Is it a good idea to sprint when it's very hot outside under the theory that it's best to exercise in a way that places intense but short-term stress on the body?
I think you're asking if the heat will add "good" stress.
I don't think so. There are specific, beneficial adaptations to sprinting that, as far as I know, are not improved by heat. I can't see that adapting to heat has any benefit unless you're specifically training to work-out or compete in a hot climate.
What do you define as "hot"? I'm in phoenix and I still keep my sprint regiment, we've hit about 107 lately. I don't see any draw backs. I just stay hydrated. Granted my whole sprinting/plyeometrics work out is only about 20 min. I run down to my park, do my sprints and jumping and run back. When its hot here it is definitely harder to do. If you can handle it, just keep hydrated. I plan to keep doing my sprints even past the 110/115 degrees.
Hot weather, appetite & nausea 2 Answers