While flying around with my loftwing, I frequently get into the situation where my loftwing starts stalling. I start moving slower and slower until it stops gliding and just flaps its wings as it begins to fall. This especially happens if I'm trying to go up; if I try to go down, the loftwing usually starts gliding again.
The only way out of this that I've seen is to press the A button to make it charge, but that is over quickly and I get right back to stalling. The help screen that appears when you press the 2 button doesn't say anything about what to do in this situation. Sometimes if I wildly wave around the Wii Remote, my loftwing gets going again, but I can't figure out what to do with that.
So how can I prevent my loftwing from stalling?