Fat Horse, Bareback Problem, Summer Sore?

Well sometimes when horses gain weight, it affects their back and she may be a little sensitive! I'd suggest lounging her every day. Just light exercise, but if she seems like she can handle more than do more! If you do easy jogging, about a half hour a day should make progress! If your doing a faster trot then maybe a half hour or less. I wouldn't recommended lounging at the gallop because galloping is way easier for them then trotting! If your trying to get weight off her, go with either jog trotting or regular trotting at least a half hour a day. Try to get into a routine of it! It will help both you and her! Hope this helps! =D Good Luck! Also a handful of grain once a day wouldn't hurt but no more than that! And especially right now, try not to let her get more that a couple hours a day outside of the rich grass. If you have to leave her out, a grazing muzzle wouldn't hurt!