So general protein synthesis is 48-72 hours (with the majority of the gains made in the first 24 hours, from what I've understood). That means a frequency of 2x per week (or possibly more) is ideal.
If I'm relatively sedentary outside of the gym (desk job, suburbs so lots of driving and not much walking) can I potentially increase frequency to more than twice a week?
I'm currently following a Push/Pull style routine, and I've been lifting a couple years. I did push yesterday, pull today, and there's a chance my chest will feel fully recovered by tomorrow. Can I hit chest again or could this be detrimental to my gains even if I feel capable?
Depends. You can overload the body from an overall viewpoint. If you go too hard all gains will decrease even if the muscle itself feels fine just from tax on body.
>>42201075
Pain or soreness has little to do with muscle recovery. It's better to let every muscle rest for ~72 hours before engaging them again. Plus, you wouldn't have the energy to keep up hitting every single muscle 3 times a week, and PPL allows you to hit most muscles hard enough twice a week. It's enough.