MacAdam played for the University of New Brunswick. He then had a short career in the minor pros, playing two seasons (1973-74 & 1974-75).
After retiring, he embarked on a long coaching career, starting with the Sault Ste. Marie Greyhounds in 1985-86 and then three seasons as an assistant with the Detroit Red Wings. He then coached various teams in the ECHL and American Hockey League until 2007.
In 2008-09 he coached the MAINEiacs as a mid-season replacement. At the end of the season he was relieved of his duties as both president and coach.