Resistance is a property of a well balanced, well functioning body (A WELL ADJUSTED BODY). The greater your resistance the more stress your body can handle without effect. Stressors at this level are like a speed bump that you quickly pop over and past.
Low resistance means only a small amount of stress can be handled before your body blows out! This level is like treading water; you just keep a handle on the most basic day-to-day stress. Any extra immune, emotional, physical or chemical stressors quickly overwhelm the body, leaving you in a state of bother. Lots of you will easily relate to this feeling of just keeping your head above water!
If the stressors continue to overwhelm your resistance, the sympathetic nervous system will go onto overdrive. Leading to an overactive state where the body is constantly frantic, fatigued, sleeping poorly, hard to switching off, restless, irritable, moody, and to top it off a foggy/fuzzy head.