Twenty-two time Olympic medallist Michael Phelps is entered in five events for the United States trials as the swimming superstar eyes another successful Games.

Phelps is scheduled to swim the 100- and 200-metre butterfly, 100- and 200-metre freestyle and the 200-metre individual medley, at the meet held June 26-July 3.

While Phelps is allowed to scratch any event he sees fit, the five events could result in eight in total for him in Rio de Janeiro, as he is expected to be part of each of the three USA relays.

Phelps' American rival, Ryan Lochte, is entered in six events, the 200- and 400-metre IM, 100- and 200-metre freestyle, 200-metre backstroke and 100-metre butterfly.

On the women's side, current world record holder in the 400- and 800-metre freestyle events and defending world champion in the 200-metre freestyle, Katie Ledecky is also entered in the 50- and 100-metre freestyle as well as the 400-metre IM.

While the IM is not a strong event for Ledecky, the sky is the limit for the 19-year-old who is expected to take home at least three golds in Rio.

Looking to make her fourth Olympic Games, Natalie Coughlin is entered three events, the 50- and 100-metre freestyle and the 100-metre backstroke, an event in which she is listed as the top seed but Missy Franklin holds the American record.

Franklin is also entered in the 100- and 200-metre freestyle and the 200-metre backstroke, for which the 21-year-old owns the world record.