Discuss as:

Inside the 'Human Body'

Discovery Channel
Click for video: A scene from the first installment of the Discovery Channel's
"Human Body" series shows how bones and muscles work together for survival
during a tornado. Click on the image to watch a video clip.

Did you know that your bones are stronger, pound for pound, than concrete? Or that in an emergency, your muscles could be three times stronger than you think they are? "Human Body: Pushing the Limits," a TV series premiering Sunday on the Discovery Channel, delivers those insights and more by analyzing the extraordinary feats of ordinary people, with virtual X-ray vision.

"The concept for the series came from our desire to, if you will, bring to knowledge of the human body what 'Planet Earth' brings to the world around us," executive producer John Grassie told me today. "So in many respects, this is the 'Planet Earth' of the human body."

That's a pretty high bar to reach, considering how sumptuous the panoramic shots were in that earlier TV series. The scale is much different for "Human Body," which focuses on the capabilities inside our skin rather than the wonders of the world outside.

The first program focuses on the usually untapped strengths of our skeleton and muscles, as well as our cartilage and energy storage system. On one level, we're watching the kinds of survival stories you often see on "Dateline NBC": a man who survives being sucked up by a tornado and thrown back down to earth ... a mountain climber who tosses a 1,200-pound rock off his chest ... a police officer who outruns a firestorm ... a swimmer who loses 14 pounds as he crosses the English Channel.

What sets "Human Body" apart is the inside view: computer graphics that reveal the workings of our hinged ribcages, our triple-teaming muscle fibers, our stronger-than-steel bands of cartilage and a fat layer that stores up the energy we need to cope with a crisis.

""It's not a question of the series designed to be a cavalcade of disasters," Grassie said. "Rather, the series is designed to highlight a series of examples that point up our potential, and show how we draw on that potential to help us survive. ... It's something that has evolved over God knows how many centuries."

The under-the-skin views will be familiar to anyone who's gone to a "Body Worlds" exhibit - or, for that matter, has watched "CSI," "House" or other TV shows that zoom inside the body. Grassie said that "Human Body" aims to increase the scientific quotient - and decrease the icky-innards quotient.

"There are some people who just don't want to look," he said. "So what we wanted to do is to focus on process, function, and how to present it in a way that we felt would be intriguing and nonthreatening."

Shows of strength merely provide the opening theme for the four-hour series, which also touches upon brain power, sight and sensation. Two episodes premiere on Sunday, and the two others will roll out on March 9 - with frequent repeat broadcasts. Grassie said the shows may also be coming to a school near you, complete with lesson plans developed to complement the educational videos.

For Grassie, the bottom line is to give viewers an appreciation of the "true potential inside each of us." Although the feats depicted may seem superhuman, Grassie they are actually within the capability of most people when they're pushed to the limit (or when they're trained to the limit). Here are just some of the factoids presented during the series:

  • Two hundred muscles come into play when you walk, and you use 100 muscles when steering a car. Even lifting a cup of coffee exercises 70 muscles. Normally, your muscles use only a third of their fibers at a time. But in extreme situations, like lifting a half-ton rock to save your life, all those fibers come into play. (Don't try that at home.)
  • When a ballerina dances on the tips of her toes, the force on those toes is equivalent to having three elephants stacked on top of each other. The real trick behind en pointe training has to do with tolerating, and even blocking out, the pain of that exercise.
  • The bands of ligaments that wrap around your knee can bear 7 tons of weight before giving way.

"If people come away saying, 'Gee, I didn't know that,' we've accomplished our task," Grassie said.

Chances are you'll be saying that at least once while you're watching "Human Body."

For more of those "I-didn't-know-that" moments, check out Discovery.com's "Human Body Explorer," as well as msnbc.com's interactive roadmap for the human brain, a look at the biology of a heart attack, and a graphical guide to the molecular motors inside your cells.

Update for 12:15 a.m. March 1: Todd Schroeder, a biokinesiologist at the University of Southern California who appears on "Human Body," got back to me during the afternoon and said he's looking forward to seeing the show on Sunday.

"I'm hoping they sell it as showing that the body is an incredible machine, and there are many components that fit together, and if stimulated at the right time with the right mechanism, you can generate incredible feats of survival," he told me.

However, he added, there's a reason why those feats are usually once-in-a-lifetime experiences.

"The body could not withstand that on a day-to-day or repetitive basis," he observed. "It's not something that should happen on a regular basis."

For example, he's worked with lots of athletes who are looking for an extra edge in the muscle department.

"You have individuals who are skinny, and they want to put on muscle mass ... and they put on one pound of muscle mass," Schroeder said. "That translates into five pounds of force on the knee. For five more pounds of muscle, that's 25 more pounds of force. Over time, that can be detrimental in terms of breakdowns of the joints."

Another issue relates to a routine known as whole-body vibration, Schroeder noted. The technique involves standing on a vibrating plate and literally jiggling your way to better fitness. Schroeder said whole-body vibration started out as a way to stimulate bone growth, and lately it's been touted as a method for burning off fat and enhancing muscle tone. However, all that jiggling may not be good for you in the long run - as jackhammer operators can attest.

"It's a matter of finding out what level of whole-body vibration is appropriate," Schroeder said.

Ironically, Schroeder himself is now in a position that requires bone-growth stimulation. He told me that he got pretty banged up in a snowboard accident a few weeks ago, and now he has to get around on crutches.

In the TV show, the first survival story is about the guy who was knocked unconscious during a tornado, swept up by the twister and dropped back down without breaking a bone. Schroeder surmised that the guy in the tornado survived relatively unscathed because he went totally limp - but when Schroeder had his own accident, he couldn't take advantage of that trick.

"I didn't have time to react in that way," Schroeder said."I wish I had."