Most doctors would give this same advice (not I’m not a medical doctor). But it holds true in this case. If you can pin point what exercise or movement really makes your tendonitis feel worse, then try and avoid such movements. If there’s a particular shoulder or bicep or tricep movement that really turns up the burn, then for a short time period, don’t do that exercise.
2 - Ice
No more than 20 minutes. My own experience has been that 10 minutes works well immediately on the area when it’s inflamed and sore. You can use ice multiple times a day but only for short durations as you feel necessary.
3- Heat creams
This can be combined with the ice treatments. Most of the times, I have found that using a heat cream like AST Biofreeze, Tiger Balm or any other type of cream works well in a pre-workout situation. Warming up the area feels good. This can be used during the day and multiple times.