why is it harder to put your shoes on in the morning than nightimes?

One of the best ways to get lower back pain and sciatica.

Why does your back hurt more in the mornings? I am going to explain to you why doing certain back exercises after just getting out of bed is one of the worst things you can do for your lower back.
Have you ever wondered why it’s easier to take your socks and shoes off at the end of the day as compared to when you put them on in the morning? Overnight you get taller and during the day you shrink! In fact it has been measured that by the end of the day you can be up to 2cms shorter (Reilly, tynell and troup, 1984). Put simply, overnight your discs fill up with fluid and during the day that fluid gets pushed back out again. It has been noted that 54% of this fluid disperses from the discs in the first half hour after waking.
Here is the important part!
That extra fluid in those discs puts a lot more stress on the spine and its ligaments. In fact, Adams and colleagues have measured that the disc bending stresses are increased by 300% and ligament stresses by 80% in the morning compared to the evening! It has also been well documented that a great majority of lower back injuries happen in the mornings.
Here is the tip:
Avoid full lumbar flexion in the mornings. You should already know that you should bend at your hips keeping your back straight (retaining the inward lordotic curve) to avoid putting pressure on your discs and ligaments. In the mornings it’s even more important. Did you know that by bending forwards at the hips with a straight lower back puts virtually no stress on the discs or ligaments? However, if you bend at the lower back putting the spine into flexion the shearing forces that you put on the discs and ligaments are enormous. This is one reason why many people bend forwards just to pick up something light like a pencil and ‘bang’, their back ‘goes out’. It is simply the straw that broke the camels back. It is the same with a person who has a heart attack, the plaque builds up over years and then one day it just happens out of the blue seemingly. Your back can only take so much. Whether its bending forwards poorly all day at your job or lifting poorly or slouching, all of these have cumulative effects on your ligaments until finally your back gives in and ‘goes out’. And it’s completely avoidable!
Therefore if you like to go gardening in the mornings and bend forward pulling out weeds, make certain you are either bending at the hips or go down onto your knees or if you can, get into a squatting position to protect your back. Another alternative is to bend forwards the way golfers pick up the ball. That is, have a straight back and bend forwards on one leg with the other leg extended behind you which acts as a cantilever. It’s an excellent back-saver.
I have written in other posts on lower back pain that bringing your knees to chest, touching your toes with a rounded lower back, rolling up into a ball etc puts enormous damaging forces on your lower back discs and ligaments and you should not do them-period. If you do these first thing in the morning you are putting yourself at an even higher risk of damaging your back-300% higher!
Ok, so…

No slouching, no bending forward with a curved lower back and definitely no sit ups!

But for now,

Rest assured I am watching your back