Exercise and brain health: How are the two linked?

When you start getting into the rhythm, your brain gets an instant boost. Your heart rate gradually increases and more blood starts flowing to your muscles. The brain also receives more oxygen and nutrients. (Photo Wesley Tingey via Unsplash)

When we talk about fitness overall, exercise is the first thing that comes to our minds. Fitness coaches, doctors, and health professionals have all emphasised that exercise plays a crucial role in keeping us healthy irrespective of our age. But how does it affect our brain? Are there any immediate or long-term effects of exercise on our brain? Let’s find out!

When you start exercising, this is what happens to your brain on that day:

1.    First five minutes: Also known as the priming stage, when you start getting into the rhythm, your brain gets an instant boost. Your heart rate gradually increases, you start taking deeper breaths, and more blood starts flowing to your muscles. As more blood flows through the body, the brain also receives more oxygen and nutrients.

2.    First half an hour: Around 20 to 30 minutes into moderate or intense exercise, your brain starts producing feel-good hormones, also known as endorphins. It also releases endocannabinoids – chemicals that improve our mood, memory, and how we respond to stress. They also reinforce the motivation to exercise again. So, now you know why they say “You just need a kick-start”.

3.    One hour after exercise: High-intensity interval training (HIIT) workout produces brain-derived neurotrophic factor (BDNF) – an important chemical that helps with brain growth and functioning, including memory, cognition, concentration, and mood. Although BDNF production reduces as we grow older, studies have shown that it spikes after an HIIT session.

4.    Two to four hours after exercise: Some amazing neurotransmitters kick in after two to four hours of exercise. These magical chemicals are serotonin, dopamine, and norepinephrine – the ones that carry signals and information between neurons, basically the messengers! Serotonin is a mood elevator. It helps in managing the brain circuits that are crucially associated with sleep, mood, appetite, etc. It has a positive influence on cognition and the ability to think through difficult situations and controls impulsivity. Dopamine is the reward messenger that gives us the feeling of satisfaction while norepinephrine helps us in staying focused.

Long-term benefits of exercise:

If you start exercising regularly, your brain will get into the habit of generating good hormones and simultaneously reduce the effects of stress hormones. Here’s what happens in the long run when you start a good exercise regime:

1.    After 12 weeks of regular exercise: On regular exercise, the improved oxygen and nutrient supply helps in the growth of new neurons. The brain continues to release BDNF when you regularly do aerobic or HIIT workouts for three months. A positive impact on the size of the brain associated with memory also begins.

2.    More than three months of regular exercise: At this point, the impact of exercise becomes tangible. Your brain as well as your body starts to improve your overall metabolic health. A special hormone, insulin-like growth factor-1 (IGF-1), stabilizes your blood sugar levels and improves the body tissue’s sensitivity to insulin. Research says that poor metabolic health increases the risk of cognitive decline. The better your metabolic health, the better your neurological and brain function.

3.    Longer life and health span: Continuing to exercise protects us against age-related shrinkage of the brain, reduces the risk of cardiovascular disease, improves the overall quality of your life, physical fitness, your ability to memorise things and connect with people, especially during stressful situations, and boosts your confidence. Cumulatively, these give you a sense of being and feeling healthy, thus prolonging your health span and your life.

What to do?

The Centre for Disease Control and Prevention recommends at least 150 minutes of moderate-intensity aerobic activity or 75 minutes of vigorous-intensity aerobic activity per week, preferably spread throughout the week.
Strength training exercises using major muscle groups should be done on two or more days per week.

Consult your doctor or fitness coach/trainer before starting any new exercise programme, especially if you have any underlying health conditions.

The evidence from research supports the powerful link between exercise and brain health. By incorporating regular physical activity into your lifestyle, you can take a proactive step towards preserving and enhancing your cognitive function and brain health throughout your life. It will not only reduce the risk of depression and anxiety, but it will also improve your approach towards day-to-day matters and solving problems. So, begin today, exercise regularly, and give yourself the gift of good physical and mental health.