I'd like the color #ff4351 to be incorporated into the design somehow. This is the only must have requirement.
I also like dumbbells, and scientific symbols like the atomic nucleus, beakers, test tubes, etc.
I like geometric/polygon logos. Perhaps an 'Outlaw' face made of polygons?
Another idea: A strong, fit criminal who is shirtless and covered in tattoos. But the tattoos are all science tattoos like microscopes, DNA, molecular structures, etc.
I'd like an instantly memorable logo that encompasses the important aspects of fitness, and science/evidence. I'm not opposed to playing off the word "outlaw" either in your design. However, I'm NOT particularly fond of western themes.
If you feel like you're up for this challenge then please submit a design! The website is extremely popular and the logo will become synonymous with the fitness industry.
Current website: http://www.outlawfitnesshq.com