What's it like to run on the Alter G?

When I posted about running on the Alter G, I got two questions:
1. What's it feel like to run on the Alter G? and
2. How does the Alter G compare to pool running?

Dolly asked the first question, and, lucky for her, she can imitate the effects at home. And so can you! All you need is:
- a pair of tight bike shorts
- a nylon rope
- the abandoned Golds Gym set from the garage
- a treadmill

Here's what you do: Put on the bike shorts. Hold the entire set of weights in your arms and start running on the treadmill. After about a mile or two, put the weights down and straddle the nylon rope. Start running, while simultaneously pulling upwards on both ends of the rope, until it almost cuts you in half. And that's what it feels like to run on the Alter G.

No, but for real. If you are at a light enough percent weight, you are being buoyed up quite a lot. And you're being buoyed up right there. Basically, once you zip your bike shorts into the Alter G harness, the treadmill calibrates to your weight. Then you set it to the percent body weight you want, and it creates positive air pressure to offset the gravity due to the reduced percent. In other words, if I want to run at 75% of my body weight, the gravitational force that the remaining 25% would incur is negated by air being blown upwards. And it can be forceful enough to blow you almost off the belt by your shorts. That can be, ahem, uncomfortable.

Otherwise, the Alter G feels much like you'd expect: it has the same treadmill feel of propulsion as a regular treadmill, but you can tell that there is less resistance. You feel lighter, and it's hard - at low weights - to actually get your heart rate up. In fact, me and my out-of-shapeness have been running at 8.5 to 9, and it feels like an easy jog. But that's only for 15 minutes, so maybe I'd be really struggling by 30. I did not notice that it in any way changed my stride or form, except as would be expected on a treadmill.

The only other consideration is that you are zipped in, and the whole get-up is a little awkward - you have the harness in the way when you run.

Next time I will get to question #2 - Alter G vs. pool running.