Lionel Messi caught fans off guard recently when footage of him lifting weights during a Paris Saint-Germain training session went viral.

While the seven-time Ballon d'Or winner is renowned for being a wizard with the ball at his feet, it's rare that his legions of admirers get an insight into his work in the gym.

The Argentine superstar - who stands around five foot seven inches tall - was famously diagnosed with growth hormone deficiency when he was 11 years old, but has defied the idea that it is necessary to be blessed with power in order to be an elite athlete throughout his career.

Per The Athletic, Messi's growth hormone issue was addressed via injections of Human Growth Hormone into his legs on a daily basis.

That treatment, believed to have cost around $900 each month, was funded by Barcelona as part of the deal that saw him move to Camp Nou at the age of 13.

Given that he went on to become the greatest player in the club's history, it turned out to be some of the best money La Blaugrana has ever spent!

Messi wheels away celebrating in 2012.

BARCELONA, SPAIN - DECEMBER 16: Lionel Messi of Barcelona celebrates scoring his sides third goal during the la Liga match between FC Barcelona and Club Atletico de Madrid at the Camp Nou stadium on December 16, 2012 in Barcelona, Spain. (Photo by Jasper Juinen/Getty Images)

The pre-teen Messi was often responsible for administering these injections himself, but the sacrifice was worth it. Eventually growing to his current height, he has ruled the game for much of the last two decades, crowning his iconic career by lifting the World Cup for his beloved Argentina last month.

For all the countless documentaries and tribute packages that have been made on Messi down the years, though, his workout routine has always remained pretty private.

Make no mistake, Messi is a supremely well-conditioned athlete who clearly puts in a lot of time and effort in training.

Lionel Messi in action for PSG

Soccer Football - Champions League - Group H - Juventus v Paris St Germain - Allianz Stadium, Turin, Italy - November 2, 2022 Paris St Germain's Lionel Messi before the match REUTERS/Massimo Pinca

However, despite his long and storied career, the sight of the 35-year-old lifting weights isn't something his fans are used to.

Therefore, when PSG released a video of their squad working out in the club gym recently, a simple one-second clip of Messi lifting a barbell went viral, together with the caption: "I swear that's the first time I've seen him lift weights."

You can check out the clip - as well as the full video - below.

Video: Rare clip of Messi lifting weights in the gym goes viral

You know you're ridiculously famous when you can't even do a couple of reps in the gym without sending social media into meltdown!

To his devoted fanbase, Messi lifting some weights was a big deal and we've included the best of their reaction below.

Messi lifting tweet

Messi lifting tweet

Messi lifting tweet

Messi lifting tweet

Messi lifting tweet

Messi lifting tweet

Messi lifting tweet

Messi lifting tweet

Messi lifting tweet

Messi lifting tweet