I need some advice.

I am male, 53 years old, 6.0’ tall, 185 lbs, and approx. 20% body fat. I am considering going on TRT, but I am concerned about what target testosterone level to seek, based on my body type and probable historical testosterone levels .

I recently had my testosterone tested, and my levels came back at 365 ng/dL for serum testosterone, and 8.5 pg/mL free testosterone (direct). I have never had my testosterone tested previously, so I have no idea how my current level compares to when I was younger. However, now, I am clearly at the lower end of the normal range. This confirms and corresponds well with what I have been feeling for the past few years – tiredness, fatigue, low sex drive, etc. I have read a fair amount on TRT, and I do think I would most likely benefit from treatment.

I have read that many TRT programs seek a 900 ng/dl level for treatment. However, I have been doing some additional reading, and now I have questions about what my natural testosterone “setpoint” should be.

I have always been fairly athletic – I would say easily in the top 20% of the general male population. I have always tended more to endurance based activities – running, cycling, rowing, etc. But, I have decent musculature – despite never having lifted seriously, I was recently able to get to 270 bench and 160+ OHP within 5 months of lifting moderately. I have always had a normal to above-average sex drive.

However, I have traits that suggest that I could have a naturally lower testosterone baseline level. Very little body hair, a thinner, more wiry body (well, maybe not so much anymore ), full head of hair, late physical development (very late teens). I do have a deep voice, however.

I am looking to get back to feeling similar to how I did 10 years ago, but I don’t wish to fundamentally change my body type or hormonal profile, if that makes sense? I have read some anecdotal accounts that suggests that certain body types (endurance-type athletes, for instance) may have naturally lower testosterone levels. I have read other anecdotal reports, and simple bell curve distribution would support, that some men have natural testosterone baselines of, say, 600 ng/dl testosterone, with normal physical and masculinity characteristics. Then, there might be others whose natural testosterone baseline is closer to 1300. I am not sure one type would do well at the other extreme, or at a middle-range 900 level.

I am seeking your advice on 1) is the concept of lower or higher testosterone “setpoints” a valid one?, 2) what is the best way to determine what new testosterone level to shoot for? If I am a natural “600” guy, and I get boosted to 900, will that in some way upset my body’s natural preferred equilibrium? I realize it is difficult to answer this question definitively, but I would appreciate anyone’s thoughts and advice.

Thank you.