struggling to warm up after day off

i love a rest day, and i’m pretty good about doing some walking and not being completely sedentary, but MAN do i struggle to warm up the day after.

i had a big workout day sunday (ran 8km then did full upper body workout), enjoyed my monday off, went for some walks and got 10k steps in, but this morning when i started my incline walk on the treadmill, i literally felt like i was starting a diesel engine in the cold. no particular pain or soreness, just general bleh all through the body. by the time i started jogging i was like holy christ have i ever even worked out before why does this feel so hard?

one of my favourite parts about working out is the warmup and feeling the cardio system switch on and get that tingly body high. when i’ve worked out in the past 24 hours i feel that pretty quick and it’s like my body is primed to get going.

is there an actual metabolic shift that happens on a day off? i don’t change my food consumption at all in terms of content or quantity. tips would be appreciated if there’s something small that helps