A statement from the club read “We’re delighted to reward the immense contribution Adam has made to the club.
“As a player, we think he has a very unique skillset – incredible stamina and determination which compliment his qualities at both ends of the pitch.
“As a person, he has embraced the club’s philosophy superbly and become an amazing role model for his team-mates, leading by example day-in, day-out.
“He’s a huge asset in so many ways and we know our supporters will share our happiness that he has committed his future to us.”