What is the limiting factor when performing high intensity anerobic activities?

Glucose is the limiting factor when performing high intensity anaerobic activities.

Exercise can cause profound changes on glucose homeostasis in the body. For those people who have type 1 diabetes, aerobic exercise usually causes blood glucose concentration to rapidly drop. On the other hand, anaerobic exercise may cause it to rise, thereby making glycemic control difficult and challenging. Continuous glucose monitoring can increase self-efficacy for those individuals who are prone to hypoglycemia and hyperglycemia.