Here is an interesting little video from Life Noggin on what causes cramps. 

I personally believe in stretching.  A good dynamic stretch routine prepares you for exercise, and a nice static stretching routine after exercise is a relaxing way to cool down.  According to this article from IFLS, the results are mixed.  It states stretching provides little to no effect for the recreational athlete, and has some benefit for high-level athletes who's sport requires a level of flexibility.  The results are not conclusive, but I say, if it feels good, do it!

Supplements are huge business.  According to the FDA a Dietary Supplements is defined as a product other than tobacco intended to supplement the diet, is intended for ingestion, can not be advertised  for use as a conventional food or as the sole item within a meal or diet,  and that contains one or more of the following:

- A vitamin

- A mineral

- An herb or other botanical

- An amino acid

- A dietary substance used buy humans to supplement the diet by increasing the dietary intake

- A concentrate, metabolite, constituent, extract, or combination of the ingredients listed above.

Since there is little regulation, many companies are making false claims on their effectiveness.  Wether you are an athlete or a every day citizen, it is important to if the supplements you are taking are safe and effective.  Click this WebMD link entitled The Truth Behind the Top 10 Dietary Supplements for more information.