Kali Muscle suffered a major health scare Saturday while doing what he does best -- working out at the gym, TMZ has learned.

The popular bodybuilder and YouTuber -- whose real name is Chuck Kirkendall -- passed out cold while exercising in a fitness center in California, his ex-wife, Dvyne Dirkendall, tells TMZ.

Kali was rushed to a hospital for treatment, but Dvyne tells us she doesn't know why he fell unconscious or the status of his condition. She noted Kali previously had a heart attack and needed a stent inserted into his heart to restore blood flow.

Kali has been posting on YouTube for more than 15 years and has nearly 4 million subscribers on the site, and is a fan fave on Instagram and TikTok. He's also a personal trainer and last year, began teaching social media tips and offering coaching sessions on financial stability.

He married his wife, Helena, in 2022.