The Flash's Grant Gustin has shown fans how much training is required to stay in shape as The Fastest Man Alive.

Gustin and celebrity trainer Ben Bruno shared a video on their respective Instagram accounts that showed The Flash actor performing various leg and arm workouts, including some that required him to be in a swimming pool. "[Grant] has been training hard for the upcoming season of The Flash," his trainer captioned the post. "This is some seriously impressive work. Let’s goooo!" The actor's training comes ahead of the start of filming on Season 9 of The Flash, which is set to commence in October 2022.

RELATED: The Greatest Gift the Flash Gave Fans Was the Original Barry Allen

Gustin first appeared in the Arrowverse as Barry Allen in the Arrow Season 2 episodes "The Scientist" and "Three Ghosts," with the latter setting up the character's transformation into the Scarlet Speedster. Although he was initially set to return for a third episode of Arrow that would have served as a backdoor pilot for The Flash, the positive reception to his first two appearances led to The CW instead choosing to develop a full pilot. The Flash premiered on The CW in 2014 to glowing reviews from critics and fans. The pilot also became the second-most watched premiere in the history of The CW. In addition to headlining The Flash, Gustin continued to make guest appearances on Arrow as well as other Arrowverse shows like Supergirl and DC's Legends of Tomorrow.

The Flash Will End After 9 Seasons

The Flash, which recently became the longest-running Arrowverse show in July 2022, is set to end with its upcoming ninth season. "It's been an incredible nearly 10 years of playing this character and getting to be a part of this show," Gustin said, shortly after The CW confirmed the DC superhero series was ending. "I'm very excited to do this one final time, finish on our terms, and I'm going to enjoy every minute of it as much as I can." Plot details for Season 9 remain scarce, but showrunner Eric Wallace has teased fans that the upcoming season will feel like a final season for Barry Allen and Team Flash.

RELATED: The Flash: A Full Circle Run for the Series Is Likely Impossible

The Arrowverse will also be ending next year with the conclusion of The Flash, the last remaining series set on the DC shared universe's main Earth. While Stargirl and Superman and Lois have crossed over with other Arrowverse series, they are only considered adjacent shows since they are set on separate Earths and not Earth-Prime (which is home to The Flash, Supergirl, Black Lightning and the Legends). However, Arrow and Superman and Lois star David Ramsey has hinted that the Arrowverse may live on in some form in future seasons of Superman and Lois.

The Flash Season 9 is expected to premiere on The CW in 2023.

Source: Instagram