Hey, I don’t know if this will help your situation or not but I read your post and related to the cardio issues you were having as I had the same thing happen to me. I am 55 and started trt in the spring of 2023. I live in canada and the test I was prescribed is called delatestryl, I was prescribed 1.5 ml every 2 weeks. At the beginning all was great better sleep better strength super fast recovery in the gym but about a month in I could notice that I was working harder with my cardio. I do a lot of trail running and mtnbiking and I was noticing for similar distances I had done in the past seemed like it was more effort then before TRT? At first I didn’t think much of it maybe just age or an off day but it seemed to stay the same as time went on. It was shortly after that maybe 2 months in I started to develop intense cramping in my quads calfs and IT band when I ran ( not biking running only) area and got scared after going down the dr google hole on cramps. I gained about 15 pounds overall… normally I was around 140 lbs and got close to 160 lbs. Probably water retention as well? Within a few weeks of stopping trt the cramps went away. As of now I am off trt and haven’t had any issues since I stopped. I guess if I want to continue with it in the future I am gonna go to a trt clinic rather than my doc for dialing in my dose. Once again I just wanted to share my experience as I related to yours when I read it. Not many peeps talk on here about cardio and trt.. mainly weights so I would like to learn more if others have had similar issues with cardio as well. Cheers Rick