[prairienights]

The horse/rider size thread reminded me that I wanted to ask this question.

I've always heard the general rule that a horse can carry a certain percentage of his own body weight, I believe 20%. But I read in one of my magazines (can't remember which, either Horse and Rider or Horse Illustrated, I'll have to find it again) that no horse, no matter what breed or size, should ever carry more than 250lbs including tack. I googled it, and found a few other sources that went by this rule. Once horses start getting larger, as in draft horses, they're supporting so much of their own weight on relatively small legs that it's wrong to think that they can carry massive loads.

But I've seen lots and lots of horses that have to be carrying at least that much, and they seem to be comfortable and balanced. Go to any western event, and you'll see large men with heavy tack on small horses. The horses seem fine, and often perform in those agile demanding disciplines.

Is there unseen damage being done? Is the 250lb rule a legit one?