Write 5 articles of 2,000-3,000 words each, around a particular topic / concept relating to fitness.

5 topics will be provided in the form of keywords. The purpose is to write an article for each, explaining what this particular keyword is, what's popular/important about it and so on. For example, one keyword will be "Bodybuilding" so write about what bodybuilding is, how people go about it, what type of supplements exist, etc. Another keyword will be "Fat Burner" so write about fat burning supplements, how they work, what to expect, side-effects, etc. The exact structure and content for each topic will be determined by you, but it needs to be useful to a general audience and thoroughly introduce someone to that concept. You need to have prior expertise in the field of diet, fitness or nutrition and the work needs to be original and very informative to the average user looking to learn more about nutrition, weight loss, dieting or fitness. Each article should have a fair amount of detail and technical information. This work should be good and informative enough to be shareable on the web (i.e. other users will find it useful) and be used as a resource page for the particular topic. When applying please use the word "ninjafitness" in the topic so that it's obvious you've read this far and that it's not an automated application. Please also state your qualifications in the fields of fitness, dieting or nutrition.