Now that I'm 7 months into taking Orgovyx, I've noticed a slight but noticeable increase in my lower and upper body muscle size. I do 30 minutes of cardio 3 times a week, every other day, and on alternate days, approximately 50 minutes of resistance training 3 times a week. I take Sundays off.

That article surftohealth88 posted above has a section entitled "Exercise intervention program" where they describe exactly what they got their patients to do. They measured the maximum resistance for each patient could perform for each upper and lower body exercise, they call this the 1RM or one repetition maximum, then they designed a program for each patient consisting of sets of 10 reps of each of those exercises starting at 60% of that resistance, ramping the % up and back down so they could gather data. 2 sessions a week, 60 minutes total.

If your exercise program is something similar to what the cited article describes and you are not experiencing results, it is possible you could improve the situation.

The exercise oncologist I studied, Dr. Robert Newton, has been researching how to use exercise to help prostate cancer patients for decades.

The way he suggests, using a pin loaded machine for instance, is to set a resistance light enough so you can perform at least 6 reps, but heavy enough so by the time you've performed 12 reps you feel like you could only do 1 or 2 more before it simply would not be possible to continue. As time goes by and doing 12 reps is getting too easy, increase the resistance by 5 or 10%, making sure you can still do at least 6 reps. He suggests a routine including chest press, seated row, lat pulldown, leg press, leg extension, and leg curl.

I add a biceps curl machine, glute drive machine, and ab/aduction machine to that. It takes me 50 minutes to do my resistance routine. I keep a chart showing what resistance I set each exercise machine for the last time I used it, and as it gets easier to achieve 12 reps, I keep upping the resistance as Newton suggests.

His clinic uses machines that can be programmed to offer a different amount of resistance to each phase of an exercise, i.e. less for the concentric than for the eccentric phase. His research has indicated that this is the most effective way for a patient on ADT to gain muscle mass, i.e. to exercise on machines capable of doing this.

My gym has nothing like this. What I do to partially simulate this is to take 4 or more times longer to perform the eccentric phase of an exercise than when performing the concentric phase. I may not even understand what I'm doing here, but the way I figured it, for instance, during a leg extension, I quickly raise the legs straight out, then take much longer to lower the legs down. A biceps curl is quickly contract the muscles to lift against the resistance, then slowly straighten my arms out. This is my understanding of what Newton suggests. YMMV.

I experienced what exercise experts call DOMS, i.e. delayed onset muscle soreness, which sometimes was especially intense when I started out. Newton says this is not something to try to avoid. It can be a signal there is a problem you need to consult an expert about, but it is also the signal you're doing the right thing. I backed off a bit if the DOMS was severe, but I took it as a signal to slow down the rate of increase in exercise intensity, not as a signal I needed to reduce.

Newton has a book MyExerciseMedicine for Cancer.

He published a short article explaining his views: Prostate cancer treatment with
exercise medicine" https://onlinelibrary.wiley.com/doi/epdf/10.1002/tre.884

Newton, et.al. 2012 "Can exercise ameliorate treatment toxicity during the initial phase of testosterone deprivation in prostate cancer patients?” has a section "Exercise intervention" that describes exactly what he had the patients he was studying do. https://pmc.ncbi.nlm.nih.gov/articles/PMC3519595/

Newton has researched how to preserve bone health during ADT as well. He published "Exercise Mode Specificity for Preserving Spine and Hip Bone Mineral Density in Prostate Cancer Patients". I found the whole article which describes what the patients he studied were required to do, but any link I found just now is only to the abstract. Maybe I sent in a special request for access or something.