Muir attained further success as a coach at the 1982 Commonwealth Games with a gold medal for Cameron Henning, and at the 1982 World Aquatics Championships in Guayaquil when Sharon Hambrook and Kelly Kryczka won the gold medal in the duet routine. Her squad won the 1983 Pan American Games gold medal in the team competition. After synchornized swimming became an Olympic sport in 1984, her swimmers Hambrook and Kryczka claimed the silver medal in the duet routine as Carolyn Waldo finished second in the solo event at the 1984 Summer Olympics in Los Angeles. During 1986, Muir stopped coaching the Calgary Aquabelles to focus on the Canadian national team. Her athletes achieved two gold medals in the duet and solo competitions at each of that year's Commonwealth Games and the World Aquatics Championships in Madrid. In 1987, she attained further success when her swimmers took gold medals in each of solo and duet routines at the 1987 FINA Cup.