As someone who gets tried easily by a lot of things, mostly as a result of my condition, I have come up with ways to stay on top comfortably. Here are a few things we do that works:

- Do a backwards cowgirl, lay down on him (your back to his chest), or have both of you on a slight recline. This makes the position more comfortable, and allows you to 'grind' on your good good spot ;), while also giving him ability to thrust with minimal effort (extra points for bouncy beds)

- When on top for riding, you can again use a bed for 'bounce' so that you're not in a constant motion. You can also again, grind when you run out of breath instead of up & down.

-Lay on him (chest to chest) and just kind of... let your hip do the work. If you get sore or out of breath, you can take a breather by kissing, touching, additional foreplay actions, etc.

- Push your bed towards a wall, so that you can put your hand flat on the wall while sitting on that D. Raise yourself a bit, then use the wall to push yourself back onto him. On the same note, bed frames or couch backs are great to pull AND push yourself back. Your legs do minimal of the work, it's all in your arms!

If you're both tired, mutual masturbation breaks are fun, hot and super super satisfying!