Monday, October 4, 2010

The Bear and why you shouldn't wear sunscreen

My attempt at explaining The Bear to Corey on the whiteboard on our office. Yeah, it's just that awesome sharing an office with me.

Today's WOD: The Bear

7 cycles of:

1 power clean
1 front squat
1 push press
1 back squat
1 push press

5 rounds of the 7 cycles adding weight each round. Rest as needed. You cannot put the bar down during the cycle.


Finally got 70#! Woo hoo! I was wondering how many times I've done this terrible WOD, so I went through my archives.
  1. 28-33-38-38-43 November 12, 2008
  2. 38-48-53-53-53 January 27, 2009
  3. 48-53-58-58-58 March 26, 2009
  4. 45-55-60-65-XX October 5, 2009
  5. 45-55-60-65-XX March 10, 2010
  6. 45-55-60-65-70 October 4, 2010
Six times! Even though it looks like my progress slowed way down, I know that my form got better each time, with deeper squats and more locked-out overheads. Today I started push jerking when push presses got too wobbly, and that definitely got me through the last round. And this WOD, well, it's a tough one to make big gains on. So I'm very happy with today.

I get frustrated sometimes when new people come in and they can do the same weights as me. But when I look at that history and see how far I've come, it helps me to think of it in a new way. People who come in and lift heavy and do well right away are seasoned athletes. They may be new to CrossFit, but they are not new to sports and conditioning. When I came in, I was a complete novice. I had no idea how to do any of the movements and no base of metabolic conditioning or strength. Basically, what I've accomplished in the last two years is I've caught up to the athletes. That's great! How could I not be happy about that?

So now that I'm caught up, it's time to get serious and train. :) As part of that, I worked on deadhang pull-ups today before the warm-up. They're my project/skill for the week.

Why you SHOULDN'T wear sunscreen: A guest rant

Today I have guest rant from Mike on why you shouldn't wear sunscreen. If you're like, wait a minute, every doctor/dermatologist/magazine/newsletter/ad/tv show I've EVER seen says the opposite, ask yourself if any of those sources is a chemist. Mike is, he knows how this stuff works. Give it a read.
#1 - Sunscreen protects you from burning, tanning, producing vit-D, not cancer. UV light, just like visible light, has "colors". For visible light we call those colors "red", "green", "blue", etc., but for UV the names are things like "UVA", "UVB", "VUV","XUV", etc. Just like things interact differently with different colors of visible light (leaves look green because they preferentially absorb red light), things also interact differently with the different colors of UV light. Some colors of UV light work on the surface of our skin to make vit-D (and about a dozen other photoactive compounds whose purpose still isn't known, but since the body doesn't like to waste energy, you can bet they're important somewhere). Other colors cause you to tan or burn, and some damage the DNA and can cause cancer.

Now it turns out that people can easily recognize burning, as it happens pretty quickly and is quite unpleasant. So the sunscreens are optimized to work in the region of the UV spectrum that prevents burns. The trouble is that 1) it also prevents tans and 2) it prevents vit-D production. The tan is your body's own protection mechanism, as it is designed to interact with the high-energy UV to prevent DNA damage, and vit-D is a backup protection - one of its main jobs is to repair damanged DNA. So when you put on sunscreen you are preventing burning (good), but not getting tan (bad), and not getting any vit-D (bad). The high-energy UV radiation isn't stopped by the sunscreen and it still damages the DNA on your skin, but now you have no tan nor vit-D to protect yourself.

#2 - Without sunscreen you can increase your risk of some kinds of skin cancer, but this kind of cancer is harmless, grows slowly, doesn't spread. With sunscreen you're protected from the 'harmless' cancers, yet the nasty stuff (melanoma) is not affected. In fact it can be worse since again, you have less vit-D for your body to fight the melanoma.

#3 - The kind of compounds that interact with UV light generally are long-chain conjugated hydrocarbons, typically lots of phenyl and benzyl groups. Since I can't draw pictures here, I won't go into all the details, but the structure of those compounds is such that makes it very easy for them to interact with DNA. So now you get these photoactive organic compounds on your skin and you hit them with UV radiation. They make free radicals and start reacting with your DNA. So while the compounds themselves are safe (you can't sell them if they're not), they are no longer safe once they are absorbing UV radiation (doing their job as sunscreen).

Also, since we live the paleo lifestyle...what did Johnny Caveman do? He just slowly got tan in the spring and was all set for summer. No need for sunscreen.

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