500ng/mL IGF1?

I was diagnosed with low-T a year ago, and have been on TRT since then, with some symptoms improving (strength, body fat %), others not changing (fatigue, inability to recover from strenuous cardio workouts). I had a blood test last week that revealed 500ng/mL of IGF1, about 2x the max for my age group (however, 500ng/mL is just the high end of normal for a teenager). I just had an MRI, and found out I have a 8mm pituitary adenoma.

I’m wondering how high of IGF1 people who supplement HGH test out at. I’ve seen recommendations to keep it to 300-400, but I don’t know what the negative effects of slightly more than that are. Apparently people with acromegaly routinely have IGF1 levels 5x-10x the normal range. I’ve got slight visual indications of acromegaly (6’4", 2XL gloves, a bit caveman looking), but I’ve been that way since I was a teenager and it doesn’t bother me.

The thing that prompted the latest round of blood tests was that I recently took a VO2max and blood lactate threshold test. My VO2 Max surprisingly tested out above average, but my lactate threshold test was abnormal: my blood lactate level didn’t go up much with increasing treadmill speed (only hit 3mmol/L, usually people can get to 8-12mmol/L), but my heart rate went up, and I was unable to keep up with the increasing speed.

So, I know I need to address the tumor, but I’m wondering if I can expect increased or decreased athletic performance once I have a ‘normal’ amount of HGH? I had a cardiac ultrasound, and my heart wasn’t enlarged and didn’t have thickened walls. Also my above average VO2Max test result makes me think my heart’s fine, it’s something related to the weird blood lactate numbers that are hurting performance, and I haven’t seen any reports of HGH leading to poor performance (unless in cases of acromegaly, with 5-10x normal HGH levels, and enlarged hearts), so I’m struggling to stay positive about this pituitary thing really being the cause of my continuing symptoms. Seems with 2x normal HGH, I ought to be a super athlete, and sadly that is not the case.