"Exercise doesn't stop obesity; US report finds it's all about dieting"
Think those people on Biggest Loser would lose the weight they do if they just dieted and didn't exercise? I don't think so!!! While I'm not a big fan of the show, it does point out one key thing about exercise: you have to be doing it at the right INTENSITY in order to lose weight. Sure, "physical activity rates" have gone up, but that basically means that more people are reaching the MINIMUM recommended amount of PA (150 mins/week of moderate intensity). That is NOT enough to lose weight, even though it's a good start.
If you want to see what it takes for SUCCESSFUL LOSERS, check out this on-going study of over 10,000+ successful losers and see what eating and exercise strategies they did to lose the weight and keep it off. When it comes to PA, they are doing a MINIMUM of 60 mins., daily, at moderate to high intensity!!! That's way more than the 30 mins 5xw/k amount that is recommended by the federal gov.
Bottomline: If you want to lose excess FAT, build/tone muscle and bone, and get fit and healthy, you have to do BOTH--eat healthy, do cardio a minimum of 50 mins, 5x/wk at moderate intensity (at least!), and strength training at least 2x/wk. (There are other factors that impact obesity--sleep deprivation, toxins, too much stress, and other factors that increase chronic inflammation and impact epigenetics, but this is the core foundation of weight loss.)