The Area’s First Anti-Gravity Treadmill

South Jersey offers a faster way to rehab

Try the AlterG at Moorestown Running Company.

Ever wonder what it feels like to walk on the Moon? Since that’s an experience most of us will never have (other than in our daydreams, sigh), the next best thing might be a session on the AlterG anti-gravity treadmill at the Moorestown Running Company (MRC).

Typically only found in some physical therapists’ offices and the homes and training centers of über-speedy elite-level runners thanks to their hefty price tags—MRC’s AlterG cost $29,000—anti-gravity treadmills are invaluable to anyone dealing with an injury who doesn’t want to, or can’t afford to, lose fitness by taking time off to let an injury heal. It features a pressurized enclosure surrounding the belt of the treadmill that, when engaged, lifts the user ever so slightly from the treadmill’s surface and reduces the impact forces involved in the pounding of one’s feet. (In other words, your feet still touch the ground, but your footsteps land more softly than usual.) A mere 25-minute drive from Center City, the MRC is the only running store anywhere even remotely near Philly with an anti-gravity treadmill.

Realizing what a rare treat it is to something like this available for public use in our area—and generally being game for any activity that makes me feel I have something in common with my running idols (I love you, Paula Radcliffe!)—I quickly booked an early-morning time slot with Ralph Harris, the MRC staffer overseeing the AlterG program.

The AlterG, which arrived at MRC in mid-February, is tucked away in a bright, windowed alcove at the back of the store, set apart from the main shopping area, with a flat-panel TV mounted on the wall in front of it. With a console of colorful buttons and flashing LED displays, the machine itself looks much like a standard treadmill, with one major difference. The belt of the treadmill is surrounded by a chamber that fills with pressurized air around you (you’re sealed into place via a pair of stretchy neoprene shorts whose waistband attaches to the opening of the air chamber); this chamber makes it possible to run at less than 100 percent of your total body weight, thus reducing the force with which your legs and feet pound the running surface—all of which makes for a more comfortable run.

The chamber fills with air at first to calibrate your weight, then a second time with greater pressure to start the workout. As I slowly increased the speed, Harris smiled and said, “It’s like running on the Moon.” And he was right—it felt exactly like I imagine bopping around the Moon’s surface would be. As you reduce the body-weight percentage, you feel yourself lifted gently from the treadmill surface, and although your feet continue to touch the ground as you run or walk, the difference in how your landing feels is instantly noticeable.

But is it still an effective workout?

Compared to running an equivalent pace outside or on a regular treadmill, running on the AlterG would produce “a slightly lower heart rate and probably wouldn’t burn calories as quickly,” says Harris. But, he adds, “The typical tendency for a healthy runner using it would be to run about 20 seconds per mile faster at the same effort, or heart rate, as they would outside.” In other words, it’s easy to run faster on the AlterG.

“For an average runner who isn’t injured but is serious about training, it would be beneficial to add mileage [on the AlterG] into their normal routine, instead of replacing runs with it,” Harris says. Even adding just one or two runs per week would help a runner use her running muscles more, but by eliminating the excess impact on her legs would safeguard against overuse injuries such as shin splints and stress fractures.

Though I walked in to my AlterG appointment with mild skepticism (Who’s going to pay money to use this? How is this machine a good investment for the MRC?), after trying it out I realize what a valuable resource it is: for competitive runners who are trying to work through an injury without falling off their training program; for overweight individuals who experience discomfort walking or running but want to get in shape (the treadmill can accommodate users weighing up to 400 pounds and with up to a 48-inch waist); and even for average runners like me, who periodically experience little twinges of pain and want to avoid a full-blown injury and expensive, time-consuming physical therapy.

Now, if I could just satisfy this hankering for astronaut ice cream …

Cost is $20 for 30 minutes or $35 for one hour; packages of four, 10 and 20 one-hour sessions are also available. To schedule a session or for more information, call 856-234-9371 or visit