I got a standing desk as well. 
I generally alternate between exercising for strength and exercising for building muscle (hypertrophy) - about 6-8 weeks for each goal. I used to ignore hypertrophy, until I learned that muscle mass decreases approximately 3-8% per decade after age 30..
When I train for strength I use my Isochain or practice calisthenics at high enough loads to emphasize strength over hypertrophy… If working with the Isochain, I follow a simple routine, which is to test my 1-rep max force, then work at 70% 1-rep max for 6 sets of 6-second holds.
Hypertrophy training generally involves tiring the muscles out. The load should be at a particular level to stimulate it - if you can do 100 wall pushups before your muscles fatigue, this is unlikely to stimulate as much muscle growth compared to doing 20 pushups on the floor, which is a position that imposes higher load than pushups on a wall. Debate seems to be over what that load should be - some insist on high load, but if the load is too high you may stimulate strength gain over muscle gain.
I am currently testing a hypertrophy routine on the Isochain. Instead of 6-second holds, training is done at a load low enough to allow for 20-45 second holds, with the goal of reaching muscle failure within that time frame. After this current routine, I’ll try the Geoff Neupert Easy Muscle program for kettlebells and calisthenics.