There is the odd night, here and there, where he dreams of nothing at all.
Some nights he dreams of the feel of a fist hitting a fragile body - the body he used to have before the needles and the vita rays, the body that he had trouble remembering was no longer his. He flinches, sometimes, when people throw a blow, because he remembers that once upon a time the fist would connect and there would be a crunch where now there was usually just a thud - if the fist is even fast enough to connect.
Those nights are ok. He usually wakes up fine. Rested.
Other nights he's back in the room with Erskine and Stark and the other scientists, in the metal tube, feeling the press of needles into his arms and the heat of rays through his body. That peculiar sense that everything was changing through the pain, the feeling of being too full and not full enough.
Those aren't too bad.
He dreams of bullets and guns and tanks and hydra weapons. Of explosions and comrades falling as they fight the good fight, but those dreams are just bad, he wakes from them, sweating, but he can roll over and fall asleep again because it was war and that was to be expected and really, when it got down to it, he'd been doing what he was meant to do then. It may not have been good but it had been right and he'd belonged with those men and women and he'd been doing his bit.
Then there are the nights when he dreams of the cold. Not the cold of the crash — that cold he can't remember. There is a wall of white in his memory, coming up at him through the windshield of the Valkyrie, and his therapists say that's to be expected, it's just too big a thing for him to contemplate, all that time in the ice, all those years lost. No. The cold he dreams of is the air rushing past him as he leans out of the train and watches Bucky fall. Sweat from the fight cooling on his skin, the strange feeling of wind in his hair and the cold, cold pit of dread in his stomach, the knowledge that this was real, this couldn't be fixed with a needle or a punch or some reassuring, meaningless words.
That was the cold that would have him waking, gasping for breath and springing from the bed to pace the room and sometimes, sometimes he would be lucky enough to calm the heart rate and get back to sleep because after all…
…they had their time. And even if he hadn't fallen, Bucky would still, now, be dead.
But there was a pattern on those nights when he woke up cold, and even if he could get back to sleep there was a chance he'd dream then of lips and a smile and a kiss that was supposed to be one of many but turned out just being…
Those are the nights he goes to the training room. Those are the nights he knows he's not going to get any more sleep and when he's honest with himself, he always tries to be honest with himself, he prefers those nights because for a few moments after he wakes up — when he can remember them that clearly, it almost feels as though they're still alive