I understand your suffering. I was there with extreme fatigue, muscle aches, breathing problems and brain fog for 1.5 years. I prayed for guidance and now I am doing well and I wish to share what I have learned to hopefully help others.

Some over simplified basics: Our muscles are made up of tissues that are made up of cells. The cells need constant recharging to create energy, similar to rechargeable batteries. A constant resupply of oxygen to our cells is needed in order to create the energy.

Here are excerpts from an article by Medical News Today:
“The study shows that when the mechanism that releases nitric oxide from the amino acid binding site in the hemoglobin is working, the blood vessels dilate and allow oxygen-rich red blood cells to flow into the tissue.”
“Essentially, blood flow cannot autoregulate (increase) without nitric oxide. In terms of developing future therapies, the goal must be restoring red blood cell function, complete with nitric oxide delivery capability. As for the nation’s blood supply, the blood should be replenished with nitric oxide.”
https://www.medicalnewstoday.com/articles/292292#Implications-for-blood-transfusions-and-the-nations-blood-supply
A key factor for this process to get oxygen into our cells and tissues is the ability of our bodies to produce nitric oxide. The body naturally produces nitric oxide as the end product of a conversion process of dietary nitrates and vitamin C. One of nitric oxide’s functions is to relax your blood vessels, which improves blood flow and oxygen supply to our tissues.

Obtaining sufficient nitric oxide (NO) takes a constant focus of how we can increase NO by consuming vegetables / supplements with nitrates and avoiding what decreases NO.

We need to consume vegetables with nitrates and have vitamin C from citrus or supplements. Some of those vegetables are beets, kale, spinach, bok choy, celery, cocoa, honey, broccoli, cauliflower, and carrots. Add citrus, like orange slices, to get your C naturally.

The supplements are L-Arginine and L-Citrulline that create NO. They can be taken together, but limit to 9 grams total per day. I take between 3 and 8 grams per day depending on my level of activity / exertion. Remember to take them with vitamin C. I limit my vitamin C to between 500 mg to 700 mg. I had stomach bloating / pain at 1000 mg. (If you are on medications, check on whether these supplements will interact with your meds.)

Nitric oxide production decreases as we age. Aging is not an option, but there are some things we can control. Nitric oxide (NO) production takes place in our mouths and we can decrease that ability by 1/3 if we use mouthwash. NO production will decrease with if we consume high salt, high fat or high sugar.

I do have concern about medications decreasing NO production, including the Covid vaccine. (I had 4 shots.) I went on a pharmacy site and searched for meds that decrease NO production and they had a list of almost 800.

What got me started on NO was an Italian study that tested L-Arginine and vitamin C for long covid. They found it improved symptoms. I tried it and I found I no longer had PEM. That encouraged me to continue pursuing further knowledge. I would encourage you to do so.