Katie Ledecky, Caeleb Dressel, Nathan Adrian, Simone Manuel: The athletes to watch at the 2021 U.S. Olympic trials in swimming

AP Photo/Ashley Landis

At this time last year, Olympic gold medalist Nathan Adrian still didn't have full use of the left side of his body.

It had been a year since Adrian's second surgery for testicular cancer, and he had lost a lot of muscle mass. Surgeons had cut through his abdominal wall five different times to remove about 30 lymph nodes, and while they felt confident they had removed the cancer, that kind of trauma required a lot of recovery time.

"The entire left side of my core just wouldn't turn on. I would try to flex my abs as hard as I can, but the left side would just be soft," Adrian, 32, told ESPN.

The one-year Olympic delay gave him the time he needed to heal.

But for Regan Smith, 19, the postponed Games has been a huge challenge. At the 2019 worlds, she shattered the 200-meter backstroke world record and won gold in that event and the 4x100 medley. She was named the 2019 American Swimmer of the Year and World Swimmer of the Year.

After a lengthy competitive break during the pandemic, she has struggled to return to her previous form. Her first meet back, in November of 2020, was rough. "Things just felt rocky, like I didn't feel smooth. ... I remember feeling like, 'This just doesn't feel like me,'" she said to ESPN.

She's more optimistic six months later, but still hasn't reached her 2019 standards -- and said that she doesn't feel like a lock for an Olympic spot.

At this week's Wave II of the Olympic swimming trials in Omaha, Nebraska, there will be stories of both: those who've been helped by the "pandemic break" and those who have not. The two biggest names in the sport -- six-time Olympic medalist Katie Ledecky, and two-time Olympic gold medalist Caeleb Dressel -- are set to dominate, as expected, seemingly without missing a beat. Dressel, a 24-time world medalist in sprint events, is widely considered the fastest swimmer in the world, and Ledecky, the greatest female distance swimmer of all time.

Ledecky, 24, will look to comfortably qualify in the four individual freestyle events, including her favorite, the 1,500-meter freestyle, while Dressel, also 24, will likely cruise to Olympic berths in the freestyle and butterfly sprint events. Both appear to have picked up just where they left off when competition stopped in 2020, though the pandemic has not been without difficulties: Ledecky, who loved endurance training with male swimmers, was forced to train on her own. While Dressel ran into the same problem others faced early on -- finding a pool that was open, and then working within the limited timeframe he could access it.

Then there are other names you'll remember from 2016: Simone Manuel, who became the first Black woman to win an individual Olympic gold in swimming when she won the 100-meter freestyle in Rio, and Ryan Lochte (of the infamous Rio robbery scandal) who is aiming for a fifth Olympic team.

"There's so many people who I haven't competed head-to-head against in so long," Smith said, "So all of us coming together at this one meet is just going to be extremely special, especially after this year-long pause that we've had."

With over 1,500 swimmers meeting the qualifying times, a first wave of trials was held June 4-7, in which athletes had to finish in the top two to advance to Wave II. (The fastest swimmers overall qualified directly to Wave II based off their times.) Now, at Wave II of trials starting on Sunday, the top two finishers in the individual events, and the top six in the relays, will qualify for the Tokyo Olympics. There are a total of 35 races -- not including the open water 10K -- at this year's Games. Here's who to watch in Omaha this week:

Katie Ledecky

Race to watch: 1,500-meter freestyle

Five-time Olympic gold medalist Ledecky is hoping to qualify for four individual events (200, 400, 800 and 1,500-meter freestyle) and the 4x200-meter freestyle relay at the trials. This is the first time the Olympics will hold a 1,500-meter race, and Ledecky, the world-record holder in the event, is the clear favorite.

In April, at the TYR Pro Swim Series in Mission Viejo, California, Ledecky won the 1,500-meter freestyle, finishing at 15:40:55 -- 26 seconds ahead of the second place winner, Ashley Twichell and the fastest time in the world so far this year.

If she qualifies for all four individual events, she could become the most successful female Olympian of all time. Currently the record is held by Soviet gymnast Larisa Latynina, with nine Olympic gold medals.

Simone Manuel

Race to watch: 100-meter freestyle

When it comes to the 100-meter freestyle, Manuel, 24, is the one to beat. Despite not having competed as much as she would have liked in 2020, the 2016 Olympic champion could become the first woman to win back-to-back gold medals in the event since 1964 (Australia's Dawn Fraser won three titles in 1956, 1960 and 1964). And this is a distinct possibility: After earning gold in 2016, Manuel won the world championships title in 2017 and 2019, proving her continued dominance in the event.

