I've been reading here for a while... time to get involved. Thanks for your post!
I am 55 and have been on TRT for 5 years and synthroid since 2013.
TRT is working for me and I cannot be nearly as active without it. In 2012, my initial T reading was 290 and I had all the bad symptoms. I had been active with physical activities (skiing, Mtn Biking, swimming, weight lifting). I was probably very low T for nearly 2 years as motivation declined and various aches and pains (tendonitis's) accumulated. The killer for me was the mental fog and constant lethargy.
Initial dose was 1ML weekly of the 200mg cypionate. After 8 weeks, my dosage was reduced to .9ML weekly. A year later, I was started on synthroid. At the time I was in Arizona and had decent doctors to work with. I was able to get good testing and learned a lot. I also participated on the Men's health board and learned a lot there.
I am in Utah now and find good medical care is impossible. I have my appointment next week. I have to argue with my doc to order the estrodial test and the CBC (hematocrit) test. Incredible.
I am always studying my health. Something is always popping up and challenging my lifestyle. As such, I am always reading about TRT. In the past, I have tried to reduce my dose and to inject more frequently. These past attempts failed to improve my situation and I returned to weekly injections.
What is working for me right now, is to very dose by activity level. I have switched to twice weekly injection (intramuscular in the glute, Friday morning and Monday night). When I am highly active, I inject .45ml each time. But, I have months where I am sedentary, over eat, and perhaps drink too much. During this time, I am able to reduce my injection to .35ml. I have been doing this since 3/2017.
I have never read how T utilization can be affected by activity, but a constant dose does not work well for me.
I am active right now. I am MTN biking at elevation nearly an hour every other day... routinely hitting Max Heart rate. I am also swimming nearly an hour a day and weight lift at least an hour a day. I am not a body builder by any means (5'10" and 160lbs.) I just stay fit to maintain my activities... mtn biking and skiing.
Because of my reading here, I tapered off my synthroid and last March and started experimenting with Iodine and licorice root tea. Haven't come to any conclusions just yet.
At the moment, my health challenges are lack of sleep (a problem since 2/2011) and a high resting heart rate... 85bpm (which is why I am re-examining my thyroid issues).
I am committed to maintaining my active lifestyle for as long as possible. TRT is an important part of that...if the medical profession will allow it.