I'm a few years older than you and I still get winded when I climb a long grade, will it ever end? Seriously, if you're sure you're not going to keel over from a heart attack, just keep pushing it. I find that when I push through the pain and keep gasping, eventually it takes more to wind me, and also to work up a sweat. I've ridden in mountains that seriously challenge you (altitude sickness isn't any fun) but when you can't go any further, you just dig a little deeper. I'm not recommending this behavior, it's just what I do, now let's hear what the smarter folks have to say.
