Weights for Wellbeing

STRENGTH TRAINING IS THE SUREST WAY TO BUILD YOUR BEST BODY, BUT A GROWING COLLECTION OF RESEARCH SUGGESTS IT’S ALSO ONE OF THE MOST EFFECTIVE METHODS FOR MAINTAINING SOUND MENTAL HEALTH

How resistance training can bolster your mind as well as your body

Like many others, Russ Polson struggled during the depths of lockdown. e 31-year-old was used to being active, heading to the gym most days and playing in an American football team. But with everything shuttered, and no escape from the grinding reality of the pandemic, his mental health took a dive.While other people started pounding the pavements, Polson began to lift weights and do squats at home. And when restrictions started to ease, he headed back to his local gym.

“e di erence in my mood when I could get into the gym for an hour was immense,” he says. “I was happier, had more patience with my small child, and began to look more positively towards the end of the pandemic and getting back to normal.”

Not only did the gym give him a change of scenery, but working on his strength also honed his focus and helped him feel motivated: “Even though it seemed like I couldn’t go about my life as normal, I could push myself and see improvements. I like the feeling after lifting: the blood owing and all the good chemicals in my brain.”

e link between exercise and good mental health has long been established.

However, you don’t have to run a 10k to experience a rush of endorphins; training your muscles and pushing yourself to become stronger can deliver a similar high.

MUSCLE UP

Until recently, much of the research into exercise and mental health has centred on the benefits of cardio activities like running and cycling – and less so on the impact of strength training. Last year, however, a study of 150,000 participants found a connection between lower muscle strength and cardiorespiratory fitness, and a greater risk of mental health problems.1 In fact, those classified as having low combined fitness and muscle strength had 98 per cent higher odds of experiencing depression. Other factors may be at play, including that people with better mental health may be more likely to stay physically active. Yet evidence is gradually emerging of a link between strength training and psychological wellbeing. In 2018, Dr Brett R. Gordon, now a postdoctoral scholar at the Penn State College of Medicine with the Oncology, Nutrition, and Exercise group, analysed the results of 33 experiments on weight training and depression with colleagues at the University of Limerick. He discovered strength training was linked to improvements in depressive symptoms, such as low mood, a loss of interest in activities and feelings of worthlessness. And although lifting weights isn’t a cure, the exercise appeared to reduce the symptoms of depression – no matter the number of weekly workouts. “There are several potential biological and psychological factors suggested to influence or help explain how and why strength training may improve mental health,” he explains. “Psychological mechanisms include social interaction during exercise, feelings of mastery following progressive improvements in strength made through training, or expectations of improved mental health following strength training.”

DISTRACTION AND EMPOWERMENT

Strength training involves focus and concentration to do each movement or repetition while avoiding injury. While running allows your mind to wander, training specific muscles can distract from ruminating or focusing on worrisome, negative thoughts. That may explain why resistance training has been shown to help people manage symptoms of anxiety. In one study, for example, scientists from the University of Georgia took a group of women with generalised anxiety disorder and assigned them to one of three groups: resistance training, aerobic exercise, and a control group. Both

types of exercise led to a signi cant drop in symptoms of worry, with subjects in the resistance training group seeing the best results. e physical impact of resistance training on the body can have a positive e ect on your con dence, too. Lifting more, or managing more reps, is a clear sign of physical progress – and that invariably feels good. “After exercise, the individual will likely feel the cognitive bene ts of a sense of achievement for engaging in a training session,” explains Dr Amy Izycky, a clinical psychologist specialising in sport and neuropsychology and author of

Skewed to the Right: Sport, Mental Health and Vulnerability.

“e likely physical impact of resistance training on the body could also indirectly improve someone’s self-con dence and support development of more positive relationships to one’s body.”

CHEMICAL MESSENGERS

Our chemical make-up also plays a key role in why exercise is so good for our brains. When you physically exert yourself, you experience a release of endorphins: a type of neurotransmitter or chemical messenger that can help relieve pain and stress. Physical activity also stimulates the release of dopamine, norepinephrine and serotonin: brain chemicals that play an important part in regulating your mood. “With regard to the impact of exercise and resistance training, we are interested in the impact of endorphins and other neurotransmitters including serotonin, dopamine and norepinephrine,” explains Dr Izycky. “Endorphins have become popularised as one of the ‘happy hormones’ but they are actually an inhibitory neurotransmitter that can inhibit pain signals.” Regular exercise also helps balance your body’s level of stress hormones, such as cortisol and adrenaline. ese hormones act as an alarm system in our bodies and play a crucial role in our ‘ ght-or- ight’ response, alerting us to avoid potential threats. is biological trigger helps keep us safe from danger, but it can easily go into overdrive when we are faced with the stresses of modern life. Luckily, research suggests strength exercise can play a role in relieving us of these hormones when necessary.

In a 2007 paper, University of Zurich researcher Ulrike Rimmele and her team assessed the impact of physical stressors on trained men compared to untrained men. “Cortisol was found to be signi cantly lower in trained men when they were exposed to stressors,” says Dr Izycky. “ey concluded that physical activity may provide a protective e ect against stress-related disorders.” To better understand the link between exercise and mood, scientists have also begun to explore another class of brain chemicals: endocannabinoids. Your endocannabinoid system is made up of the body’s own cannabis-like substances and their receptors. Although we don’t know exactly how the system works or all of its potential functions, it has been linked to the immune system, mood, memory and learning. Areas of the brain that regulate the stress response, including the amygdala and prefrontal cortex, are rich in receptors for endocannabinoids. In 2019, researchers at Iowa State University and the University of Wisconsin-Madison found the activation of these receptors appeared to strengthen connections in the brain and may in uence pain and depression. Speci cally, they found a signi cant boost in the number of endocannabinoids and improvements in mood following prescribed moderate-intensity exercise.

FLEXIBLE BRAINS

When you do resistance training, your muscles, heart and lungs become stronger. However, research suggests your brain also has the capacity to change in response to internal and external in uences, in a phenomenon called neuroplasticity.

Neuroplasticity refers to the physiological changes in the brain that happen as a result of your environment. It was once believed that the creation of new neurons – the building blocks of the brain and nervous system

– all but stopped after birth. Now, we know that the brain can change, adapt and grow throughout our lives and in some cases, even create new neurons. Scientists have suggested exercise can

“Lifting more is a clear sign of physical progress – and that invariably feels good”

help boost neuroplasticity, which has the potential to prevent conditions such as Alzheimer’s disease.

But why?

When we exercise, hormones and other chemicals cross from the blood into the brain, triggering changes in its structure and function. New brain cells are formed, new blood vessels are established and stronger connections develop between cells, providing the brain with oxygen and other nutrients. Resistance training has also been shown to increase the size of certain regions of the brain – a change that has been linked to improvement in mental function.

Recently, scientists have begun to explore whether ‘corrective neuroplasticity’ could be a new treatment avenue for depression and anxiety. However, we’ve only just begun to delve into this complex theory and more research is needed.

“Human and animal studies have shown that exercise can elicit changes in many of the same brain regions a ected by those with depression and anxiety,” explains Dr Gordon. “But research in this area is limited due to several factors, including the diverse symptom pro les of anxiety and depression, and the di culty of measuring changes in the brain.”

With research ongoing, we may well know more about how neuroplasticity can impact mental health in the future. But what we know for sure is that strength and resistance exercises are good for both the body and the mind. Although physical activity isn’t a cure, it can help us manage conditions like depression and anxiety – and have a lasting, positive e ect on our brains.