And the fact that many trendy fitness brands don't make clothing above a certain size while larger women are often fat-shamed and told to "just work out more is "a vicious cycle that is perpetuated by many industries.

Overweight and obese people are highly discriminated against by personal trainers, doctors, nutritionists, therapists, etc., Dr. Christel said. Then, add to that the difficulty of finding workout clothing that makes you feel good about yourself, which, Dr. Christel adds, "greatly impacts women's motivation to be active."

"Despite these many social barriers, plus-size women are active," Dr. Christel said, "and they deserve fashionable, affordable, easily accessible athletic clothing."