In this novel, aliens crash on earth in prehistoric times and use suspended animation to await technological development needed for repairs to their ship. They are discovered by an exploring youth and awaken a little before the ideal technology is available.
If the "exploring youth" is a young medical doctor hiking in the Rockies, you could be describing The Winds of Time, a 1956 novel by Chad Oliver. Quoting from P. Schuyler Miller's review in Astounding Science Fiction, October 1957 (available at the Internet Archive):
The book starts as an adventure. Wes Chase, vacationing M.D., is caught in a storm high in the Rockies and holes up in a convenient cave to wait it out. But there's a door in the back of the cave, and through the door comes an alien from the stars, who has been sleeping there for fifteen thousand years . . .
Then, on p. 44, the focus shifts to this starman—Arvon of Lortas—and the crew of the ship in which they have been searching the Universe for other men like themselves. The Lortans, alone among the human kind who teem among the worlds, have reached an ultimate technological world-civilization without first destroying themselves in atomic or bacterial war. But they have reached a dead end; to rise higher they need the cross-fertilization of ideas shared with another human race as advanced and stable as their own. And they can't find one.
The Lortan ship is wrecked on Earth, somewhere in Siberia, late in the Wisconsin glacial period when the first roving hunters are crossing to America. There's a nice and regrettably brief bit devoted to the nameless, pragmatically friendly folk among whom they fall, but five of the ship's company decide to put themselves into a fifteen thousand-year sleep in the hope that when they emerge, Man will be ready to build them a new star-ship. Instead, they awake in our time, with the atomic issue still unsettled and human technology still too crude for a space-drive.
In Anasazi, an alien spacecraft containing a species of parasites crashes in the prehistoric US southwest, in the region now known for the Anasazi, a.k.a. the Ancestral Pueblo culture. The aliens lack the means to fix their spacecraft or communicate offworld. They can't leave the area because they have to remain near some buried piece of alien tech. Being parasites, they survive by taking over the bodies of human children, switching bodies every few years because adult bodies are too difficult to control. In this fashion they survive hundreds of years while human society advances.
The main story picks up in the modern era. Mankind has finally developed technologies which the aliens could use to escape, and the aliens--still using the bodies of children--have been slowly building a device by scavenging radios and occasionally ordering electronic parts from out of town. Someone observes the children acting strangely, manages to connect the dots with some native american myths from the region, and figures out what is going on.
A big departure from your description is that I don't believe anyone is ever in suspended animation. The aliens are stuck in a particular place from paleolithic times to the modern age, but they're awake and living off of the local human population the entire time.