioral changes like depression. In fact, stress overtly decreased inhibitory inputs onto POMC neurons, Lu says.  

The POMC neurons are in the arcuate nucleus, or ARC, of the hypothalamus, a bow-shaped brain region already thought to be important to how chronic stress affects behavior.

Occupying the same region is another population of neurons, called AgRP neurons, which are important for resilience to chronic stress and depression, Lu and her team reported in Molecular Psychiatry in early 2021.  

In the face of chronic stress, Lu’s lab reported that AgRP activation goes down as behavioral changes like anhedonia occur, and that when they stimulated those neurons the behaviors diminished. Her team also wanted to know what chronic stress does to the POMC neurons.

AgRP neurons, better known for their role in us seeking food when we are hungry, are known to have a yin-yang relationship with POMC neurons: When AgRP activation goes up, for example, POMC activation goes down.

“If you stimulate AgRP neurons it can trigger immediate, robust feeding,” Lu says. Food deprivation also increases the firing of these neurons. It’s also known that when excited by hunger signals, AgRP neurons send direct messages to the POMC neurons to release the brake on feeding.

Their studies found that chronic stress disrupts the yin-yang balance between these two neuronal populations. Although AgRP’s projection to POMC neurons is clearly important for their firing activity, the intrinsic mechanism is probably the major mechanism underlying hyperactivity of POMC neurons by chronic stress, Lu says.

The intrinsic mechanism may include potassium channels in POMC neurons that are known to respond to a range of different signals, and when open, lead to potassium flowing out of the cell, which dampens neuronal excitation. While the potential role of these potassium channels in POMC neurons in response to stress needs study, the scientists suspect stress also affects the potassium channels and that opening those channels might be a possible targeted treatment to restrain the wildly firing POMC neurons.

Excessive activity of neurons is also known to produce seizures and there are anticonvulsants given to open potassium channels and decrease that excessive firing. There is even some early clinical evidence that these drugs might also be helpful in treating depression and anhedonia, and what the Lu lab is finding may help explain why.

Lu hasn’t looked yet, but she wants to further explore the role of these channels to better understand how stress affects them in POMC neurons and how best to target the channels if their findings continue to indicate they play a key role in exciting POMC neurons.  

Chronic stress affects all body systems, according to the American Psychological Association. Even muscles tense to keep our guard up against injury and pain. Stress can cause shortness of breath, particularly in those with preexisting respiratory problems like asthma. Longer term, it can increase the risk for hypertension, heart attack and stroke, even alter the good bacteria in our gut that helps us digest food.