Athletes/weightlifters abusing insulin?

Factual Questions
1

I’ve heard that it’s not that uncommon for weightlifters and professional athletes to shoot insulin prior to training; supposedly this can enhance their performance. Is this correct? How could this work?

I really can’t see how taking insulin could help anyone train. A non-diabetic person who takes insulin would become hypoglycemic shortly after injecting, causing fatigue/weakness. And if this actually did work, I suppose it would become relatively commonplace, since there isn’t any way to test for it.

2

as I understand it insulin aids in transfer of glucose from the blood to the cells. A person working out would deplete glucose in their muscles and thus an even greater gradient would be created. More insulin would mean more glucose can equilibrate with the muscle cells faster.