How does the time-released insulin humulin work in the body?

Not time released: Humalin is a "long acting" Insulin with a peak at 8-12 hours. It peaks at dirrerent times in different individuals as well as interpersonal variation day to day which is why it is difficult to regulate hepatic glucose production. A truely time released or better stated: even dose Insulin like glargine (lantus) avoids peaks in Insulin and lows in glucose and is therefore safer.