Pushing The Limits Of The Human Body

Humanity has toppled scores of world records over the past few decades, but how much more progress can we make?

We humans are programmed to grow stronger, faster, and smarter; to climb higher, live longer, and populate every last inch of real estate. We’ve toppled scores of world records over the past few decades, but how much more progress can we make? No matter how we enhance our natural capabilities, our potential is bound by certain scientific principles—laws of physics, biomechanics, and thermodynamics—that don’t yield to human ambition. We asked scientists to define where, exactly, those boundaries lie, and to provide some take-home tips that’ll help you stretch your own potential.

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_This article originally appeared in the September 2014 issue of _Popular Science.

weight illustration

Heaviest We Can Get: 1,400 Pounds

Yes, our waistlines are expanding, sometimes to alarming proportions. But very few of us will ever reach the estimated 1,400 pounds that Jon Brower Minnoch weighed in 1978 (an approximation because he couldn’t step on a scale). For most folks, the upper limit is far lower. “People can tolerate 5Gs of force before they pass out,” says Gregg Kai Nishi, a surgeon at the Khalili Center for Bariatric Care in Los Angeles. “That’s equivalent to weighing 750 pounds. Short of a few anomalies, you don’t see people survive past that.”Illustrations by Muti
run speed

Fastest We Can Run: 10.5 Meters Per Second

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti
Most Weight We Can Lift

Most Weight We Can Lift: 1,000 Pounds

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti
Hardest We Can Punch

Hardest We Can Punch: 4,741 Newtons

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti
Tallest We Can Grow

Tallest We Can Grow: 8 Feet 11.1 Inches

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti
Keenest Our Ears Can Hear

Keenest Our Ears Can Hear: 100,000 Hertz

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti
Most We Can Remember

Most We Can Remember: 1 Million Gigabytes

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti
Smartest We Can Get

Smartest We Can Get: IQ of 198

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti
Most Colors Our Eyes Can See

Most Colors Our Eyes Can See: 1 Million

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti
Most Friends We Can Have

Most Friends We Can Have: 150 Friends

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti
Longest We Can Go Without Food

Longest We Can Go Without Food: 382 Days

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti
Deepest We Can Dive

Deepest We Can Dive: 214 Meters

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti
Highest We Can Climb Without Extra Oxygen

Highest We Can Climb Without Extra Oxygen: 29,029 Feet

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti
Longest We Can Go Without Sleep

Longest We Can Go Without Sleep: 11 Days

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti
Oldest We Can Live

Oldest We Can Live: 122 Years

After Olympic sprinter Usain Bolt broke the 100-meter world record at the 2008 Olympics, Mark Denny, a biologist at Stanford University, wondered: Had “Lightning Bolt” sprinted as fast as a human can go? After analyzing records back to the 1920s, Denny predicts humans may one day cover 100m in only 9.48 seconds, or .10 seconds faster than Bolt’s current record of 9.58 seconds––a lot speedier in a sport where differences are measured by the 100th of a second. PRO TIPS: How To Improve Your Fitness Even when your brain says no way, there are tricks to coax your muscles into running faster and biking longer. Race Against A Worthy Rival In a 2012 study, English cyclists were told to pedal as fast as they could. Then they raced against a computerized competitor going one percent faster, and kept up. So it’s a good idea to train with someone better. Breathe Easy, Or Hard Tim Noakes at the University of Cape Town had runners take a maximal oxygen consumption test that started surprisingly tough and got easier. He found that oxygen levels actually don’t limit performance. Gargle Gatorade In a 2008 study, cyclists gargled sugar water and spat it out, tricking their brains into thinking they’d ingested carbs. Swilling drinks stimulates taste-bud receptors, boosting the metabolism.Illustrations by Muti