https://www.nejm.org/doi/full/10.1056/NEJM199607043350101?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub 0pubmed
"We randomly assigned 43 normal men to one of four groups: placebo with no exercise; testosterone with no exercise; placebo plus exercise; and testosterone plus exercise. The men received injections of 600 mg of testosterone enanthate or placebo weekly for 10 weeks. The men in the exercise groups performed standardized weight-lifting exercises three times weekly. Before and after the treatment period, fat-free mass was determined by underwater weighing, muscle size was measured by magnetic resonance imaging, and the strength of the arms and legs was assessed by bench-press and squatting exercises, respectively."
Please see the chart attached. The group receiving exogenous testosterone without exercising, gained more muscle mass than the group that exercised and did not take exogenous testosterone.
I saw the chart and i read the study. Two things; if we are doing any kind of molecule study - then simply tag and track the molecule, the exogenous one, see where it goes, see what it does. We now have SMS (single molecule science) to get a better sense of what these exogenous molecules do once they meet up with cells, once they breach cells, if breaching actually occurs, and what they do inside the cell.
That study doesn't need 40 people. That study does away with so much assumption and speculation.
The second issue is that just because we inject or eat something, we should not assume that the molecule knows where to go and what to do once it "gets' to where we think it is going, and again do what we think it will do. The body doesn't work that way. Testosterone, especially because we make it ourselves is certainly not going to all of a sudden make a B line to muscles and start having them grow. A teen can exist with zero muscles - totally skinny - yet have raging hormones which include testosterone. Science must always mesh with reality.
On my blog site i have an article called "tag you're it..." It speaks exactly to these studies and how the science and the math doesn't add up - as regards how we get bigger, stronger muscles.