"We have lived together for over 4 years, we have 2 handsome dogs, an fantastic business. and to top it off Tobi got down on one knee last week and asked me to marry him", Itsines wrote.
The trainer and "Sweat" co-founder posted on Instagram, "We have lived together for over four years, we have two lovely dogs, an incredible business....and to top it off..."
Alongside her photo, Kayla showed off a snap of her gorgeous diamond ring, which features a modern square stone and white gold band.
Itsines also has a sizable digital presence, with 9.4 million Instagram followers.
'I obviously said YES to spending the rest of my life with my very best friend.
Kayla also shared some of the awesome pictures with her partner on social media.
She created a series of successful fitness eBooks called Bikini Body Guides that include meal plans and a popular workout app called Sweat with Kayla. Their fitness empire propelled the couple's net worth to a cool $46 million previous year, and Itsines was named the #1 Fitness Influencer in the world by Forbes.