When I finished my first half-marathon last month, I experienced what it felt like to run on the ground for two hours. But what is it like to run in a gravity-reduced vacuum? When AlterG offered me the chance to demo their new "anti-gravity" treadmill, I couldn't resist. I jumped in my car and headed over to the gym at UCSF, down in the Mission Bay neighborhood of San Francisco.
A physical therapist named Chris gave me a rubber tube to wear over my running clothes. It looked like a cross between a wetsuit, a tire, and a tutu, and it had a giant zipper going across the top. He told me to step up onto the ramp and then zipped me into the giant rubber veil that covered what otherwise looked like a pretty ordinary treadmill.
The AlterG is no ordinary treadmill, though. It is a super fancy, super-expensive treadmill that isolates the lower body in a vacuum and literally takes off percentages of your body weight using technology developed by NASA. It's meant to help disabled, overweight, and injured people get a solid cardio workout without putting a strain on their limbs, but at this particular gym anybody can sign up to buy time on the machine in 30-minute increments. The AlterG uses air pressure to create the sensation of lost weight — the machine can reduce your body weight by up to 80%, making you feel like you're floating, flying, or bouncing on clouds.
By pushing arrow buttons on the treadmill screen, I was able to change my body weight percentage — air would blow into the vacuum that surrounded my legs, and the tutu-wetsuit became tighter, essentially lifting my body off the ground and making my legs float backwards into a naturally wider gait. It gave me a wedgie, and I could feel my thighs sweating from the tight seal, but none of that mattered. This was so much more fun than normal running! I ran on the AlterG for about fifteen minutes, happily romping through the clouds at a 7.5 min/mile, a near-impossible feat for the ordinary me. I felt like a gazelle.
I didn't realize just how much fun I was having in 20% gravity until my time was up. Chris deflated the air around my legs, unzipped me from the machine, and asked me to step down. As I lugged my now-impossibly heavy legs down from the treadmill ramp, I realized just how heavy I really was. My legs felt like elephants, and my spirits sunk so low that I wondered if I was suffering from a temporary depression.
So why can't all of us work out like this all the time if it's better for our bodies and more fun than real running? Maybe because the thing costs $24,500. And before the new version, the M300, was introduced last Monday, its predecessor cost $75,000. The New York Knicks and J-Lo have been known to work out on the AlterG, but it's unlikely to end up in my fitness room (what fitness room?) anytime soon. Let's not forget, our basic Bowflex costs about a grand, and we can all run for free outdoors.
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Don't forget the swimming pool, which any decent gym has; cycling machines; and elliptical trainers, which reduce strain on the limbs--all excellent no-impact modes of exercise. This thing sounds like fun, but really impractical for just about any exerciser.
Was the lift provided by the higher preassure in the chamber or were you being held up by the rubber tube thing? Seems to me like you would need quite high preassure to cancel someone's weight out, especially if they're overweight. If it is the rubber tube thing providing the lift, why wouldn't you just put on a similar kind of harness around your waist and suspend yourself on a pair of adjustable rubber cords to the ceiling? Seems like pretty much the exact same thing, without the need for some sort of preassure chamber and completely sealed in legs.
Running is hell. That's the way it's supposed to be. Yeah, I'm old-school.
"...isolates the lower body in a vacuum..."
Sounds very, very painful. (Note to marketing dept: Promote this as effective for erectile dysfunction disorders.)
Given that a standard Precor treadmill costs around $5,000, and a Precor elliptical pushes $7,000, the $24,000 doesn't seem all that unreasonable. Not that I'm likely to be putting one in my house any time soon!
Oh, and I imagine that $24,000 wouldn't go far in installing an indoor pool, much less maintaining it... Gym equipment is expensive. Very, very expensive.
If I undeerstand this correctly, it has INCREASED pressure on your lower body, not a vacuum. Just look at the photo, the membrane is bowed OUT by pressure, not IN from a lack thereof.
I'm a little confused. You seem to say both that it's a vacuum, and that it's filled with air. The site doesn't help much either, giving no indication of how it works.
Another review seems to suggest that the bottom chamber is actually pressurized, though, not a vacuum, so I guess that explains how it makes you feel lighter. Does it not feel any harder trying to move through pressurized air, like running through water?
Since the mechanism that makes exercise beneficial is resistance to gravity, wouldn't it take many hours a week to stay in shape using this thing? The one nice thing about running is it doesn't take too much time to get your minimum recommended dose. (I agree, it is hell in all other respects.) But who would have time to use this for fitness on a regular basis.
Though it does sound like great fun, and I would love, love, love to try it.
Hi Lisa,
Thanks so much for checking out the AlterG Anti-Gravity Treadmill. I'm glad you had a fun time doing a "low gravity" workout. After reading the comments, I thought it might be helpful to point out a few more things and answer a couple of the questions posed.
First is that the AlterG is available to be used at a growing number of physical therapy clinics, so it is becoming increasingly accessible to the public. And more and more athletes and people rehabbing from injuries are using it on a regular basis, as a piece of gym equipment.
