Stretching and Flexibility: Everything You Never Wanted to Know

TL;DR — A 68-page 1990s internet FAQ on the physiology and types of stretching, still one of the most thorough free guides.

Version 1.42 (June 1998), compiled by software engineer Brad Appleton from the rec.martial-arts and fitness newsgroups. It covers the physiology of muscle stretch, types of stretching (ballistic, dynamic, static, PNF and others), how to stretch properly, and specific exercises. Appleton permits verbatim copies at no charge.

What it is: a well-researched amateur reference from the Usenet era, with a medical disclaimer. Some sports-science claims are dated.

Where this came from

• r/obscurePDFs post, February 2020 — “Stretching and Flexibility: Everything you never wanted to know [68 pages]”. Routing record: The obscurePDFs Subreddit
• Archived copy (Google Drive): Google Drive

68 pages. A copy is archived locally against link rot; the header links the original source.