During which phase of hair growth does the hair follicle become most active?

The most active phase of hair growth occurs during the late anagen phase. In this stage, the hair follicle is engaged in rapid cellular division and growth, leading to the development of a thicker and stronger hair shaft. The late anagen phase is characterized by the hair being deeply rooted in the follicle and receiving essential nutrients and blood supply, making it the optimal time for hair growth activity.

In contrast, the telogen phase is a resting period where the hair is not actively growing, while the catagen phase represents a transitional stage where the hair follicle is undergoing changes but is not actively growing. The early anagen phase, while it marks the beginning of hair growth and reactivation of the follicle, is typically less active compared to the late anagen phase, where the actual growth and maturation of the hair are most pronounced. Therefore, the late anagen phase is crucial for understanding hair growth dynamics and the overall cycle of hair production.