User blog comment:Henshin1971/Ultraman(Manga)/@comment-6500929-20130215133110/@comment-5527544-20130215141158

Check mangahere.com. The story is that after ultraman merged seperated from Hayata, Hayata retained Ultraman's genes giving him super human strength, durability and agility even into old age. He later has a son named Shinjiro who inherits his father's abilities and dones powered armor to fight aliens