Prince William sent royal fans’ pulses racing when he rolled up his sweater sleeve to get his first COVID-19 vaccine in a photo shared on Thursday, May 20. The Duke of Cambridge showed off he’s got a very fit and muscular right arm, and that has fans on Twitter gushing over the royal’s impressive biceps.

William rarely wears short sleeves, as he’s usually seen in suits or long sleeve sweaters. So when the @KensingtonRoyal Twitter account shared a photo of the Duke with his blue sweater sleeve rolled up all the way to his shoulder, the 38-year-old showed the world that he finds time to keep in amazing shape.

The caption of the photo read, “On Tuesday I received my first dose of the COVID-19 vaccine. To all those working on the vaccine rollout – thank you for everything you’ve done and continue to do.” But it wasn’t his commitment to public health that had fans buzzing.

“The Prince William vaccination photo has me feeling some things!” one Twitter user wrote, as another gushed, “Since everyone is thirsting over Prince William today, may I say that Catherine is one lucky girl?” One woman swooned over his photo, responding, “Pardon me Prince William, do you have a license to operate those guns?”

The vaccination took place at London’s Science Museum, where William received his jab by a member of the U.K.’s National Health Service staff. Both the Duke and Duchess Kate (née Middleton) have been strong supporters of the NHS’ efforts throughout the COVID-19 pandemic.

In the early months of the crisis, the couple regularly held Zoom calls with frontline health care workers. The pair even shared an Instagram video of their adorable children Prince George, 7, Princess Charlotte, 6, and Prince Louis, 3, clapping for National Health Service workers, which became a trend throughout Britain during the COVID-19 home lockdown to show appreciation for their heroic efforts during the pandemic.