Dean watches Cas work out on one of those ab-roller things with rapture.
Ever since Cas became human he has taken the "body is a temple" bull shit seriously. Dean knows he shouldn't complain, but he can't help the groans escaping when Sam and Cas are awake at the ass crack of dawn yoga-ing and making Dean drive them to the gym. Dean knows he shouldn't complain because Sam always buys him a cinnamon bun and a large coffee at the small cafe in the health center while they work out or take a class. Dean knows he shouldn't complain because Cas comes back to him, smiling, sweaty, flushed, and peaked with energy. He orders a smoothie and they wait for Sam to be done doing some turbo ab and butt buster course with a very fit brunette instructor, and Dean just listens to Cas marvel at the strength of the human body and the dedication of the mind. Dean knows he can't complain about the yoga mats left on the floor of the bunker, the green and orange and red and yellow produce on the fridge, the way Cas methodically chops onions, garlic, bell peppers, and tomatoes. Dean can't complain about the way he feels after eating a meal Cas made, delicious and flavorful, and he definitely cannot complain about the way Cas looks.
Cas, stretched taunt across the floor, holding his body in straight plank, his shirt riding up to show his lower stomach and his butt prompt and center. In his black yoga pants, Cas' ass looks fucking amazing and as he rolls forward the tendons around his elbows plump, the definition in his forearms wave and then as he rolls back, his shoulders tighten, his ass tightens, his face tightens in concentration and it drives Dean up the wall and leaves him filled with heavy breaths.
Which is why Dean decides to start doing yoga with Cas. He thinks it'll be best to start out easy, except that yoga is not that easy. But he gets to watch Cas bend and pose, and he gets to listen to his voice for an hour, which isn't that bad. Sam scoffs when he first hears Dean tell them he wants to join in, but when he sees Dean making an effort to stretch, breath, and balance, he relaxes off the smart remarks.
Everyday Cas does yoga, has a cup of tea with honey, and cooks a huge breakfast. Dean slowly becomes accustomed to this routine, waking up early, getting into his work out clothes, and joining Cas in the dark early hours on their mats, quietly meditating and stretching. Dean learns to clear his mind, to feel his breath, and to answer his body when it calls. He learns he can make his body do anything when he gives it what it needs and focuses on the training. It's different than hunting, because there's no drive, rush, or forces of nature working against him which he must push, push, push, until the calm.
Then Sam gets up and has his coffee and toast and an apple, or mango, or a banana, whatever Cas cut up for them, and they drive to the gym. Sam quickly rushes off to class after a quick good bye, and Dean and Cas are left to themselves. Sometimes they walk around the track, silently, or sharing weird tid-bits of chatter. Sometimes, Cas joins the tai chi class outside, which Dean finds pointless and boring.
One day, when Cas is doing his weird stances outside, Dean wanders around the center, which is huge, and intimidating, with everyone in their tight tank tops and shorts, tan, toned, and focused. Dean finds himself in the lowest level, were there is a huge open space. One wall is covered in floor to ceiling mirrors, another wall is lined with free weights, and in a row down the middle giant bags filled with sand hang from two inch thick chains. In one corner a headless torso sits atop a stand, in another, a head sized tear drop shaped leather bag hangs from a pole. There are a few small lockers near him with wooden benches, where a dude in a loose t-shirt, baggy gym shorts and a head full of dreads wrapped in a tie-dye scarf sits wrapping his hands in white fabric. The dude looks up, eyes Dean, and says, "Hey. I'm Ted. Are you here for the class?"
Dean goes, "Uh, what class?"
The dude smiles, "The boxing class," and throws a few rolled up strips of the tough fabric at Dean. Dean catches them, and he shows Dean how to wrap his knuckles, with the loop sewed onto one end of the strip over his thumb, then the fabric wrapped around his thumb twice and interlaced through each finger, tight across the knuckles and the palm, then velcro-ed around the wrist. He slips a pair of boxing gloves over Dean's hands and ties them tight.
"Let's start on the bag," he says, and leads Dean to one of the heavy bags hanging from the ceiling. Ted positions Dean in an athletic stance, legs apart, one foot back for balance. "Keep your hands near your face, and extend your arm out straight," Ted says, calm and cool. Dean does and the bag swings a few inches, "Ok, that was good, now pivot your back foot, and remember that your power comes from your hips." Ted shows Dean a quick left jab, the back swings five inches and comes back around. "I'm going to hold the bag right here, and when I say left, you jab with the left, when I say right, you jab with the right." Ted positions himself behind the bag, opposite of Dean, and holds his body weight against it. "Left, right, left, left," Ted repeats. Dean finds the rhythm, feeling the power from his hips as he punches the bag straight and brings his glove back to his face. "Good, that was really good, have you trained before?" Ted asks.
Dean says, a little breathy, "Just a natural born fighter."