An athletic character working out is an excellent opportunity of Fanservice. It gives ample opportunity of sweaty bodies in constant motion, of labored breathing, of muscle flexing... This is a very common way to introduce stealth fanservice in works where it would otherwise be jarring to the audience, and it is especially popular in action movies or Shōnen anime, where it makes it easier for the guy to convince his girlfriend to join him. They don't have to be muscular, either (though they often are) - they just have to be working out. Nor do they have to be shirtless, but they certainly don't have to not be either. Female characters aren't excluded from this either, but it's more common for the character in question to be male. When they decide to work out, it can easily be justified as their way of training for a fight. They'll need their bodies into shape so they gets a better handle on the physicality of a fight. It also allows them to wield melee weapons easier, or it can be their way of honing his superhuman abilities... but lets face it, we're only really interested in the idea of a hot, sweaty, muscly guy or girl sculpting their abs in front of us. The guy/girl in question has to perform anything from push-ups and sit-ups, to pull-ups and weight-lifting. Being complete in the nude is certainly optional. Compare Macho Camp and Training Montage.
- Will Smith's character Neville starts out his day in I Am Legend with a big shirtless workout. So does his dog.
- Aerobicise was an early 1980s workout show on TV; it was also Poor Man's Porn. Lots of interesting angles on two to four hot chicks "demonstrating" workout techniques in a White Void Room.
- Ichigo Kurosaki from Bleach had a very brief scene in the anime where he made a couple of push-ups without a shirt. This was during the Soul Society arc, when he was training to get Bankai.
- Soundscape has Aloysius Thonnergan sculpting his abs in a gym. A bunch of girls took notice rather quickly. One even straddled him while taking pictures of his abs.
- CSI: NY came very close to it in 'My Name Is Mac Taylor', when Mac was doing his lap swim workout at the gym.
- James Vega does plenty of pull-ups in Mass Effect 3.
- Supernatural: In "The Third Man," Sam starts his day with some push-ups, some sit-ups, and some pull-ups, keeping himself in shape for hunting demons, monsters, and spirits. Though the focus is mainly on his back, upper chest, and biceps during the workout, we get some lingering shots of his abs above his low-cut jeans (yes, he worked out in the jeans) post workout.
- In The Avengers, Captain America is introduced with a loving shot of his body and ass while he was working out his frustrations on a series of punching bags.
- Ron Burgundy tries to invoke this on Anchorman by inviting Veronica into his office when he's "sculpting my guns". It doesn't work because his body betrays the fact that he doesn't work out that much, and because he keeps referring to his arms as "guns".
- Gentlemen Prefer Blondes has the incredibly beefy number "Ain't Anyone Here For Love?", which has Jane Russell wandering through a team's workout room.
- The video for Olivia Newton-John's song "Physical" started out and ended with multiple handsome, muscular men working out, including several Fanservice shots.
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