Theoretically, if more people are exercise and engage in weight training, then there should be some sort of decrease in the number of people who are suffering the effects of a lack of physical activity. While statistics show that more people are into fitness, the number of reported cases of diabetes and obesity are still on the rise. In adults, heart disease is also starting to become more and more prevalent, despite the fact that exercise is supposed to help reduce the risks of such problems. This presents an interesting question with a number of possible answers, none of which are particularly pleasant.
The first possible answer is that the people who answered the exercise question did not answer honestly. That would imply that while people are aware of the benefits and that they should engage in regular exercise, they simply don't care enough about it to actually do so. Either that, or the mental health mechanism known as denial is helping them associate common activities, such as raking the leaves or mowing the lawn, as exercise. This, in theory, is not entirely false, but it does not help reduce problems caused by another potential factor in the disparity of the statistical evidence.
Another possibility is that, even if exercise and muscle fitness numbers are on the increase, people aren't paying enough attention to their diet. It doesn't particularly matter even if you're exercising several hours a day and are lifting enough weights to put Arnold Schwarzenegger to shame, so long as your diet is full of grease, fat, and cholesterol. People may pay more attention to their exercise programs, but as long as the necessary dietary changes are not made or even touched upon, then things like heart ailments, obesity, diabetes, and the like will still continue to rise. If this theory is correct, then people are focusing solely on exercise and may not be taking the whole picture into account. A case of seeing the tree, but not the forest, as it were.
The research divided their results along a variety of lines. The racial groups with the highest rates of physical activity daily were whites and blacks. The age bracket encompassing college students and young professionals showed the highest exercise rates when the results were categorized by age. However, researchers admitted that most respondents were not likely to accurately report just how much physical activity they engage in on a daily basis.