Are my dendrobiums supposed to be growing so tall?

[ThePizzaMonster]

I've had these dendrobiums for about a year now and recently they started growing what I thought were spikes but in reality it was just more leaves. In the space of a couple of weeks they grew to maybe double the size and new shoots grew even taller than the old shoots.

Is it in response to more light or what is going on? They haven't bloomed so far.

I realize some leaves are sunburnt and I already moved them to a shadier spot.