Lin earned the nickname "Super Dan" during the peak of his powers and was world number one
Arguably the greatest badminton player of all time, Lin said on Saturday that he would no longer compete for China, giving up on his fading hopes of qualifying for next year's postponed Tokyo Olympics.
But Lin has admitted he has an eye on playing in China's National Games next year - provided he stays in shape.
"If I gain weight in March next year, I won't compete anymore," the 2008 and 2012 Olympic gold medallist said, according to the Beijing Youth Daily.
"If I don't gain weight, I will continue to work hard.
"I also hope to have such an opportunity to work hard to participate in the 2021 National Games.
"So far I have participated in five National Games, so if all goes well, I hope to play another."
Reflecting on the end of his international career, during which he was a five-time world champion, Lin said: "I chose to withdraw from the national team.
"In fact, my mood is very complicated. After all, I have spent 20 years in the national team.
"I can proudly tell anyone that I have played for the country for 20 years, which is something I am very proud of."
Lin earned the nickname "Super Dan" during the peak of his powers and was world number one.
But his form and fitness tailed off in recent years and he was highly unlikely to qualify for the Tokyo 2020 Olympics, which have been moved to next summer because of the coronavirus.