The five faculties that gradually weaken with age are: self-education, Vital Sheath, Pranamaya Kosha, Manomaya Kosha, Vijnanamaya Kosha, and Anandamaya Kosha
The signs of healthy development of Pranamaya Kosha include: enthusiasm, ability to use voice effectively, suppleness of body, perseverance, leadership, discipline, honesty, and nobility
Activities that challenge one's intellect develop Vijnanamaya Kosha, such as debates, problem-solving, study techniques, small research projects, evaluation, and appreciation of books