I did my fair share of aqua jogging a few months ago, as I came down with some shin splints. From the research I did on the 'net, I found that aqua jogging time does not equal running on land time. I read that you need about 3x as long in the pool to get a “similar” workout.
That said, I assume you’re jogging in the deep end? With or without a floatation belt? You don’t necessarily have to cover distance in the pool. I did most of my jogging making a small circle in the deep end.
I used a belt the first time, and that was the last time. It depends on your body composition whether or not you really NEED the belt, but I found that the workout was much more intense without it. At first, without the belt, I thought there was no way I’d last 5 minutes. But I quickly built up to a 2hr “long run,” sans belt–talk about BORING.
How effective is it? It can be very effective. Being a research scientist, I couldn’t help but dig into the scientific journals. I found several scientific articles (not websites, but the source articles) about aqua jogging. Without remembering the details, I can tell you that those athletes who aqua jogged to try to maintain fitness were able to do so, while other experimental groups ran and rode bicycles.
As far as form in the water goes, I found myself taking slower, longer ‘strides’ for most of my runs. When doing intervals or quick runs, I have a much faster turnover. My stride would look like I was climbing stairs under water…rapid knee pumping, up and down like a piston.
So, if you don’t feel any resistance, likely you’re going TOO slow and too easy. It’s hard to get your HR up in the pool. That’s one thing I quickly found out about aqua jogging–that you can definitely lolly-gag around and not feel anything. So no, I wouldn’t say it’s normal for it to feel that easy.
Try some intervals, ladders, etc. 1 min hard, 1 min easy, 2 min hard, 2 min easy, etc etc. Those should definitely get your heart pumping and maybe some feeling in your legs, especially your quads. Let me know if you have any other questions…hope this helps…GOOD LUCK!