I periodically change my lifting and cardio routine to keep my body from plateauing and to foster proper muscle growth. However, when the first few days, or even the first week of that change promotes some fatigue and a tad bit of muscle soreness. Usually, I just grin and bear it and the soreness and fatigue work their way out, but in that first week after a routine change, my body is showing me its limits and I may only go 3 times that week as opposed to 4 or 5.
For example: I might do 4 to 6 weeks of 5x5's bench, deads, squats, rows, and military presses (2 days per week) with other smaller muscle group exercises in between those days (2 to 3 days per week), alternating upper and lower body and / or muscle group areas.
Then, I'll keep doing bench, deads, squats, rows and military, but change the sets. For example, on bench, on my 5x5's, I'll do 5 x at 275, then switch to a 12-4-3-2-1-12 with the 12's at 235 and the 4-3-2-1 a pyramid with 4 at 285, 3 at 295, 2, at 305, and 1 at 315, then back down to 235 for a set of 12 (which I usually get failure around 7 or 8). I do similar sets on rows and military, but switch to leg press on a sled in substitute of the squats. The smaller muscle group routines usually stay the same with 3 sets of 10 with alternating exercises (i.e. for triceps, one day I'll do skull crushers, then the next time I'll do push downs on cables). One of the owners of the gym I work out in gave me this routine to try (12-4-3-2-1-12). Also wanted to know if anyone here did a similar workout and what kind of results you got.
For guys 40+, what have you guys done that helps you with these types of transitions in workouts? Also, what type of supplements and / or vitamins, and / or protein powders do you guys use?