The delta time is the time since the last frame. Ofc, when you are debbuging, a frame takes verry long, as you are stepping through the code. Therefore the delta time can become huge.
But keep in mind, that the delta time can become bigger then expected, even without debuging.
Slow devices, f.e., can result in bigger delta times. So instead of "stopping" delta time, when debuging (i don't guess that thats even possible), you should limit it generally.
Also you might consider using an accumulator:
private float accumulator = 0;
public void render(float deltaTime) {
// fixed time step
// max frame time to avoid spiral of death (on slow devices)
float frameTime = Math.min(deltaTime, 0.25f);
accumulator += frameTime;
while (accumulator >= Constants.TIME_STEP) {
update(Constants.TIME_STEP);
accumulator -= Constants.TIME_STEP;
}
}
That means, that if delta is big, you take many little steps, instead of one big, and render the results then. This results in a more accuraate logic.
The limitation of the delta time is still needed, as on slow devices, a huge delta would result in many update-calls, which result in even bigger delta times and so on.