Mark Wahlberg Seems to Respond to David Beckham's Lawsuit, Shirtless Flex

Mark Wahlberg seems to be telegraphing a certain message with his latest thirst trap post -- which comes on the heels of David Beckham's lawsuit against his fitness company.

The actor threw up a video Wednesday on his IG page, and while it wasn't the first thing he's posted since David filed suit against Mark's F45 training brand ... it is the first one where he's shirtless and barking aggressively, interesting considering what's going on BTS.

The video's pretty simple ... it's Mark standing outside in the wee hours of the morning -- 4 AM, apparently -- which seems to be the start of whatever workout routine he's getting into.

Mark briefly talks to the camera, letting his audience they know what time it is ... and then he shouts out "Let's go!" before the clip cuts off. Like we said, it's not a direct response to David's legal action -- but does seem to give alpha dog vibes amid their beef in court.

Other videos Mark has posted in the past couple days mostly entail him plugging his Municipal brand -- so far, he hasn't explicitly addressed David filing suit against F45.

As we reported ... David alleged he got stiffed to the tune of $10 million after signing on with the company to be an ambassador for them -- and the way it all unfolded, according to him, was shady. Now, DB is trying to recoup what he claims is owed ... and straight up sued.

Mark isn't a defendant in the lawsuit, but F45 is undeniably tied to the guy ... MW has a 36% interest in F45 -- and he's the main face of the company ... popping up all over their socials.

While F45 has continued to post Mark-related clips on their own page -- Mark himself hasn't posted much about F45 in a little while. His focus these days seems to be Municipal.