Let's start small.
How many pull-ups can you do consecutively?
One? Five? Twelve? Whatever the number, this next integer is sure to make your eyes bulge.
Mark Jordan of Corpus Christi, Texas, set a world record for pull-ups by completing 4,321 in one day. Oh, and he's 54 years old. View the video here >>
"This is about a message that it's important to be able to take care of your health in many ways, no matter what age you are," Jordan told a television station in Texas. "The benefits are something than can not only help you but allows you to be able to provide guidance and inspire others as well."
The 24-hour feat was actually done back on November 4, but the Guinness Book of World Records didn't confirm the accomplishment until Monday.
Caine Eckstein of Australia set the previous record of 4,210 in October, a month before it would be broken by Jordan.
It took Jordan one year to train, raising money for the charity HELP, the Hammons Education Leadership Program for at-risk youth.
He said he stopped at 4,321 because it would be an easy number to remember.