The document discusses different types of stretching exercises including static stretching, PNF stretching, and ballistic stretching. It provides guidelines for safely performing each type of stretching and explains their differences. Static stretching involves slowly stretching a muscle and holding for 15-30 seconds while PNF stretching involves contracting the muscle before stretching. Ballistic stretching uses gentle bouncing motions that should be done after static stretching. The document emphasizes that stretching should not cause pain.

1. Chapter 10: Flexibility Lesson 10.2: Improving Flexibility Taking Charge: Building Intrinsic Motivation

11. Lesson 10.2: Improving Flexibility Question What is meant by the term PNF stretching ?