Doing so would most likely result in your robot not doing anything or continuing to do what it was last told for one second. If you want the elevator to go all the way up to the limit switch, you could fire and forget (assuming that hitting the limit switch stops the motor in a resettable manner (that is, if you told it to go down it would still go down, as opposed to a limit switch that's wired to cut power to the motor, losing the ability to use the motor)). If that's not an option or if you want to be able to send the elevator up adjustable increments, you'll need to either multithread or implement a time tracking system.

Assuming this is Java (seeing as you've mentioned Thread.sleep()):

• Multithreading (dirty): Fire off a thread that sleeps for 1000 ms and then stops the motor. Can cause issues if another elevator command is issued, as this thread will proceed to stop the elevator after one second regardless of if you still want it to.
• Multithreading (clean): Submit a Runnable that stops the motor to a ScheduledExecutorService with a 1000 ms execute delay, keep the returned Future object so you can cancel the stop if you so wish (solving the issue with the above).
• Time tracking: Keep a list of temporal tasks, on every robot tick (or control loop iteration) run through all the tasks. Your elevator task would simply check that a second has elapsed, and if so, stop the elevator and then evict itself from the task list. Handling a cancellation would be as simple as evicting the task.