And yet the logical consequence of a Thomistic theology is that prudent perfection of the body should be spiritually beneficial. If the object of Caritas is to perfect the form of the thing considered then its operation on the flesh is to perfect it. Now, for the spergs out there, I'm not advocating bodily perfection at the expense of the all the other facets of life a man must attend to, rather there needs to be a prudent balance, with the recognition that the neglect of the body is a sin. Doing a few reps for Jesus is a corrective.Spending too much time working out veers into the sin of vanity or pride. But away from the extreme, monks make beer for Jesus. Rather than "lifting for Jesus" and perfecting the body, pray during your workout. A quick search shows Protestants have no issue with it: How to Pray During Your Workouts.
I don't see how there would be anything wrong with "lifting" or "running" the rosary but I'm no theologian.