Hi, I would like to add the tone together with the PIN YIN, for your reference. :)
1 游泳者you2 yong3 zhe3 , or 游泳的人you2 yong3 de ren2
2 both the 游泳选手and 游泳运动员 are used on describing athletes, and the tones of them are 游泳选手you2 yong3 xuan3 shou3, and 游泳运动员you2 yong3 yun4 dong4 yuan2.