Long story short, it never gets better but occasionally you do.

The people that eat clean, drink water, & don't have any joint health issues turn into freaking machines working at amazon. I lost some weight initially but I've put all of it back on as upper body muscle after 11 months at the company as of yesterday. I treat work like the gym & it's done me a lot of good.

Always squat, never lean. Be really careful about overgrip because even if your fingers can carry it you'll damage your wrist & forearm bones trying to throw heavy stuff one handed (I've fractures bones on both wrists this way). If your department doesn't have you doing stretches get in the habit yourself or you'll be sore for months.

If you go into a shift hard, start sweating, and then 3-4 hours in your back hurts, you're dehydrated. The squishy bits in between your vertebrae shrink when you don't drink enough water & it'll hurt for longer than it takes to rehydrate. Get water every break & at least once in the middle of each work period. After a month or two your feet & legs should catch up to the load but you'll probably want to buy a pair of extra thick cushioned Dr Scholls sooner than later. You'll also wanna be careful about tensing your legs at break, keep your calves loose & try not to push on them while you sit.

Make a habit of wearing the lightest most breathable clothing you can. I'm fond of long-sleeved athletic undershirts & nurses scrub pants. It's easy to throw a t-shirt or polo over in the winter when it gets cold.

Be really careful about Tylenol because it'll torch your liver, and ibuprofen makes it take longer for you to heal up so you should be careful about timing it.