Abbey Weitzeil

Races to watch: 400-meter medley relay and 400-meter freestyle relay

Weitzeil makes relay races exciting. Remember the 4x100 freestyle relay at the 2016 Rio Olympics? Weitzeil blitzed her way through the final heat -- finishing at 3:31:89, an American record -- and securing a silver medal for Team USA in the process. She also swam the freestyle leg of the medley race in the preliminary heats to earn a spot in the final. The team went on to win a gold medal, the 1000th for the U.S. at the Summer Olympics.

Since 2016, the 24-year-old has also been a consistent contender in the 100 and 50-meter freestyle. In 2019, at the Minnesota Invitational, Weitzeil became the first woman in history to swim a 50-yard freestyle in under 21 seconds, clocking in at 20.90 to win the final. She also broke the 13-year American record in 50-meter free in October 2020, then went on to break her own record in November 2020.

Lilly King

Race to watch: 100-meter breaststroke

When you think of the 100-meter breaststroke, there is only one person who comes to mind: Lilly King. She hasn't lost a world event since winning gold at Rio, and set the world record in 2017. At this point, it feels like a given that she will make it through the trials.

Another event to watch her closely in: 200-meter breaststroke. King, 24, has not been as successful in this distance as the 100-meter, but she has produced better times of-late and will likely qualify for the Olympics in this event as well.

Regan Smith

Race to watch: 200-meter backstroke

Smith, 19, is the current world-record holder in the 200-meter backstroke (after breaking Missy Franklin's 2012 record at worlds), and is a strong contender in the 100- and 200-meter backstroke events leading up to trials.

Smith is getting stronger by the day, and making it through the trials to the Games will only mean more to her now than ever before, she said to ESPN. In March 2021, she won gold in the 100-meter backstroke, beating Phoebe Bacon by a full second. She also won gold in the 100-meter butterfly in the same meet.

Caeleb Dressel

Races to watch: 100-meter butterfly, 100-meter freestyle and 50-meter freestyle

Since Rio, where he helped Team USA win the medley and freestyle relays, Dressel has become a sprinting powerhouse. He won world titles in the 100-meter freestyle at the last three championships, as well as the 50-meter freestyle in 2017 and 2019. (He took home the silver in 50-meter free in the 2018 world championships.)

He also holds the world records in the 100-meter butterfly and 50-meter freestyle. Dressel will hope to earn Olympic spots in seven events -- and though he will not yet be able to equal Phelps' historic eight gold medals in a single Games, he could come very close to it.

Nathan Adrian

Race to watch: 100-meter freestyle

The five-time Olympic and 10-time world championships gold medalist is on a quest to make his fourth Olympic Games this year. One indication that he's exactly where he wants to be leading up to trials is his 100-meter freestyle TYR Pro Series win in April 2021 -- his first title since he was diagnosed with testicular cancer in 2019. Adrian, 32, has called the 100-meter freestyle "his baby," and a lot of his attention in re-learning movements has been focused on perfecting that race.

Ryan Lochte

Race to watch: 200-meter individual medley

A lot has changed in Lochte's life since the Rio Olympics scandal, where he falsely claimed that he and his teammates were robbed at gunpoint, and later received a 10-month suspension from USA Swimming. Two years later, he was given a 14-month suspension for receiving a prohibited intravenous injection. Now married and a father of two, the 12-time Olympic medalist hopes to become the oldest male swimmer to represent the U.S. at an Olympics.

In March 2021, at a Pro Series race in San Antonio, Lochte, 36, finished eighth in the 200-meter individual medley and said "it's a good confidence boost" that he's able to make the final round and compete with some of the best in the country. The last race he won was in August 2019 -- the 200-meter individual medley at the U.S. Championships -- immediately following his 14-month suspension. With his experience, Lochte cannot be ruled out as a contender to make the team this year, but still, it feels like a long shot based on the times he has shown.

Ryan Murphy

Races to watch: 100- and 200-meter backstroke

In his debut Olympics in 2016, Murphy, now 25, broke Aaron Peirsol's world record in the 100-meter backstroke. He also won the gold in both the 100 and 200-meter backstroke races, and hasn't looked back since, consistently placing first in all major events.

Gianluca Urlando

Race to watch: 200-meter butterfly

In 2019, Urlando broke Michael Phelps' 16-year-old national age group record in the 200-meter butterfly, becoming an immediate frontrunner to make the cut in the 2020 trials. A shoulder injury in January 2020 looked like it might derail his plans, but now, with an extra year to recover due to the delayed Olympics, he is back on track.

Urlando, 19, is coming off a successful freshman season at the University of Georgia, where he won the SEC Championship in 200-meter butterfly and earned first team All-American citations in 100-meter and 200-meter butterfly.