To respond to @unruly katy's notion that running is hell and it's supposed to be that way. The AlterG is not meant to replace your running regimen. If you are a runner, it can enhance your running regimen and help ensure that you can stay healthy. If you've ever had shin splints, stress fractures, plantar fascitis, sore knees or the myriad of other lower body injuries that running can cause, you'll know that you basically have to sit out for a while to heal, and then you have to get back in shape again. The AlterG can change that. America's best distance runners are using the AlterG to train through injuries and also prevent them by working out in lower gravities as a part of their new workout routine. People like Dathan Ritzenhein (who recently set the American 5K record) swear by the AlterG as a regular part of their regimen.
To answer @SamSam's question, the AlterG works by inflating the bag that surrounds your lower body creating air pressure that is higher inside the bag than outside. This positive air pressure literally floats you off the treadmill, creating a totally comfortable running or walking experience, where it feels just like a normal treadmill workout, only you are lighter. Sorry the site is not as informative as you would like, we're working on that. If you'd like to see a video of how the AlterG works, you can click on the Medical link on the top nav (from the home page) and watch the short video to see how it works.
I hope all that helps. And thanks again for trying out the AlterG!
Gabriel
AlterG
Maybe someone can answer this for me; why do joggers jog in the street? That just bugs me.
As opposed to? Running on the sidewalk? Around my house there are no sidewalks, but presuming that's what you meant sidewalks are often narrow enough that dealing with other pedestrians is somewhere between annoying and dangerous. As the runner the expectation is that you will yield to the pedestrians, dog walkers, baby strollers, etc. and jumping off the sidewalk to the grass strip constantly gets annoying and risks twisting an ankle on a tree root. Sidewalks are also often humpty-dumpty from tree roots and the like, roads tend to be smoother.
I don't have the sidewalk option so I run in the street, generally in the middle of the road since the streets here are heavily crowned and running in the gutters is like running along the side of a hill. I don't wear headphones so I can listen for cars and move out of the way when they're coming.
I run in the street instead of the sidewalk because in my neighborhood the streets are asphalt and the sidewalks are concrete. Asphalt is WAY easier on your body than concrete.
Isn't that going to get all nasty with sweat?
Give running on a sidewalk a shot, and you'll see why few runners do it. Do it right. Run five or six miles. I doubt you'll wonder after that. I can usually run a mile or two on a sidewalk. Three or four, and I WILL trip, catching my toe on a seam.
--Beryl
We have these reduced-gravity exercise machines now, they're called swimming pools.
Why not create the same reduced gravity effect by creating a frame above the runner that holds them in a full torso harness, thus taking some stress off the waist and crotch and putting a little of it under the arms also? They make set ups like that for babies called "baby jumpers" that you mount in your doorway and has springs. They also make set ups like that with bungie cords for trampolines so you can flip and bounce suspended slightly.
It's surprisingly simple physics that makes this work. Think "kayak skirt" Lisa describes as a wetsuit tutu. There's nothing through the crotch. It all works by air pressure across what is effectively the cross section of your waist. A decently fit person will have a cross-sectional area of about 70 square inches, so it only takes a couple of PSI (15 kPa) of excess pressure to take your entire weight off (apologies to 95% of the world's population for using such archaic units). Heavier people with larger waists have more area too, so it all works out). NASA used it to pull negative pressure, and increase your apparent weight, to use a treadmill in zero G. (disclaimer: I worked with the NASA team that first did this for the zero-G treadmill, but I didn't work on that actual project. We then used it to study body response to blood pressure changes, since it also does a great job shifting blood volume in and out of your lower body.)
I'd rather use a machine that INCREASES gravity. That way, I would feel like I'm running in the clouds the rest of the day instead. Of course, that machine is called an ankle weight.
The physics may be simple but so is the similar physics of an adjustable neoprene harness that suspends the treadmill runner from above and achieves the same effect at a fraction of the cost. And it would be much quieter. Rather than squeezing someone around their waist with air pressure and PUSHING them up, you could squeeze them around their waist with a velcro adjusted neoprene waistband and PULL them up with cordage attached to springs attached to a hook in the ceiling. Then you could use it with your existing treadmill.
About the idea of suspension from above rather than from below... there is a company that makes such a "baby-jumper" style harness and treadmill called Kaye Suspension Walkers. They sell the harness separately also.
Someone patented a similar idea to grab a bicycle rider around the waist and suspend them slightly above the bike seat, thus eliminating the pressure against the bike seat.
The ULTIMATE variation of this idea of "running while suspended" was created by a guy who suspended himself from a custom made bicycle that has no seat, but instead has a frame that goes over his head that holds a harness that suspends him. That way, he can actually run on the street while being suspended in the air! He calls it GlideCycle.
Nice to see the marketing guy knows his stuff. Too bad Alter-G can't prove anything they claim. Their "clinical research" are actually case studies from PT's. Not MD's, not IRB studies. They've been around since 2005 and no real science. They are claiming medical benefits. Let me quote a couple from their own web site
1. Neuromuscular and proprioceptive re-training. Newton or common sense cover that?
2. Lowers the risk of falling. Really? Any studies to support that claim?
3. Improves neuromuscular control and activity and promotes brain plasticity. I don’t see any studies on this claim either.
Alter-G should prove their claims or stop making them.