The England international was hampered by numerous injuries, making just 17 Premier League appearances in his first season with the armband.
Henderson, 26, said his minimal contribution on the field meant he questioned himself as captain.
"I've never felt that I didn't want the captaincy but there were times last season when I was very down because I wasn't playing and I questioned my contribution as captain because of that," he said.
"I couldn't help on the pitch as I wanted to and so Milly [James Milner], as vice-captain, had to take the role on.
