Zac Efron says stem cell therapy helped him heal from The Iron Claw injuries

Zac Efron says he has pursued stem cell therapy amid his recovery from his physically taxing role as pro wrestling icon Kevin Von Erich in A-24's The Iron Claw.

'I fully commit to my roles, which I love, but it takes a toll - my back was messed up after The Iron Claw, even after months of PT,' said Efron, 36, of injuries he suffered making the 2023 movie.

The San Luis Obispo, California-born entertainer said that 'curious about stem cell therapy,' he 'reached out to' Dr. Adeel Khan at the Canada-based clinic Eterna Health.

Khan 'answered all my questions and made me feel confident' in the treatment, the Hollywood leading man said.

The High School Musical alum, who suffered a chest injury in Ibiza last month , said that half a year removed from the regimen, he feels better physically.

'Now, six months post-treatment, I'm back in the gym and already seeing improvements ,' the Baywatch star said.

The Gold actor wrapped up in saying, 'Excited to explore the latest longevity technologies through the Eterna Membership Program - I'll keep you updated on my progress!'

According to a synopsis from The Mayo Clinic , stem cells are 'special type of cells that have two important properties,' as they 'are able to make more cells like themselves' and 'can become other cells that do different things in a process known as differentiation.'

Found in all tissues in the body, the stem cells are critical 'for the maintenance of tissue as well as for repair after injury.'

The clinic noted that there has been a long-running controversy about stem cell therapy, as 'embryonic stem cells are taken from early-stage embryos' which are 'a group of cells that forms when eggs are fertilized with sperm at an in vitro fertilization clinic.'

With the extraction of stem cells from human embryos, the ethics surrounding the practice has past been challenged by critics, according to the clinic.

The National Institutes of Health in 2009 developed a set of guidelines for professionals to apply when researching human stem cells .

The guidelines set criteria for stem cells with a definition of embryonic stem cells; how they can be used amid studies; and recommendations for donating them, the clinic said.

'The guidelines state that embryonic stem cells from embryos created by in vitro fertilization can be used only when the embryo is no longer needed,' the clinic said.

Efron told USA Today last year that he found himself taken aback by the physical demands as he had to train as a pro wrestler for the role of Von Erich .

'You think you're getting the hang of it, and you speed up a few times and your confidence gets built up,' Efron said. 'Then you slam into one of those things just an inch too high and your rib is like gone. You can't breathe for a couple days.

'I don't know how these guys do it, man ... it's shocking that first time you do it. You're like, "This is not as easy as it looks on TV."'

Efron spoke with Variety that month about the regimen he underwent to add 15 pounds of muscle for the part.