A muscle may resist the uptake a glucose for a lot of bad reasons, but for one very good reason – it has too little glucose demand.
Every day: Fast for at least 18 hours and exercise during that last hour of fasting and see if the insulin resistance begins to decrease and eventually goes away.
In more extreme cases, we may have to fast longer and exercise harder to reduce the plasma concentration of free fatty acids, which itself reduces insulin sensitivity, to see much of an effect. But the principle is the same:
To normalize blood sugar permanently:
Create glucose demand by always fasting and exercising before feasting.
Give the glucose somewhere to go!
If you can at least stroll after feasting, even better. Otherwise, one can be reasonably sedentary during the fasting. Just do not go out of your way to avoid exercise and routine movement during the fasting.