Inactivity and Metabolic Health V

It’s time for another installment in my Inactivity and Metabolic Health Series! For your consideration today is the small but interesting study from the Washington University School of Medicine in St. Louis, Missouri:

Improvement in Glucose Tolerance After 1 Wk of Exercise in Patients With Mild NIDDM

There were only 10 middle aged men in this study. While it’s true that studies this small can’t automatically be extrapolated to apply to everyone, what I’m trying to show people through this series is that each small study serves as a data point in a broader constellation of evidence. There is quite a vast body of evidence that inactivity is a primary driver of metabolic dysfunction, and even though no single study can ever be taken of irrefutable evidence of anything, when dozens, hundreds or even thousands of studies all show similar results across population groups, one must sit up and take notice. You can prove pretty much anything if a single study is your litmus test (broccoli will kill you! I saw a study!). What does the weight of evidence say, though?

On to the study. 7 of the men in this study had mild NIDDM (non-insulin dependant diabetes mellitus) and 3 had impaired glucose tolerance (ie, they hadn’t been diagnosed with NIDDM yet but had the precursors). They were instructed not to change their diets over the course of the study, and kept food logs that were analyzed by a dietician to ensure that study results weren’t confounded by diet changes. They were given an initial Oral Glucose Tolerance Test, a physical exam (including blood lipid panel), and a maximal treadmill exercise test before study onset to establish baseline values.

The subjects engaged in a 7 day exercise program consisting of 50-60 minutes on a treadmill or ergometer, working at 60-70% of their maximum heart rate. On the 8th day they were given a second OGTT and exam. On the 9th day they were given a second treadmill test.


VO2 max, body fat percentage and weight all remained unchanged after the 7-day exercise program, so those factors did not confound the results. There was a 36% decrease in plasma glucose, a 32% decrease in plasma insulin concentrations, and a 32% decrease in triglycerides.

What is notable here is that the subjects’ insulin response to a glucose load (from the OGTT) was significantly lower than it had been before the study. What this means: their bodies released less insulin in response to the same amount of sugar after exercising for 7 days. This is significant to the Great Sugar Narrative that holds that sugar is the driver of insulin production and release. Clearly exercise is a pertinent factor here that is ignored by the sugar-causes-diabetes contingent. Exercise can mitigate the insulin response to sugar.

Plasma glucose also decreased, even with a decreased insulin response, which indicates that the cells ability to respond to insulin also improved. From the study:

“The results of this study show that regularly performed vigorous exercise can result in a significant improvement in glucose tolerance in some patients with mild NIDDM. This improvement occurred despite a significantly smaller increase in plasma insulin levels. it appears that the improvement in glucose tolerance was due to a decrease in resistance to insulin.”

Also of note: triglycerides decreased 32% with no change in diet.

Bottom line: exercise reduces insulin response AND makes the body more sensitive to the action of insulin. Exercise does lots of other groovy things too.

Keep moving.

My Pissed Off Low-Carb Rant


I’m not a scientist, I’m a lowly little Personal Trainer and Massage Therapist. I don’t perform studies (other than my N of 1 ones), I don’t write research papers, I don’t have a degree in anything health related.

What I do do is read a lot. Blogs (I’ve got a few of them listed in my blogroll), news articles, and most importantly, science. I try to find and read as many sides of an issue as possible.

And one thing I have, that a lot of people don’t, is an ability to think critically.

There’s a Diet War going on out there. One faction would have you believe that primitive man spent most of his time lolling about the savannah, working on his tan, only getting up off his ass long enough to throw a spear at a passing buffalo, then sitting back down to gorge himself and get back to the serious business of lazing about. Sounds pretty idyllic. Sign me up! Oh yeah, and that buffalo was made out of bacon.

Building on this belief system, they argue that modern humans are therefore primed for a life of blogging and bacon eating. It’s the true path to optimal health! See, our bodies are made to sit and eat fat, so when we eat carbohydrates, everything goes haywire. Insulin resistance, diabetes, obesity, cancer, DEATH.

‘Course, there’s all that pesky scientific data that suggests that increasing physical activity improves metabolic function (don’t believe me? Google ‘exercise and insulin resistance’, or check out my pinterest board on the topic). How can that be, if the body’s natural state is lolling about the savannah? If our bodies are designed to sit, why would moving improve metabolic function?

Do you REALLY believe primitive man spent most of his time on his ass? I don’t, not for a minute. I believe primitive man spent most of his time on the move. I believe the human body’s natural state is one of almost constant motion. When we move, we metabolize carbohydrate just fine. In fact, science holds carbohydrate is the brain and muscles’ preferred fuel (yep, I’m aware of the studies that suggest otherwise. Guess what? So far, they’re outliers). ‘Course, if we’re not moving, carbs can cause problems. But is eliminating carbs the answer? Only if you believe our bodies are designed to sit all day. If you believe that our bodies are designed to move, then eliminating carbs is a band-aid. A band-aid that might allow you to sit on your ass a few more years before disease sets in, but that ultimately doesn’t address the CAUSE of the disease: exercise deficiency. That’s right folks, I’m calling it like I see it: Metabolic Dysfunction is a disease of exercise deficiency, not of carb intolerance.

“But modern lifestyles make adequate exercise nearly impossible!” they claim. Bullshit. I have kids, a job, a household to manage, and a social life, and I am able to include adequate exercise into my daily routine. I also manage to maintain a blog! Yes, you too can blog AND exercise.

“But only young people and endurance athletes can eat carbs safely!” they counter. Bullshit, again. I’m 40. I exercise 30 minutes a day on average.

“But…but…some of us are so damaged by obesity and the Standard American Diet that we simply can’t ever eat carbs again!”. Bullshit, times 3. I was obese for 3 decades. At 35, I had a whole laundry list of metabolic issues: PCOS, high blood pressure, blood sugar regulation control problems, low HDL, and obesity (not to mention depression, panic attacks, migraines, hair loss, cyctic breasts and acne and much, much more). I reversed it ALL while eating carbs.

Ask yourself: which is more likely the natural state of the human body:
a. sitting and eating only one or two macronutrients, to the exclusion of thousands of edible energy sources
b. moving and eating whatever is easiest to find (which, where I live, would be mostly plants, with some rodents, insects and perhaps an occasional bit of larger game thrown in to supplement)

I choose b, and live accordingly (minus the rodents and insects). And you’ve seen my pictures. I suspect I look a lot more like the mythical Grok(ette) than most basement dwelling, bacon eating bloggers.