Fitness

If you are aren't recovering properly yes. Be sure to stretch and drink enough water.

I stretch 12-15 minutes every morning. 3 sets of 4 or 5 stretches. Its amazing how tight I start and how loose I feel afterwards.

Hydrate, including electrolytes. Stretch. Eat proteins and green vegetables. Supplement magnesium, glucosamine and possibly arginine & glutamine. Wear high quality footwear.
https://youtu.be/sOuKeVuej9E

I used to have this problem. For me the main fix was making sure I ate enough fish and got my daily need for omega 3 fatty acid. An added improvement came a few months later when I started doing daily stretches and flexibility exercises.

You don't mention your age, so it's hard to grasp any straws.

Try stretching immediately before and after work and also before you go to bed.

Check out this link for a bit of information.

If you don't want to check the link, basically it says to drink water and stretch. But there is a name for it! DOMS

Eat, sleep, and hydrate. Make sure you're getting enough electrolytes if you're sweating a lot. Try and calculate calories, you might not be getting enough for your activity level. Good luck, it's hard but manageable. If I had to guess I'd say the main thing is hydration and electrolytes, since you have got over the initial hump. If I screw that up on one day, you can guarantee I'll feel like shit the next.

Try making up a mix of salt according to the WHO reduced osmolarity ORS recipe, the proper one with the potassium. Mix it up at something like one quarter to one half the strength they recommend for dysentery, roughly ¼-½ teaspoon per litre. You don't have to add the sugar, assuming you're eating properly during the day it won't be necessary. I'll add a bit of sugar-free squash concentrate and it just tastes fruity, not like drinking salt water.

I also had to up my carbohydrate intake to the level of an endurance athlete, which is counter-intuitive if you're used to being sedentary. But this was for heavy groundwork and construction, like 700g+ carbs per day. Might not be necessary for you but the difference was astonishing, just keeping that muscle glycogen topped up.

not sure if this anecdote is relevant to your situation, but after a very sedentary lifestyle for many years (im 37), I started a job which requires quite a lot of heavy lifting, and I've definitely noticed stiffness and pain in the muscles I'm using most, mainly my fingers and arm muscles. I can't clench my fist without pain and I've also noticed that I lose circulation in my arms much more readily, sometimes just from sitting in one position for too long.

not sure what that's about.

I’ve found it to be the opposite; if I don’t move enough for long enough, I get stiff and sore and any existing injuries feel worse. I think it’s at least partly due to my job, as it requires sitting for longer than a human being should.

Having done manual labor before changing careers, my experience aligns with what others have already said: hydration and stretching are your friends. To add to that, I found supplementing with creatine and BCAAs to be helpful when I was a package handler. Creatine is ridiculously expensive now, but might be worth the price if it makes you feel better.

ETA: hydration matters not just during your shifts, but also before and after work. If you don’t do this already, try drinking a few glasses of water before bed and see if it makes a difference in how you feel in the mornings. I tried it for a few days and it made waking up less painful, so I try to make sure I’m well-hydrated before bed.

It means you need to eat more, especially the right proportions of protein and carbs. You're probably eating the same as you did when you were sedentary, which means that your muscles don't have the required nutrients to recover and heal. Eat more food today and I bet the soreness goes away within hours.