It has long been known that exercise can help curb your hunger and make better food choices. But it has to be the right type of exercise.
I’ve been critical of the current recommendation to exercise 30 minutes per day. The American Heart Association gives these recommendations:
- At least 150 minutes per week of moderate exercise or
- 75 minutes per week of vigorous exercise (or a combination of moderate and vigorous activity).
- 30 minutes a day, five times a week is an easy goal to remember.
The principle recommendation is always to start with walking.
Now, I would never tell someone who has chosen to walk around the block for his or her exercise to hang it all up and go back and sit on the couch. But, given how poorly we are managing our chronic disease risk (namely obesity, diabetes and heart disease) we have to admit that these recommendations just are not the right ones.
Given the research on short-burst aerobic activity and the benefits over traditional aerobic programs, you need to start moving in this direction. If you’re serious about getting and staying healthy, you need to stop the status quo and get serious about your exercise routine.
By making it shorter.
Yup. I firmly believe we are wasting our time with the exercise we are doing. It’s not intense enough. There is something about hitting the anaerobic zone—the point where your body runs out of oxygen for ATP formation and switches to glycogen burning—that triggers a wakeup call at the cellular level. The cellular equivalent of the “fecal matter hitting the fan.” Our cells become more efficient at utilizing energy and this means all kinds of good things for our bodies.
As an example, we just got a brand new treadmill. I’m normally an elliptical-type person, but I thought I’d give it a whirl. Took me a few times to get it down, but I’m running at a 10 degree incline at 8 MPH in 30 second bursts. Currently doing 10 sets, although this may change depending upon how good the movie I’m currently watching on Netflix is…
My heart is hammering at the end of the 30 seconds and it takes about 1-2 minutes for my heart rate to calm back down, at which point I repeat the 30 second burst. Ultimately I’m running 5 minutes total at a pretty hard pace (for me anyway). By the end of my short workout, I really feel like I’ve done quite a bit of work.
THIS is what I recommend to all of my patients. Running, exercise bike, elliptical, swimming, jump roping, rowing—this approach is versatile enough to work with all of these. Incidentally, I firmly consider weight training to be short-burst aerobic, since it is usually lack of breath that keeps you from jumping right up to the next barbell.
All of this goes back to this particular study. In it, researchers looked at the effect of more intense aerobic activity (60-minutes running at 70% maximum aerobic capacity—not my short-burst, but you still get the idea that this is NOT walking around the block). Specifically, researchers looked at how exercise affected the desire for high calorie versus low calorie food. Here are the specifics:
- Participants were evaluated under functional MRI, looking for blood flow in the brain.
- Exercise increased thirst as well as core-body temperature.
- Lowered ghrelin concentrations and upped peptide YY release (essentially shutting down hunger).
- With exercise, images of high-calorie foods increased blood flow to regions of the brain that lead to better decisions (dorsolateral prefrontal cortex) and lowered blood flow to regions of the brain that associate food and rewards (orbitofrontal cortex).
- With exercise, low-calorie food images increased blood flow to reward areas of the brain (insula and putamen).
Overall, it is clear that exercise directly acts on the brain to affect your food decisions, leaving you with better choices. This explains why sitting on the couch is directly related to the intake of beer and potato chips.