Sorry mane I got nothing on that. Have no idea what changes you see under the microscope and couldn’t understand or explain them anyways.
All I got is multiple sources on the efficacy of muscle biopsy for detection but invariably commenting that the invasive nature of the test makes it impractical and athletes would kick up a fuss. WADA and other agencies have no reason to push hard for it because it’ll turn out badly for them. Either they start up a shit storm with athletes worldwide or half of them test positive and WADA gets embarrassed.
If you can make sense of it:
Effects of anabolic steroids on the muscle cells of strength-trained athletes.