Michael Phelps spent his first day of retirement in the pool

Michael Phelps is enjoying some well-deserved downtime following his winning streak at the Rio Olympic Games. He kicked off his retirement with fiancée Nicole Johnson and their baby son, three-month-old Boomer.

The champion swimmer shared a snap of himself spending quality time with his family as the loving couple fuss over their son while in a swimming pool, with Michael captioning the post: "There's nothing like being back home!! Great way to spend my first day in retirement!!"

TAP TO VIEW GALLERYMichael Phelps with wife, Nicole Johnson and their child, Boomeer, in the pool Michael has been spending time with his family

He also shared a sweet snap of himself posing with Nicole, and opened up about how much he was looking forward to spending time with her following the Games, writing: "I love spending time together with you!! Thank you for everything!! Can't wait for the next chapter in our life to begin!! Love you!!"

The most decorated Olympian of all time's fiancée took their son along to cheer him on during the Games, and even dressed little Boomer is Team USA attire with a 'Team Daddy' T-shirt, writing: "Way to go daddy!!!!" following Michael's wins.

Boomer Phelps Michael's three-month-old son Boomer has been watching his dad at the Olympic Games

During her time in Rio, Nicole also chatted about the couple's future wedding plans, telling Access Hollywood: "We have a date. It'll be small and intimate for the wedding and then we're throwing a massive bash for everyone in the States so we're kind of getting things rolling. I've been planning as we've been leading up to [the Olympic Games]. I think I have the wedding in order and now it's onto the party for fun."

She also joked about Michael as a dad, revealing that she is the stricter parent. She said: "I'm going to be the hard hand and Michael's going to be like 'yeah whatever you want, did mom said yes?'" Michael's mother Debbie also opened up about Michael as a first-time father, saying: "He talks about how he wants to be the best dad he could be, and just to watch him three months on...it's just been heart-warming."

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