What the science says, what personal trainers see every day, and why moving your body is one of the most powerful things you can do for your mental health.
Most people know exercise is good for the body. But what it does for the mind is equally powerful, and the evidence has been building for decades. Anxiety and depression affect millions of Canadians, with one in five people experiencing a mental illness in their lifetime. While therapy and medication are important tools, exercise has emerged as a genuinely effective complement to both.
At 121 Personal Trainers, we see this firsthand. Clients come to us exhausted and overwhelmed, and something shifts over time. Not just physically, but in how they handle stress and carry themselves through the week.
What Happens in the Brain When You Exercise
Exercise triggers a cascade of neurochemical changes that directly affect mood. Your brain releases endorphins, serotonin, and dopamine, the neurotransmitters most closely linked to emotional regulation, motivation, and wellbeing. Low serotonin is a core feature of depression, which is why many antidepressants work by keeping more of it available. Exercise produces a natural increase.
There is also brain-derived neurotrophic factor (BDNF), which promotes the growth of new neurons, particularly in the hippocampus, the region of the brain responsible for memory and emotional regulation. Chronic stress shrinks the hippocampus over time. Regular exercise helps rebuild it.
Exercise and Anxiety
Anxiety is your body’s stress response working in overdrive. Exercise gives that stored tension a productive outlet, using stress hormones the way they were designed to be used. Your nervous system gets the message that the threat has passed, and your body begins to recover.
A 2019 meta-analysis published in the journal Depression and Anxiety reviewed over 100 studies and found that exercise produced significant reductions in anxiety symptoms, comparable in some cases to the effects of medication. Over time, regular exercisers also become better at tolerating physical sensations like a racing heart or shallow breathing, reducing the fear response that drives many anxiety disorders.
Exercise and Depression
A landmark study published in the Archives of Internal Medicine compared exercise to antidepressant medication in adults with major depressive disorder. After 16 weeks, both groups showed similar improvements, with the exercise group showing lower relapse rates at the 10-month follow-up. A 2023 analysis in the British Medical Journal concluded that exercise was as effective as, or more effective than, antidepressants for mild to moderate depression.
Kathy Merabian, Registered Clinical Counsellor at Creekside Counselling, sees this play out in her practice. “I always ask clients about movement. Exercise is not a replacement for therapy or medication, but the research is genuinely compelling. I have seen clients experience meaningful shifts in their mood and resilience when they add consistent physical activity to their routine. There is something about feeling stronger and more capable in your body that supports the emotional work we do in sessions.”
How Much Do You Actually Need?
You do not need to spend hours in the gym to see results. The Canadian Society for Exercise Physiology recommends 150 minutes of moderate aerobic activity per week, plus two strength sessions. That is roughly 30 minutes of brisk walking five days a week and two light lifting sessions.
For mood, even 10 to 20 minutes of movement can produce an immediate improvement. The deeper, longer-lasting changes come from consistency over weeks and months. Showing up three or four times a week at a moderate pace will outperform sporadic intense sessions every time.
Getting Started When You Are Already Struggling
If anxiety or depression is making the idea of exercise feel impossible, start smaller than you think you need to. A 10-minute walk counts. One set of squats counts. Momentum is built from small, repeated actions.
Reduce the number of decisions required. Plan when and where you will exercise before the day starts. Let go of the idea that a workout has to be perfect. Showing up on your worst day and doing half of what you planned is more valuable than skipping because you cannot do the full version.
A personal trainer helps remove the friction entirely. You have a scheduled time, someone expecting you, and a plan already made. At 121 Personal Trainers, every client gets a program built around their goals and wherever they are starting from today.
If you are experiencing persistent symptoms that are affecting your daily life, please reach out to a qualified mental health professional alongside your fitness routine.