@BirdDancer :

"Would a cream or gel with arnica help your back? Voltaren is now also available OTC. It required a prescription, in the US, until just recently. A little of this stuff goes a long way. My husband uses both, often. He has various back pain issues and they help him a lot, especially well the Voltaren."

Great suggestions! I have used lots of both in the past. I am happy to see Voltaren Gel as an OTC option now.
My favorite for a long time now: Penetrex - This is a very potent formulation of arnica with other ingredients. I took this to my favorite compounding pharmacist and he was very impressed, telling me that type of formulation would cost over $200.00 for the same amount as in the usual Penetrex packaging.
I had initially thought Penetrex is expensive, but then I realized I spend the same to purchase straight arnica lotion/oil.

Your trips sound like a lot of fun! I do understand feeling like they may be too much . I have had great difficulty when simply traveling to different time zones here in the States. I hope it will go well for you.

Love, Comfort and Good Health for ALL