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Molly Kujawski has a family history of mental illness. In college she became depressed and took medication to fight the blues. At the same time, in an effort to counteract her genetics, she started working out regularly and eating better — and everything changed, including her mental health. “Once I got consistent with exercising and eating well, I didn’t need medication anymore,” she says.
In a word, she was happier.
Now 40 years old, the certified personal trainer and owner of ExcelFit With Molly in Fort Mill, South Carolina, is seeing the same transformation in her clients: Though vastly different in background and ages, they all struggled mentally and emotionally until they adopted a nutrition and exercise “prescription.”
“I’ve been training people since 2005 and have seen a direct correlation between consistent exercise and a boost in happiness,” Kujawski says. “I have clients who can attest to not needing medication or therapy now because of exercise. There’s a huge link there. It’s undeniable.”
Anecdotal evidence doesn’t always parallel science, but in this case it does, and more than 20 years of research has identified a connection between exercise and happiness. For example, a 2019 review of more than 20 papers published in the Journal of Happiness Studies found “a consistent positive relationship between physical activity and happiness … with as little as 10 [minutes of] physical activity per week.”
But the question remains, How and why does exercise make us happier? As with many things to do with mood, we turn to the brain for answers.
Quantifying happiness is a big challenge. Emotions and feelings are subjective, and depending on circumstance, your sentiment could change on a dime: One moment you’re happy, the next you’re angry or sad or unsure.
“We don’t have a good way to capture happiness that’s consistent from study to study,” says David Schary, Ph.D., associate professor of exercise science at Winthrop University in Rock Hill, South Carolina, who specializes in the psychological aspects of sports and physical activity. “But we do know that exercise has a substantial effect on depression — so much so that it’s [considered] to be just as effective as therapy or drugs — and can cause an increase in ‘subjective well-being,’ which is one metric used [in research] to measure happiness.”
Boosting your happiness quotient is entirely possible thanks to the neuroscientific concept of brain plasticity — the brain’s ability to change or rewire itself when exposed to new stimuli. And for someone who has been living a mostly sedentary life, regular exercise qualifies as a new stimulus, and an extremely powerful one at that.
Wendy Suzuki, Ph.D., professor of neural science and psychology at NYU and author of Healthy Brain, Happy Life (Dey Street Books, 2015), is renowned for her research on the brain-boosting effects of exercise, a “revelation” that landed her on national talk shows such as CBS This Morning and Dr. Oz. In 2017, Suzuki even did a TEDWomen Talk titled “The brain-changing benefits of exercise,” where she posited this query to the audience:
“What if I told you there was something you could do right now that would have an immediate, positive benefit [on] your brain, your mood and your focus? And what if I told you that same thing could actually last a long time and protect your brain from … depression, Alzheimer’s or dementia — would you do it? Yes! I am talking about … physical activity. Simply moving your body has immediate, protective benefits for your brain that can last the rest of your life.”
A bevy of research backs Suzuki’s claims, including a 2019 study published in the Balkan Medical Journal wherein subjects experienced reduced anxiety with an increase in their levels of oxytocin, a hormone/neurotransmitter brought about by physical activity.
“Research shows that sustained moderate- and high-intensity aerobic exercise activates the opioid and cannabinoid receptors … in the brain,” says Jason Karp, Ph.D., running coach and author of Work Out: The Revolutionary Method of Creating a Sound Body to Create a Sound Mind (2022, preorder on Amazon). “Opioids and cannabinoids are psychologically rewarding and can reduce anxiety and [promote] a general feeling of well-being.” This “runner’s high” makes you feel good about yourself and gives you confidence, according to Karp.
Though most studies to date have focused on aerobic exercise, resistance training has a similar effect. “I’ve seen both types of exercise work,” Schary says. “The biggest thing is being active and doing something to release those hormones. Exercise is that ‘magic pill,’ the one everyone is looking for to make them better in all aspects of life.”
Be proactive: Use these strategies to boost your bliss.
“Six days a week might sound overwhelming, but [the workouts] don’t have to be very long.” In fact, according to the American Psychological Association, just five minutes of physical activity per day is enough to boost your mood. And research published in JAMA Psychiatry found that running for 15 minutes (or walking for an hour) led to a reduced risk of depression.
Working out isn’t always fun, and even the best of us have days when we dread it. But if cultivating happiness is part of your overall objective, try your hardest to make exercise enjoyable. “If you hate running but love lifting weights, by all means be a weightlifter,” Schary says. Forcing yourself to do something you hate will counteract the positive effects of the exercise itself from a mental health standpoint.
Can’t find something you love? Try something other than a “traditional” gym workout, suggests Schary, such as hiking, biking, gardening, golf or home improvement.
In order to succeed, make sure you’re doing an activity because it’s what you want (internal) and not what someone else wants for you (external). “There’s nothing inherently wrong with wanting to beat your time in a 5K or lose some body fat, but if you’re doing an activity or pursuing a goal because your spouse wants you to, for example, that [impetus comes from a source outside yourself] and may not provide you happiness because it’s not internalized,” Schary says.
To divine if your motivation is internal or external, ask yourself these questions: (1) How much do I enjoy the activity? (2) How important is this activity to me?
“The more you enjoy it and the more important it is to you (and not someone else like a spouse, friend or society at large), the more internal the motivation,” Schary says.
Being part of a like-minded community can make exercise more pleasurable and thus easier to stick with long term. Kujawski, who trains clients both one-on-one and in small group classes, sees a significant difference in the enjoyment level of her group-training clients. “There’s a connection and an accountability between them,” Kujawski says. “We laugh and joke, the workouts are vibrant and energetic, and everyone sticks around and chats afterward. We even do social events once or twice a month.”
Collect those gym friends and get social: Organize a meet-up at a coffee shop or arrange a playdate for your kids. The stronger your fitness community, the more consistent — and happier — you stand to be.
“It’s hard to ignore the science behind mindfulness and improved happiness, but some people are turned off by [things like] meditation,” Schary says. “However, there’s a difference between sitting and meditating and simply being mindful as you go about your day; both are effective.”
For those in the anti-meditation camp, Schary recommends taking just one minute a day to sit quietly and breathe, no matter where you are or what you’re doing. “Once you get comfortable with a minute, bump it up to two minutes, then five or 10,” says Schary. Gradually lengthening the duration works much in the same way as incrementally increasing your running pace or the weight you lift in the gym. “You’re progressing your ability to be mindful,” Schary says. “This reduces stress and helps bring you satisfaction and, of course, happiness.”