Recovery time after a 'break'

i have been working out for about 7 months, and initially I went every other day. like most people though, i made alot of gains in the beginning, and as the gains slowed down, i lost interest in the gym. i started going once every ~4 days, and now when i go, i still ache a couple of days later, enough so that my workout when i still ache is affected. previously it took me around 2 days to recover completely (or feel like i had) but now that time has gone up - and i havent increased my workout intensity or changed protein intake. if anything, im eating more protein now.

i'm trying to start going m-w-f again now, and i was wondering whether it's better to 'ease in' and start leaving 2 days gaps between the gym and then after a while go to m-w-f, or just plow through and accept the less-effective workouts for a while and hope that my body adapts?

i've also recently started running alot more, and found that i ache like a bitch after going on a run (non-treadmill) which is pretty annoying. i had previously run quite alot (an hour or two a week on the treadmill) but now that ive started actually running outside it aches alot more, do i just plow through this aswell or do i have to 'ease in' to running?

im ultimately aiming to do a m-w-f split and then go running tuesday + one day of the weekend. how much does running (around 4km each day?) affect muscle recovery?

do you do the same thing everytime. Stop it!

at any rate I find if I try a new hard exercise I am really sore the first few times and afterwards I'm not. Not sure it indicates slower recovery and not just bmy body being unused to the motion.

as in, do i do the same thing m-w-f? nah, i do chest/bi's monday, legs/tris weds, back/shoulders friday. i havent been doing this particular workout for very long, and i usually switch up my whole routine once every 2 months or so