Taking insulin if you're not a diabetic is a really bad idea. By itself, it won't do anything except make you hypoglycemic, potentially put you into a diabetic coma, and make you fat.
In general terms, if you're fast blood glucose is normal and your HbA1c is normal, then don't worry about insulin resistance.
There seems to be a number of otherwise healthy, lean, very physically active people on this board that are concerned about insulin resistance. If your blood chems are normal, worry about something else. If your a fat, sedentary individual, then worry about insulin resistance, or if you're a lean Type II diabetic, worry about insulin resistance.
Subtle differences in how we respond to insulin within normal limits is unlikely to affect performance or physique.
W6