Friday, December 5, 2008

Evidence vs. Belief: A Nice Long Rant

Yesterday's WOD:

3 rounds for time of:

30 sit-ups (unanchored)
113# deadlift 15 reps
row 500 m

My time was 18-something. Those deadlifts were heavy! I tried 123 and got it, but I didn't think I could get 45 reps. I wonder what my 1 rep max is on deadlift now. Last time I did it was right after I started at FCF and I got 128. I bet I could get more than body weight now.

Today is Friday, which means it's Mike Hat Eye Candy Friday:

80/20 cotton/wool, fold-up 2x2 ribbed brim, standard decrease. This was a 2nd anniversary present (hence the cotton).

I have a nice long rant for today. Enjoy.

I have a completely different understanding of fitness and health than I did just 3 months ago. I see now that the conventional wisdom about health and fitness, or "Today Show advice" as I like to think of it, is just plain wrong, and I am mad that people don't get it.

Why don't they get it? Why do they continue to believe so-called experts when the data do not back them up? Low fat diets do NOT increase longevity or help people lose weight, low-intensity exercise does NOT improve metabolism, shortcuts and fads do NOT work over the long term. As a scientist, I am convinced by logic, plausible mechanisms, and the data to back them up. I sometimes forget that people not trained in the scientific method think about the world very differently.

This article is an example of reasoning that makes scientists shake their heads and feel very uneasy. I want to start by saying that I have met the author, she is a very nice and intelligent person, and this is in no way a personal attack on her. I'm just trying to use the article she wrote as example of non-scientific reasoning, examine the logic that is there, and provide an alternate, more scientific way of looking at the issue. I also want to say that it was very brave of her to publicly disclose struggles with anxiety. I recognize that this is a real medical issue that many people struggle with and I am not trying to trivialize it in any way.

The premise of the article is that by getting piercings at certain "pressure points" (that are allegedly important locations in acupuncture), the qi (or life force) is changed in some way, which affects psychological health directly (i.e., reduces anxiety). The anecdotal evidence was that the author got a piercing at what is believed by acupuncturists to be anxiety-related pressure point, and she stopped having anxiety attacks.

You have 2 events, piercing and cessation of anxiety attacks. These two events were correlated, not necessarily causally related. All we know is that they both happened around the same time, so all we can say for sure is that they co-occurred. Let's examine a couple of other possible explanations for why these 2 events co-occurred.

1. Coincidence. Sometimes 2 things happened around the same time, and they are unrelated. Maybe the author got better for other reasons - maybe things were going well at work or she had increased social support or her physical health improved, and she just happened to get a piercing at that time. Coincidences happen all the time.

2. Placebo effect. Although she didn't reflect on it consciously at the time, it's entirely possible that, at a subconscious level, the author felt that the piercing was helpful or cathartic. The placebo effect (believing that something works makes it work) is a very powerful effect that is easy to underestimate.

3. Pain triggers psychological responses or distracts you. Maybe the pain or other physical sensations of the piercing triggered a psychological response of some kind. It is certainly conceivable that a physical sensation could either trigger or blunt emotions, or at the least, provide a distraction from the anxiety.

4. An interaction. An interaction is basically when a simple cause-effect story gets more complicated when you add in another factor. Say that certain psychological tendencies plus environmental stressors lead to anxiety attacks. That is the simple story. It gets more complicated when you add in another factor: choosing to engage in the somewhat counter-culture behavior of getting a body piercing. This other factor intervenes in the simple story, reducing the anxiety, perhaps because the anxious person feels they are doing something constructive in going against the mainstream and they get a greater sense of control which helps them counter the anxiety.

If you start using your imagination, you can come up with lots of explanations, none of which require divine intervention, a life force, or any of that nonsense. Of course, that doesn't prove those explanations wrong. But if there is a simple, logical explanation that does not require intricate belief structures for which there is no scientific evidence, doesn't it make sense to go with the simple, logical explanation?

Now to get back to how this relates to CrossFit. The acupuncture-piercing story that the author of the above article tells is a belief-based explanation. It only holds together if that belief system holds together. It seems odd to a scientist because scientists use evidence-based explanations, not belief-based explanations. CrossFit is evidence-based fitness. However, the "Today Show advice" approach to is belief-based. I believe that fat is bad because that is what people have told me, I believe that an hour walking on the treadmill is good for me, etc.

Why does most of the medical community side with the belief-based approach? Aren't doctors scientists? Nope. Most doctors are practitioners, not researchers. They are highly skilled technicians. (The people making medical breakthroughs, finding cures, improving treatments - they are researchers who are sometimes also doctors, but when you go to the doctor's office, chances are you NOT seeing a researcher.)

So I think that the persistence of wrong ideas about fitness and health, and the accompanying resistance to evidence-based approaches like CrossFit, results from a reliance on belief-based explanations that permeates our medical system and our society in general.

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