In a recent interview with ET, the actor talked about his training for the upcoming TCS New York City marathon and the toll it had on his body.
VIDEO: Mila Kunis and Ashton Kutcher share emotional video as they raise astonishing sum for Ukraine
"The biggest change physically has been the transfer of muscle mass from upper body to lower body. I've lost about 12 pounds," he said at the time.
He also shared that the biggest motivator was his wife and That 70's Show co-star, adding: "My wife [Mila] has been super supportive."
The actor also talked about what he'd learned during the months of rigorous training, saying that "surrounding myself with a support system makes hard things much easier.
"Setting a pace that you can sustain is not the same thing as working as hard as you can."
Ashton gushed about his wife being his biggest supporter
Ashton has been documenting more of his journey through his 16-part digital interview series, Our Future Selves, which includes segments of him training alongside several other celebrity guests.
He revealed that his biggest motivation was his family, including his two kids, daughter Wyatt, seven, and son Dimitri, five.
"My baseline 'why' comes down to leaving life better than what it was given to me. My daily motivator is my kids and family," he shared.
His family has been by his side since he revealed earlier in the year that he had been diagnosed with a rare autoimmune disease called vasculitis, which he opened up about on Running Wild with Bear Grylls: The Challenge.
The actor is training for his marathon with other stars in tow
"Like two years ago, I had this weird, super rare form of vasculitis, that knocked out my vision, it knocked out my hearing, it knocked out like all my equilibrium," he told Bear.
"It took me like a year to build it all back up."
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