Paleo diets are based on a simple premise – if the cavemen didn’t eat it, you shouldn’t either. So long to refined sugar, dairy, legumes and grains (this is pre-agricultural revolution), and hello to meat, fish, poultry, fruits and veggies. The idea is that by eliminating modern-era foods like highly-processed carbs and dairy, you can avoid or control “diseases of civilization” like Type 2 diabetes and heart disease, and likely lose weight too. What you eat and how much depend on your goals or the specific program you’re on, if you choose to follow one. The high-protein diet is ranked poorly among U.S. News experts, who consider it too restrictive to be healthy or sustainable.
With a very simple shift we not only remove the foods that are at odds with our health (grains, legumes, and dairy) but we also increase our intake of vitamins, minerals, and antioxidants. Here is a great paper from Professor Loren Cordain exploring how to build a modern Paleo diet: The nutritional characteristics of a contemporary diet based upon Paleolithic food groups. This paper also offers significant insight as to the amounts and ratios of protein, carbohydrate and fat in the ancestral diet.
This 2003 CrossFit Journal article captures an early conception of a universal, multi-event test of fitness that laid the foundation for CrossFit competition, including what would become the CrossFit Open and the CrossFit Games. The design requirements for such a test "included but were not limited to the following: quantifiable results; consistency with the CrossFit fitness concept; raising our commitment to improving absolute strength, relative strength, and gymnastic foundations; balancing intrinsic abilities of smaller and larger athletes; emphasizing exercises critical to and foundational to advanced training; mixing training demands within each test and, of course, over the total competition; a design that would identify an athlete’s weaknesses and possibly stand as a workout plan for improving overall fitness; and, finally, we wanted to design a competition that would be 'hard as hell.'"