There's definitely been progress. I've seen mentions of interval training in many mainstream magazines. Even an article in the recent issue of Prevention mentioned how many women complained of not losing weight on their walking problem. No surprise to me; check out Walking Is Great Exercise - Another Myth Exploded
So, there has been progress but not enough. I still see way too many Twitter and Facebook comments about doing cardio to lose weight. Even some gym members have convinced themselves that cardio is the key.
Sorry, the research just doesn't back that up. It doesn't matter that you sweat more doing the elliptical than when you're strength training or that your heart rate is higher running on the treadmill. Those activities will not help you discard unwanted pounds better than resistance training.
Intervals are definitely better than steady state cardio but even intervals are not the best type of exercise to get rid of excess pounds and inches.
I've posted a link to the article below before but it obviously needs to be posted again. It's long but it's worth it. Print it out and read it when you really have time to absorb the information.
It's written by Alwyn Cosgrove, a highly respected trainer and fitness author. His methods are based on studying the research and years of results with real world clients.
Even though Alwyn was involved himself in MMA and has trained many athletes, the vast majority of his clients come to lose fat. By his own admission, he has "made more money from the fat loss market than any other single client group." Alwyn's (and wife Rachel's) Results Fitness gym was listed as one of Men Health's 10 Best Gyms in America. This guy knows his stuff. If you're silly enough not to believe me, that's one thing ;-) but give this guy a serious read.
Here's a short excerpt but don't get scared off, the entire article is not full of research jargon...
Both groups lost weight. The resistance training group lost significantly more fat and didn’t lose any LBM, even at only 800 calories per day. (The reason the calories were so low was to really take any dietary variables completely out of the equation and compare the effects of the exercise regime on LBM and metabolism.)
** Mickey's note: In case you didn't figure it out, LBM = lean body mass. **
The resistance training group actually increased metabolism compared to the aerobic group, which decreased metabolism. It seems that resistance training is a more significant stress to the body than a starvation diet.
In my experience, full body training in a superset, tri-set, or circuit format (with non-competing exercises) in a rep range that generates lactic acid (and pushes the lactic acid threshold or LAT) seems to create the biggest metabolic demand. It makes sense: training legs, back, and chest will burn more calories and elevate metabolism more than an isolated approach training one of them.
If you are interested in slimming down, do yourself a favor and read the entire article here. The Hierarchy of Fat Loss It tells you the most effective type of exercise to do depending on how much time you have to spend per week.