2012 Olympic Swimming: US Stars Dana Vollmer, Elizabeth Beisel Set Records

Two of Team USA's best swimmers—Dana Vollmer and Elizabeth Beisel—made an early statement at the 2012 Summer Olympics.

Vollmer set an Olympic record in the 100-meter butterfly with a time of 56.25 seconds, and Beisel came just 2.23 seconds away from a world record.

With a time of 4:31.68 seconds, Beisel swam the fastest qualifying time in the women's 400-meter individual medley. She also set the "textile" world record, meaning she's the fastest of all time outside of those marks set during the sport's short-lived synthetic-swimsuit era of a few years ago.

Let's take a look at what to expect from each Olympian in the next round and their toughest competition.

Dana Vollmer, 100-Meter Butterfly

Vollmer was the only Olympian to break the 57-second mark in the women's qualifying of the 100 butterfly.

Her time is just 0.19 seconds off the world record set by Sarah Sjostrom of Sweden and creates much momentum heading into the semifinals. Vollmer hasn't competed in the Summer Games since Athens in 2004, and there she didn't race the 100 butterfly.

If anything, Vollmer's preliminary performance is most impressive because she simply continues to improve. Considering that the 4x200-meter freestyle relay is her only other event, Vollmer is clearly taking the 100 butterfly to heart.

She failed to medal in the 200 freestyle in 2004, so there's added motivation to slice water this time around. Now Sjostrom is among the competition that qualified as well, so the pressure is on Vollmer to remain the front-runner.

That said, she's arguably been the most consistent in the 100 butterfly since 2010, which is to Vollmer's advantage in confidence.

Elizabeth Beisel, 400-Meter Individual Medley

Beisel is so close to the world record she can almost taste it, and that was without a synthetic swimsuit, which were banned in 2010, as noted by Kristina Wong of ABC News:

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Beginning this year [2010], swimmers are banned worldwide from wearing polyurethane and neoprene suits during competition.

FINA, the world governing body of swimming, issued the regulations earlier this year after an unprecedented number of swimmers broke world records after the high-performance swimsuits were introduced in 2008. The regulations went into effect Jan. 1, 2010.

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Beisel not only led qualifying for the women's 400 individual medley but also finished far ahead of Australia's Stephanie Rice, the world record-holder.

Based on her qualification performance, Beisel is quite hungry to win. She just missed a medal in the 400 medley in Beijing after taking fourth, so the motivation to go all out is beyond evident. The gold medal is Beisel's to take; now she simply has to go in the pool and get it done.

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