The human body is likely to have a fast metabolism after exercise, but this is relatively normal, because exercise accelerates the body’s blood circulation to cause the body to have a faster metabolism. Of course, some diseases may also cause the body to have a faster metabolism, such as diabetes. Diabetes is a hypermetabolic disease, so patients with diabetes will show accelerated metabolism and will experience symptoms such as excessive drinking, urination, overeating and weight loss. Be sure to check your blood sugar to see if the accelerated metabolism is due to diabetes. Hyperthyroidism is also a hypermetabolic disease. Patients can have thyroid hormone tests and thyroid ultrasound to see if they are suffering from hyperthyroidism.