Ryan Lochte's Wife, Kayla, Files For Divorce

1:25 PM PT -- Ryan Lochte just opened up on the divorce ... writing on his Instagram page he believes the split is "the right step toward peace and well-being for us both."

"I remain committed to healing, growth, and co-parenting with care and respect as we move forward separately," he said. "Thank you to our family and friends for your continued support -- it truly means a lot as we begin this new chapter."

Ryan Lochte and his wife have split ... TMZ Sports has confirmed Kayla Lochte filed for divorce from the Olympic great earlier this year.

Court records we obtained show Kayla formally submitted the docs to a Florida courthouse on March 26 ... and in an emotional Instagram post Wednesday, she called the decision to move on from Ryan "one of the most painful, revealing, and challenging seasons of my life."

"Sometimes we face trials we didn't choose or see coming, and in those moments, we're forced to make the hardest decisions to protect our peace, our children, and our future," she wrote.

"I've come to understand that staying isn't always the most loving decision someone can make. For me, leaving was an act of love -- for those around me and for myself."

She asked her 338,000 IG followers for "prayers and continued support" ... stressing they "mean the world to me right now."

Ryan and Kayla -- a former Playboy Playmate -- began dating in 2016 ... the same year he made both positive and negative headlines at the Rio Olympics.

The two tied the knot in 2018. They have three kids together -- one son and two daughters.