Blood test for run down endurance athlete

Having a physical this week, I am 50 and have been in a year long slowdown, just feeling lousy, no desire. Took time off came back not feeling any better, sore legs almost every day. Have lost 1 to 1 1/2 minutes off my run pace. One time a 2:39 marathon runner, now almost an hour slower, every run is a struggle. What type of blood workup should my doc do? Thanks for any help you can offer.

TSH, Free T3 and T4, the usual iron workups… (hemoglobin etc)… I had
a similar problem, tired after every workout, couldn’t recover, always
tired… I went in after 2 months of this and had a full blood panel
done up, and my TSH came back slightly elevated, turns out that i was
hypothyroid and it was VERY sensitive to TSH levels, took about 8-10
months to get my replacement dosage sorted and I feel literally 100%
better… starting to PB across the board, can handle consistent
training etc…

I’m 44 and had some similar problems along with digestive issues ( bloating and lots of gas ). I had bloodwork done by a dr. who also practices alternative medicine. Turns out my stomach does not produce enough hydrochloric acid. The blood work showed I have to much iron and should donate blood to help lower this, high mercury levels most likely due to some old tooth fillings ( I had them removed ), some of my hormone levels were off and some vitamin levels were off also. At this point most of these conditions are being treated with supplementation and tweaks to my diet. My energy levels are improving now that I take HCL supplements before I eat that helps to break down food so I can absorb nutrients.

it’s always something and every day we learn…SP

Obviously your doc should suggest your w/u…but consider ESR to R/O PMR (polymyalgia rheumatica). Sore legs - consider check CK/CPK? On cholesterol meds? Thyroid is obvious. Depression?

Dave