I read this study the other day which added to the bounty of evidence of how important walking is. It’s a small one, looking at only 10 patients, but it shows what many other studies have shown; that unless you’re moving regularly, that bout of more intense exercise doesn’t do all that much (it’s called “exercise resistance”). In the study, they looked at certain effects of exercise which normally occur the next day (higher fat oxidation, and reduced plasma triglyceride levels after eating a high fat meal). They found that two days of reduced steps (i.e under 5000/day) impaired fat oxidation and caused higher blood triglyceride levels after the meal. On the other hand 8500 steps/day allowed the improvements in fat metabolism that exercise is supposed to cause.
These findings have been replicated elsewhere. For example in this study, 4 days of sitting and no exercise was compared with 4 days of sitting with a 1 hour bout of treadmill running on the evening of the fourth day. The next morning, a “high fat/glucose tolerance test” was administered to see how the body handled fat and glucose after a meal. Exercise is supposed to improve the body’s ability to lower fat and sugar levels in the blood after a meal like this, but there was no difference. This again, suggested that sitting for most of the day (or walking less than 4000 steps) cancels the benefits that acute exercise is supposed to give you.
Whenever somebody asks me about optimal exercise regimens, I always say to start with a foundation of regular walking. Its the base of your “fitness pyramid”. It’s easy, *almost* anyone can do it, it has a multitude of health benefits in and of itself, and according to numerous studies, enhances the effects of more intense exercise bouts.