The New York Times has a blog talking about how being inactive for some hours per day increases your risk of heart disease, even if you exercise. References a study. Unfortunately, the study comes to different conclusions; from a commenter on the blog:
From the abstract of the actual study:CONCLUSION: In addition, high levels of physical activity were related to notably lower rates of CVD death even in the presence of high levels of sedentary behavior.
From the article:Their workouts did not counteract the ill effects of sitting.
This is ludicrous and embarrassing. Remind me not to read this sort of garbage in the future.