Yes, water provides more resistance. And provides you with greater support and lower impact. The two kinda offset each other. Estimates on whether it burns more or less differ depending on the exercise. For most exercises, it's less. The increased resistance is offset by your reduced weight and strain. you're not fighting against exercise. You move at a slower pace, against increased resistance... instead of a faster pace. It's just different! Basically, while you do burn more calories than a similar activity at the same pace, you can't move as fast as you would on land. I could probably burn more calories water walking at 2 MPH than I could walking at 2 MPH on land... but I can go up to 7 MPH on land. :) So overall, I will burn more calories on land.
Zumba, for example, is a very high-impact, high-energy activity. Much of its calorie burn comes from that high impact. In general, low impact exercise will not burn as much as low impact. It's the speed and impact that give zumba it's high calorie burn... by definition, you will be moving slower in the water.
Some examples: www.nutristrategy.com/activitylist4.htm
Strength training doesn't burn a lot of calories. :) I'm sorry, but it doesn't. It does result in added benefits like increased calorie burn at rest, etc, but the act of lifting weights is an anaerobic exercise. It's not the same as cardio; Cardio generally burns more calories overall. :) www.sparkpeople.com/community/ask_the_expe
The benefits of strength training are vastly superior to that of just cardio alone; don't get me wrong. I LOVE strength training, and feel it should be the focus of any routine. It is just not a big calorie burner, though. The muscles don't use energy the same way, and the relationship between heart rate and energy use is not the same, either.
And I'm also not saying that water aerobics isn't a great form of exercise; it really comes down to whether or not you enjoy and will do it. You will not be able to get an accurate guess; Water Zumba hasn't been studied the way most stuff has. It's best to go with the generic "water aerobics entry" because you're going to underestimate, if anything. There's no way you'll be able to guess at the actual burn.
Either way, this is not my specialty. Others who are more knowledgeable than me will have to explain it better. :)
Edited by: DRAGONCHILDE at: 8/6/2012 (18:08)