During development, the team found it difficult coming up with a way to have Sonic compete in the aquatic sections because he is unable to swim. They originally thought of giving him a kickboard, but eventually decided that it "wouldn't look very cool." They instead decided on giving him a life-jacket, and making sure his head was always above water.

On a similar note, Peach and Daisy were originally going to have swimwear designs. These designs were rejected by Nintendo, but when fans stated it was strange no one wore swimwear, they were later added into Mario & Sonic at the London 2012 Olympic Games.