Goin on the mule ride in may/2000 am 65 and 35 years old. Am wondering how much pain we will be in after riding the mule for 6 hours each way?
Got any ideas on recouperating taking a535/hottubs in the area etc?

What mule ride are you talking about? Grand Canyon? If you don't ride often, you will be in pain. Especially if you are not in good physical condition. Massage + hot tub + Advil. Won't help the sitting down parts though.

Somewhere near your home there is surely some type of equestrian establishment that would let you ride a gentle horse for an hour at a safe pace, for a fee of course. If the ride of an hour gives good results, then try riding again for 2 full hours a few days later. There is considerable difference in how the body responds when you double the time. That way you can guage how your body might handle a 6 hour trip.
At 65, I would not have tried riding for that long, even though I had a horse when I lived on a farm as a young teenager.
Conventional wisdom says you will be sore and find walking difficult for several days after your trip unless you have done something to prepare. We do not usually sit that way, and there is not much you can do around the house that will prepare you to sit for hours with your legs in a straddle position. Hopefully those mules are gentle enough that you do not have to grip with your knees to stay in the saddle. If you do, bear in mind that if you have not ridden frequently, you simply don't have the muscles and the toughness to withstand the prolonged riding posture and effort. I am hoping some experienced riders will chip in on this one.

Somewhere near your home there is surely some type of equestrian establishment that would let you ride a gentle horse for an hour at a safe pace, for a fee of course. If the ride of an hour gives good results, then try riding again for 2 full hours a few days later. There is considerable difference in how the body responds when you double the time. That way you can guage how your body might handle a 6 hour trip.
At 65, I would not have tried riding for that long, even though I had a horse when I lived on a farm as a young teenager.
Conventional wisdom says you will be sore and find walking difficult for several days after your trip unless you have done something to prepare. We do not usually sit that way, and there is not much you can do around the house that will prepare you to sit for hours with your legs in a straddle position. Hopefully those mules are gentle enough that you do not have to grip with your knees to stay in the saddle. If you do, bear in mind that if you have not ridden frequently, you simply don't have the muscles and the toughness to withstand the prolonged riding posture and effort. I am hoping some experienced riders will chip in on this one.

I am an experienced rider who is under 30 years old, and even for me, 6 hours in the saddle without a break would be quite difficult. (Themost I canmuster is 2 hours straight!) I cannot imagine a 65 year old person who has little or no horseback experience doing this! Let's hope the ride is using western saddles- they are much easier to sit on for long periods of time.

My recommendations:
1. Go to a saddle store and buy a "seat saver", which is a fleece cushion that covers the seat of the saddle. This will cushion your hipbones a little.
2. Do bring lots of Advil or other NSAIDs, and start taking them before your ride begins.
3. Wear comfortable clothes- well-broken-in blue jeans, a hat to keep the sun off your face, and comfortable foortwear. I always recommend boots for safety when riding, but if you don't have any, then just wear comfortable shoes.
Good Luck!!