Chiropractors go to professional college for up to 8 years to learn anatomy, physiology, and all the physical sciences to know how to adjust patients safely. There are also different forms of adjusting techniques that use heavier amounts of force down to techniques that use hardly any force at all. For instance, at Natural Health, we use the Activator adjusting instrument to adjust our patients which is a very low force metered adjusting technique with a stellar safety record. We also use a muscle relaxing technique to move the vertebra which uses no force. Both of these adjusting techniques are extremely safe.