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Getting in Touch with Your Motions

Ahtletes worth their joint receptors learn to move with a sense of kinesthetic grace
By Mark Jannot

Quick: Where is your right index finger–exactly? At what angle is your left elbow bent? Now touch your toes. Jump up and click your heels. Lean your head back, arms outstretched, and touch the tip of your nose with each middle finger. Now do it all over again, but with your eyes closed.

What you’ve just completed is a basic bit of kinesthetic calisthenics. Kinesthetic awareness–the ability to know where your body parts are in space without seeing them–is a crucial component of almost any movement you’re likely to attempt. Stripped of such awareness, you couldn’t inch your way toward empty seats in a dark theater or grab a box from an overhead shelf. You’d
also be hopelessly lost in a kayak.

“Kinesthetic sense is the cat that you throw out of the barn that lands on its feet every time,” says Fritz Hagerman, an exercise physiologist at Ohio University in Athens. “Every athlete exhibits kinesthetic sense, but it’s more evident in those who perform highly ballistic stunts. Divers and gymnasts, for instance, are actually judged on that basis–on how they land.”

Style points aside, our ability to succeed at our own ballistic stunts–such as descending whitewater, single track, or a field of moguls–as well as less projectilelike but no less complex activities like rock climbing and rowing–has everything to do with how well we control our many body parts, not all of which we can simultaneously keep an eye on. This usually isn’t a
problem for a task we’ve done over and over. But when we want to raise our game or try a new sport, it’s seemingly impossible to keep track of what goes where. It’s as if our kinesthetic sense has abandoned us.

Keep Tabs on Your Golgi Organs
Being kinesthetically aware starts with the proprioceptors, the end agents of the nervous system’s kinesthetic network. (The prefix proprio- signifies that these structures respond to stimuli that are received from within rather than from outside the body.) Three crucial types of proprioceptors feed information to the brain: joint receptors, nerve
endings that line the joints and are switched on and off in sequence as the angle of the joint changes; muscle spindles, tiny capsules of muscle fibers and nerves embedded in bigger muscles, which react to those muscles being stretched or contracted; and Golgi tendon organs, found near the junction between muscles and tendons, which pick up the larger forces at play on the
muscles, such as resistance or strain from meeting a solid object. With every move you make, proprioceptors send information to the cerebellum, the part of the brain where information on thousands upon thousands of previous muscular motions has already been stored. That stored info is then used for reference.

How this arrangement works to create kinesthetic awareness is illustrated by an exercise that nobody wants to perform: the fingertip-to-nose sobriety test. “When you think about it, that’s a pretty complex task,” says Gary Kamen, a motor-control expert at Boston University. “Your eyes are closed, but you need to know where your finger and nose are in space.” Kamen says that as
you start the motion, the proprioceptors begin feeding data to the cerebellum. “And if there’s a mismatch between current information coming in from the joint receptors and muscle spindles and the information that’s stored in the cerebellum,” he says, “the cerebellum says, ‘Uh-oh.'” It then sends a signal to fire up or turn off another group of proprioceptors, modifying the
trajectory of the arm or the finger until–with the help of your Golgi organs–you realize that a successful landing has been made. Why is this drill so popular at the highway patrol? The neural pathway between the proprioceptors and the cerebellum is among the first things to be impaired by alcohol.

Practice
The frustrating part about all of this is that while scientists understand exactly how kinesthetic awareness works, they have little idea why one person’s system functions better than another’s. The best answer they can muster is that genetically speaking, we weren’t all born Oksana Baiul. “I’ve worked for years with elite rowers, professional baseball players, and race car
drivers, and it’s clear that exposure to a sport early on is an important factor,” says exercise physiologist Hagerman. “But genetic quality far outweighs everything else.”

Even if you weren’t born with grace and fluidity in your every motion, however, you can teach an old cerebellum new tricks. There’s plenty of room to improve within the limits set by your genes. The mantra for kinesthetic improvement is practice, practice, practice. “The idea is to rehearse the coordination so much that it becomes second nature,” says Hagerman. “I heard a good
teacher once say that the best athlete could function with his head cut off. Don’t let conscious activity get in the way.”

The idea that you should practice is hardly surprising. The idea that you should practice blindfolded, as Kamen suggests, shouldn’t be surprising either, considering what you’re trying to learn. He cites a study from the 1920s in which neophyte basketball players were each given a hundred shots from the free-throw line–but half were blindfolded and told where each shot landed.
Then the blindfolds were taken off, and everyone was given ten more shots. Who do you think made the most baskets? Not necessarily those with the athletically privileged genes. “Invariably, when you provided vision to the group that had practiced without it, their learning curve was steeper and faster,” says Kamen.

Alison Sheets, director of the Winter Park Blind Rock Climbing Program in Colorado, occasionally climbs blindfolded to enhance her own kinesthetic sense. “It gives me a little more understanding of how extreme the forces of gravity are,” she says. “A three-inch step can feel like a yawning abyss. Blindfolded, you’re so focused on how you move and what you can feel that you’ll
happily use a nearby one-inch hold when a two-inch hold is next to it. With vision you keep awkwardly working on getting to that two-inch hold, even if it’s out of reach.”

For those who are still skeptical of the no-vision method–or who aren’t ready to rope up with their eyes closed–a good, safe testing ground may be your neighborhood bowling alley. Kamen conjured up what he calls phantom bowling while in grad school. “I was asked to teach bowling, and on the first day I said to the attendant, ‘We’d like to bowl without any of the pins.’ He
looked at me like I was pretty stupid, but he did as I asked.” Kamen’s students progressed rapidly, smoothing over the flaws in their motions, but he said he could have gone farther still–he wanted to take the ball away, too. “But I didn’t,” he says. “At some point you’ve got to compromise to maintain interest in the activity.”

Mark Jannot, a frequent contributor to ���ϳԹ���’s Bodywork pages, wrote about open-water swimming in the August issue.