If you follow Physio on a Roll on Instagram you may have seen my post last week about exercise and mental health. If you missed it, I shared that the weekend marked 13 years since my first husband, tragically and unexpectedly passed away. Last week we would have also celebrated our 25th wedding anniversary and 29 years since we first met. All those milestones within a day or two of each other were tough. 13 years ago it was even harder and at times, even though I had magnificent help from my friends, I was overwhelmed by loss and grief. Exercise, particularly running, was and still is, my saviour. Why? Its powerful effects on improving my mood, clearing my head and organising my thoughts so that I just end up feeling better. Here is what the research says-

Mood boosting

• Several studies have found that exercise increases the amount of both serotonin and dopamine in the blood stream.  Serotonin and dopamine are both chemical messengers (or neurotransmitters). Serotonin promotes feelings of well being and happiness and improves sleep and appetite. Dopamine is critical in regulating motivation, memory, reward and attention.
• Exercise has potent effects on a range of other neuro-chemicals as well. Researchers suspect that much of the mood-boosting power of exercise is due to its effect on endorphins and other neuro-modulators involved in the endogenous opioid system. The opioid system is important in pain modulation, reward, response to stress and autonomic control (ie the flight or fight response). In both humans and animals, such natural opioids are increased in the blood after exercise.
• More recent research has uncovered an important role for endocannabinoids. This family of lipids — which activate the same receptors as the THC in marijuana does — are also increased in the blood after exercise.

Flight or fight response

• Exercise also increases the amount of norepinephrine (also known as noradrenaline) in the blood. Norepinephrine helps mobilise the brain for action. This means that it can deal with stress more efficiently and improve attentiveness.
• As exercise is a form of physical stress it gives the body practice at managing general stress levels. This makes us more resilient. How? The body produces many of the same physical reactions — heavy perspiration, increased heart rate — in response to exercise as it does when we feel threatened.  Research shows that while exercise initially spikes the stress response in the body, you then experience lower levels of the stress hormones cortisol and epinephrine (adrenaline) after exercise. This "priming" to stress protects the body from the negative physiological effects of future stressors.
• Regular workouts may then help people prone to anxiety become less likely to panic when they experience those fight-or-flight sensations. Exercise in this sense becomes an exposure treatment, helping  people learn to associate the symptoms with safety instead of danger.

Buffering the brain

• Another theory suggests that exercise helps by normalising sleep, which is known to have protective effects on the brain. Recent findings suggest that sleep plays a housekeeping role in your brain, removing toxins in that build up while you are awake. (A topic for a future blog!).
• Exercise may boost a depressed person's outlook by helping him return to meaningful activity and providing a sense of accomplishment.

It's likely that multiple factors are at play in the effect of exercise on mental health. Exercise has such broad effects that there appears to be multiple mechanisms at multiple levels affecting the brain. And there are still large gaps in our understanding of the exact mechanisms by which exercise changes the brain. This is largely because it is difficult to directly measure the effects in humans and as such much of our knowledge is derived from animal studies. Questions also remain about which type of exercise is most helpful. Most studies have focused on aerobic exercise, of moderate intensity. Some research suggests weight training and mind-body exercises like yoga, which have been practiced for centuries, might also be effective but have yet to be thoroughly studied. Researchers similarly don't yet have a handle on how much exercise is necessary for mental health benefits or even whether exercise works best in conjunction with other therapies. Despite this, there is little doubt about its benefits.

Motivation

But, of all the questions that remain to be answered, perhaps the most perplexing is this: If exercise makes us feel so good, why is it so difficult for some of us to do it? Sometimes people skip their workout at the very time it has the greatest payoff.

• Starting out too hard in a new exercise program may be one of the reasons people dislike physical activity. When people exercise above their respiratory threshold ie, at a level where it gets hard to talk, they postpone exercise's immediate mood boost by about 30 minutes. For someone new to exercise, that delayed gratification could turn them off the exercise bike or treadmill for good.

Instead, start slowly. Start small. Also start with a moderate exercise plan. And set a routine. Even if you are too busy. 

• Similarly we are often encouraged to exercise to lose weight, lower our blood pressure or cholesterol count. Unfortunately, it takes months before any physical results of your hard work are apparent. So we give up waiting for those physical effects to appear.

Instead do what enjoy and monitor your progress. This will help you to see the connection between how moving makes you feel better.

The takeaway

So if you are feeling stressed, overwhelmed or in need of a boost, make the time, even when you think you are too busy for exercise. That might be a walk to a park or some simple stretches (maybe with your foam roller 😃), yoga or heading off on a run like me. Now I certainly don’t run as far (or as fast) as I did when I was younger. And I do have days when it is difficult to drag myself out of bed and lace up my joggers. But I know I will reap the benefits afterwards. Your brain (and your body) will also thank you. #exerciseismedicine.