The meaning is in the name, de-load is a phase of training where we ease back on the intensity, load and sometimes frequency of training to give the body a rest. Week in week out clanging and banging for a period of time, takes its toll on your entire body i.e. nervous system, muscle, joints, tendons, cartilage, ligament.
Extended bouts of training will only hinder your performance due to the accumulated onset of fatigue which will lead to training plateau. Simple taking a break or easing back on your training might just be the antidote needed to progress.
There isn’t a best time to de-load, experts will usually recommend 4-6 week as a maker. Your approach to de-loading should always be proactive rather than reactive. Most people tend to force this period when they are getting weaker, less productive, soreness in joint or plateau.
Type of de-load is another issue, there isn’t a right or wrong approach either. Generally most training type usually focuses solely on one or few aspect of training while neglecting or under-utilising others i.e. bodybuilding can neglect cardiovascular and mobility work. In this case, a de-load week can be planned around this. It can also be an adoption of a completely different type of activity entirely for a period of time.