Zac Efron’s Workout Regimen for Iron Claw May Have Put Him at Risk for Stroke, According to Experts

By: ScreenGawk Staff | Published: Feb 03, 2024

Many have appreciated the ex-“High School Musical” star’s built physique — but now that Zac Efron has bulked up for his role in “Iron Claw,” he’s gone viral.

The problem? Health experts are flagging the workout routine he did to get him to this point, stating that it could put the average person at risk for a stroke or other medical emergencies.

Where Does the Risk Lie in This Routine?

Per findings reported in the Daily Mail, consistent heavy lifting over weeks or months of time can lead to deadly consequences.

Zac Efron in Iron Claw

Source: YouTube/KVUE

The outlet cited specialists from Set for Set, who confirmed — stating that “there is no practical reason to put [one’s] body under that much pressure and stress.”

Is Stress The Only Issue?

Both mental and physical stress often boil down to a shared common denominator that can intimately affect both areas of one’s workout experience: oxygen.

A male-presenting person powerlifts. Two men stand masked in the background.

Source: The Calgary Barbell/YouTube

The real culprit behind the concerns of death is a lack of oxygen over time, as those workouts typically have high oxygen demands to keep all of the muscles going quickly. This puts additional strain on the cardiovascular system, which can lead to a heart attack.

How Does Zac Efron Feel?

Zac Efron was 100% in “go mode” the entire time he filmed “Iron Claw,” going above and beyond in workouts and daily interactions.

Footage of Zac Efron in an ice bath was captured by a fan from his Instagram Story, and was put on YouTube for reference.

Source: Shirtless Guy Worldwide/YouTube

He interviewed with The Rake Magazine, confirming that he didn’t socialize while filming. “I was fully committed to the gym,” he said. “Wake up, ice bath, trying to find decent food, then training upwards of two hours per day.”

How Did Zac Efron Balance?

With such a busy schedule and an intense commitment to training, Zac Efron left many wondering how he balanced so well.

A scene from the movie (left) stands still next to Zac and a prominent film staffer in front of the Iron Claw photo backdrop

Source: Associated Press/YouTube

The truth? “[Training] was a singular focus for months,” the actor told Variety. “Your life goes out the window during prep. That necessity to be perfect became an obsession.”

It Worked Well for Zac Efron — Is There Any Real Risk to Trying This at Home?

While the temptation to mimic the celeb’s look can be strong, experts urge people to resist, per The Daily Mail.

A shot showing ex-bodybuilder Rich Piana is shown in a Then (left) and Now (right) montage, illustrating the risk of damage with excessive exercise, steroids, etc.

Source: Bodybuilding LegendsFacebook

The outlet cites its explanation for mental (as well as physical) health concerns. “Pushing both your body and mind to the extreme to achieve unattainable results can be damaging in the long run,” Set for Set experts told the outlet.


What Risks Do Folks Run?

Beyond the previously stated risks of heart attack or stroke, folks run a few additional risks — including cancer.

A person is clutching his chest that glows red, indicating a heart attack or blood pressure issues

Source: Canva

The Daily Mail confirms risks that include high blood pressure, weight gain, or weight fluctuation, among the previously stated risks. Beyond the actual physical risks, working out to this caliber consistently can lead to unnecessary mental stress.


How Much Is Too Much?

This begs the question — how much is too much, exactly? Zac Efron has confirmed with multiple sources that he worked out hours per day in preparation.

An example of an “Iron Claw” fight scene is shown (left) which Zac did multiple times per day in addition to everything else. A mini cast photo is shown on the right.

Source: FilmIsNow Movie Bloopers & Extras/YouTube

He has also said that in addition to this grueling routine, he would do volume training — eventually gaining 15 pounds of pure muscle. He would also wrestle in the actual scenes, which meant hours per day of movement.


How to Start (Healthily!)

The Daily Mail’s cited Set for Set experts confirmed that if people want to look like Zac Efron’s character over time, they have to start with bulking.

An example is shown of a caucasian male who has gone through the bulking process.

Source: BuffDudes/YouTube

Bulking is a casual term that bodybuilders use to define a period of time where they consume more calories than they need to fuel their workouts per Healthline. This works to build muscle quickly over time.


What Does Bulking Look Like?

Bulking can look different for everyone, and should generally be overseen by a personal dietitian or trainer to ensure one’s safety as one goes through the process.

A photo of two men about to engage in a fast food bulk is shown. It’s overlaid with the text 11,500 calories to grab attention, which is painted red

Source: MattDoesFitness/YouTube

Data from the University of Sydney confirms that male bodybuilders usually eat 3,800+ calories per day when bulking, while women average 3,200+ (via The Daily Mail).


Should (And Can) Everyone Bulk?

Set for Set experts confirmed with The Daily Mail that just because some can, doesn’t mean that they should.

Man standing in dark flexing muscles

Source: Canva

“Unless you’re an actor or a professional bodybuilder, there is no … reason to put your body under that much pressure and stress. … It can lead to catastrophic results that cannot always be easily reversed,” the experts said.


What Are You (And Zac) Gaining By Bulking?

While it may seem like you’re building clean muscle by bulking like Zac, this isn’t always the case. Data from the International Journal of Exercise Science confirms that most of the weight gain is actually fat.

Jeremy Ethier poses for the camera after a bulk gain of 20 pounds.

Source: JeremyEthier/YouTube

You might gain mental stress as well. When interviewed by Variety, Zac Efron noted that “having all that weight on, you don’t feel normal.”