Is this a skin problem or muscle injury?

[Tony Moma]

Below is a current image of my back. The darkened area in my lower-mid back was not always there. It first appeared a couple months ago, and I don't know the cause. At first, I thought it was bacteria build-up from lifting in my sweaty garage every day. So I started washing it imore intensely in the shower with medical soap, but that hasn't made one bit of a difference.

I'm starting to think the problem has to do with the muscle in that area, because during the 8 months leading up to this discovery, I was training deadlifts heavier than ever, lifting 400+lbs for 1 set of 5, 2-3 times per week. Then one day, on a 3rd rep, my back just gave out. That was the first day I noticed the dark area on my back, and it was initially painful to touch. I haven't been able to hit my usual number of reps on deadlifts since. Any thoughts on what this is?

Back - 1.jpg

[Mark Rippetoe]

Might be nothing, might be a melanoma. This is a very good example of the type of thing you don't try to diagnose with some guy on the internet. Get a derm consult ASAFP.