It sounds like your PMR isn't completely under control yet if you're having trouble walking and lifting your arms. How long have you been taking prednisone? It can take a few days for it to take full effect. I would think once your pain is under control you could start lifting light weights and running slowly. Just be careful not to do too much at first. The prednisone and the PMR can both affect your muscles and tendons and make it easier to cause strains and tears. I learned that from experience. I have PMR and GCA, and have been running for almost 50 years. I went through a bad stretch tapering from 20 mg prednisone down to 10 where my muscles were straining very easily while I was jogging and lifting weights. But everyone is different. You might not have any problems.

Hi @phogan0609, Welcome to Connect. Sorry to hear Mr. Ugly (PMR) has invaded your personal space. I've had 2 occurrences of PMR and was started at 20 mg prednisone for both. Took 3 and half years to taper off of prednisone the first time and 1 and half years the second time. I think being a competitive athlete is a plus for you because I'm guessing you already eat healthy and it's important to stay active as much as you can without overdoing the exercise.

I'm not sure if you are on a tapering schedule provided by your doctor/rheumatologist but you might find it helpful to read through the references in the following discussion:
-- How to Slowly and Safely Taper Off Prednisone but ... no set rules.
https://connect.mayoclinic.org/discussion/how-to-slowly-and-safely-taper-off-prednisone-but-no-set-rules/
If you want to know a little more about PMR, the following discussion has an informative video - Comprehensive Overview Of PMR: https://connect.mayoclinic.org/discussion/comprehensive-overview-of-pmr/

What really helped me manage my symptoms was keeping a daily log of my level of pain (0 to 10) and my dose of prednisone for that day when I got up in the morning. Do you keep a log of your pain/symptoms and doses daily?

I agree with jeff97. After spending months with extreme pain and barely able to function let alone work out I self diagnosed myself with PMR. I took 20mg equiv. of prednisone and the pain was gone in 4 hours. From all my reading 15-20mg is about what the Dr likes to start for treatment. Otherwise they start thinking that maybe this is not PMR and maybe yours is not. Your age will also make the Dr hesitant. GCA diagnosis takes double that dosage. I am familiar that some PMR sufferers have found that a higher starting dose is necessary. If your Dr. is willing to work with you, then maybe try going to 40mg for a 2 or 3 days. The prednisone works on PMR and you should be pain free. Prednisone has a lot of complications so you want to try to taper back as soon as the pain is gone to your lowest possible dose. Within the first 12-14 days you can experiment. After 2 weeks your body shuts off cortisol production and you need to taper more carefully. Once the pain is gone you can start to workout. Be careful since you still have inflammation and are taking drugs to mask it. PMR is not necessarily a life sentence.

For the time being just gently work on range of motion. Then gradually start building back up but this is going to take 6 months or a year in my experience. Going to take some patience which may be a developing skill for you. Cheers.

I was 52 when I was diagnosed with PMR. The difficulty I had with being diagnosed with PMR was because I was previously diagnosed with a type of inflammatory arthritis called reactive arthritis when I was 32. Not being able to lift my arms was the characteristic symptom I had when PMR was diagnosed.

I have multiple autoimmune disorders including PMR and they all responded well to Prednisone. My other autoimmune disorders were more responsive to Prednisone than PMR. A rapid response to Prednisone is not diagnostic of PMR. In my experience, PMR didn't respond very quickly and I needed to take Prednisone daily for 12 years. My other autoimmune conditions responded faster and I tapered off Prednisone again in just a few weeks.

The usual starting dose to treat PMR is somewhere between 12.5-25 mg of Prednisone. Nothing you have said suggests to me that you don't have PMR.
https://www.ccjm.org/content/87/9/549
The key points in the above link are worthwhile to know.

In my case, the last key point that says, "Preliminary studies show possible benefit from tocilizumab, an interleukin-6 receptor antibody, as monotherapy or for refractory cases" changed everything for me. It completely changed my thinking about treating PMR with long term Prednisone.
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Unlike my other autoimmune conditions, PMR typically requires "long term" treatment with Prednisone. The long term treatment with Prednisone is what causes people to develop "additional problems." My overall health and well being declined over the 12 years I took Prednisone daily. In my case, being unable to taper off Prednisone after PMR went into remission was partially caused by adrenal insufficiency which is a side effect of long term Prednisone use.
https://pmc.ncbi.nlm.nih.gov/articles/PMC10257969/
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Adrenal insufficiency is a serious problem. Don't worry about this problem just yet. First PMR must be in remission and your case of PMR doesn't seem like it is in remission yet. Tell your doctor that you may need a higher dose of prednisone or ask them if you can split your current 20 mg so that you take most of it in the morning and the rest in the evening. Maybe try 15 mg in the morning and 5 mg in the evening to see if that works. Tell your doctor though!