7 Women Who Set World Records

It's one thing to be the first woman to break a record. It's another to be the first person. In both sports and American history, record-breakers are segregated by sex. Sometimes it's a product of physiology, other times it's just good old-fashioned backwards thinking. Nobody believed a woman could break a man's long-distance swimming record, or that anyone would dare to try. But in 1926, a 19-year-old named Gertrude Ederle knocked down every roadblock when she swam 35 miles across the English Channel, breaking the men's world record by almost two whole hours. Today, women are defying categories with the speed of an Olympic sprinter. In honor of Women's History month, here's a look at some recent record-breakers beating men to the finish line.

PHOTOS: 7 amazing, world record-breaking women

Most Twitter followers: Lady Gaga

Lat week, Gaga became the first person with 20 million Twitter followers. She's already been the most-followed person in the world since 2010, so she was only competing with herself. Justin Bieber came in a distant second with 18 million followers. But Twitter is a woman's world: Katy Perry, Shakira and Rihanna rounded out the top five list of most-followed.

Longest distance on treadmill: Sharon Gayter
In 2011, Gayter jogged 517.33 miles in 7 days, breaking the men's and women's world record, and possibly, the treadmill she was running on. The previous record was made by Lee Chamberlain who ran 468.04 miles in 2009. Several scientific studies have suggested that while men are faster long distance runners, women have more endurance, possibly an outgrowth of centuries of marathon labor pains. But stamina isn't just inherited, it's developed. On March 25, Gaytor will run 350 miles in less than five days from the southern tip of Ireland to the northern most point to break yet another distance record.

Longest distance solo swim: Penny Palfrey

Last year, the 48-year old grandmother broke the world record for the longest solo unassisted swim. Her 68-mile crawl across the Cayman Islands in nothing but goggles and a swimsuit involved reckoning with sharks, unpredictable currents and paralyzing jellyfish to make it to finish line.

Related: Penny Palfrey's record-breaking swim

First person to break a world record in London's new Olympic pool: Ellie Simmonds
The Paralympic champion swimmer pulled a double whammy this past week when she broke 200 meter medley record in a little over 3 minutes, beating her own personal best time by a second. She also became the first person to break a single record in the newly minted massive pool the world will be watching come July's Olympic games.

Fastest Appalachian trail hiker: Jennifer Pharr Davis
Davis had already conquered the 2,175 backwoods trail from Maine to Georgia twice before; but in the summer of 2011, she did it faster than anyone else. The 28-year old hiked up to 47 miles for 16 hours a day in order to complete the trail in just under 47 days, and break former champ Andrew Thompson's 2005 record.

Biggest worldwide jumping jacks organizer: Michelle Obama (and 300,264 other people)
Last year, the First Lady promoted her "Let's Move" health initiative by assembling a team of 400 kids at the White House and a host of other organized events around the country to break the world record for the most people doing jumping jacks in a 24 hour period. Her plan worked, and the old record, of 20,000 jumpers became yesterday's news.

Watch: Michelle Obama helps set new world record

Most Academy Award nominations: Meryl Streep. This year's best actress Oscar winner has been nominated more than any other actor on the planet. With 17 nods, she leaves runner up Jack Nicholson's 12 nominations in the dust. Not that we're counting.

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