Mom's legs used to get tired easily after she started throwing clots. You might want to get the tiredness checked out.

If I stand still, my legs hurt, but at Christmas, I spend a lot of time standing on my legs with charity work, I try to move around instead of standing in one place,I have music in my head and keep time with my feet. I do not have clots like my Mom and it is pain not tiredness as I have arthritis in both knees and ankles. so not the same thing. I wish you luck but suggest googling.

They are available in knee length. A good pair is not inexpensive, but worth the expense if you're on your feet frequently.
If handled gently, they can last a long time. If worn under slacks, a slight run won't matter.

The can be purchased in some large grocery stores, large drug stores or a medical supply store.
They help keep blood flowing ip & down the veins and arteries.

Also, slighting bending the leg at the knee from time to time relieves the pressure on knees and leg muscles.

Why are you standing in one place for any length of time?

Do you have a job that requires that? Can you change the job in any way?

At the minimum, move around. Walking a bit, even though you are still on your feet, should be much easier on your legs than standing completely still. This would be true if you were 22, rather than how ever old you happen to be.

It is also possible that you need shoes with better support. I cannot begin to address that issue, and it may well be very difficult to find a shoe person who can help you with this.

Standing to prepare it, standing to cook it, standing to put all the stuff out, and standing to get everything put away.

3-4 hours on my feet make me not hungry. I like when they come for coffee...

My suggestion is don't prepare any meals that require chopping, slicing, frying, baking, basting, and lifting heavy pans.

And don't read long books standing.

I always feel decadent buying it, but if I buy unprepared stuff it just rots in the veggie area of the fridge

I found out that I have "flat feet" and standing or walking is more comfortable if I put inserts in my shoes (slippers and boots too) which raise my insteps.

when I first discovered I had this condition, someone would suggested a podiatrist, who said he could make me inserts which would cost something like $85.00.

The ones I buy in the drugs store for $5-15 work just fine.

I have a couple of bad knees, to use a non-medical term - some days worse than others. I started researching floor mats for my kitchen and saw an ad in a catalog from a company I trust, based on other high quality products I've bought from them. Their mats were more expensive, but over the decades I have come to believe that you get what you pay for (providing you do due diligence on the manufacturer & product first) so I decided to try one - here's a description of it:

I live in an older house with the original kitchen - no dishwasher. To put in a DW, I'd have to redo all the cabinets - just too expensive, so I spend a lot of time standing to do the dishes. I put the first mat in front of the kitchen sink. It was so terrific, I added three others - in front of the stove, the refrigerator and the counter where I do most of my food preparation. This type of floor mat is perfect. It is heavy enough that it stays in place and the edges remain flat on the floor, thus NOT creating a fall risk or trip hazard. I've had them for over a year and they are holding up just fine, and the edges absolutely stay perfectly flat and don't curl up. I'm about to order another 6 foot wide one to put in front of my washer/laundry tub/dryer in the laundry room, which has a concrete floor.

One of the purchaser's comments on the website reflects my opinion of the product:

Widths vary from 3 to 9 feet, depending on the pattern you choose, and there are multiple patterns in 6 colors. I hesitated to include the name of the company on this post, because I don't think DU should be used for advertising, but I noticed in another thread that people were recommending particular insurance plans, so what the hay!?!? Here's the link:
http://www.frontgate.com/ProductSearch2#w=anti%20fatigue%20comfort%20mat