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.”