This is really a YMMV kinda thing, but in "off season" for outdoors TT bike usage I have been trying to do some pushups and plank style stuff. 50 to 100 pushups a day. Maybe 2 to 3min total of plank. So, not a ton.....but something.
My position is really aggressive. It's fine for 10mi and a little rough for 25mi, and sucks for longer training rides.
My idea was maybe the planks/pushups would make me more comfortable in the position. I have been blown away the difference. I haven't done anything to bulk up my chest, just really toning what's where and in the abs.
Now I just feel like I'm chilling out when in aero like a triathlete in a comfy aero position.
Other improvement was I wasn't interested in trying out a ton of different sunglasses to get rimless or improve my vision riding TT in training. So I got a new old stock Giro Vanquish mips with visor for $100 to my door. Amazing TT bike training helmet, good vision, aero, quieter than my POS Giant branded helmet I was using.
I wondered why that Giant helmet was so loud in TT training rides..........then saw some female racers using that same helmet in Euro cyclocross races..........hmmmm....perhaps the front looking like a cheese grater had something to do with the noise.
Next up was when I reduced the stack on my Speedplays further by getting rid of the adapter plate and custom drilling them myself.......I forgot to adjust the saddle height stuff. So, adjusted that. Ahhhhh that feels better.
Last thing to do is I need to adjust the Speedplay set screws. The right cleat moves too much pedaling for my liking right now.
But I feel I'll be in a good place for some outdoor TT riding when the weather breaks.