I have 2 routines: upper body (bench press, pullups, dips, tri-curls, bi-curls, abs and variants) and lower body (squats, lunges, quad raises, calf raises, lower back and variants).
I usually work out for a month and then take a month off. Whenever I start up again, I am sore for a few days. Yesterday (Tuesday), I started again with upper body. Today my chest and lats are marginally sore. Tomorrow, they will be even more sore. On Friday, I will feel like today (kind of sore). Saturday, I will be fine.
Today, I plan on doing lower body. Tomorrow, my upper body will be too sore to do squats (won’t be able to maintain good form) and I really won’t feel like going to the gym at all.
Should I?: 1) stick with the plan and do lower body today, 2) give myself some rest today, but then force myself to do lower body tomorrow, 3) wait until Friday to do lower body, or 4) wait until I’m completely healed and wait until Saturday.
I guess the underlying question is whether the body’s resources needed for recuperation cannibalize those needed for working out another part of the body, minimizing the effectiveness of the second workout (even if it addresses different body parts).