Before we dive into this topic, now is a good time to define what I mean by the term "isometric", in relation to exercise. I am taking a broad definition of isometrics to include the following types of exercises:

TRADITIONAL ISOMETRICS - This includes exercises in which you push or pull against an immovable object, or pit muscle against muscle with no movement involved. These types of isometrics are sometimes also referred to as overcoming isometrics.

THRESHOLD ISOMETRICS - This is basically traditional isometrics performed in a method that allows force to actually be measured as the exerciser attempts to break through one "threshold" after another. Examples would include : Attempting a barbell curl with a weight sufficiently heavy enough that only a partial curl can be performed. The partial curl would be performed with maximum effort for 10 to 15 seconds at each session until a complete curl could be performed, at which point weight would be added and the process repeated; Using a bullworker device that allows the exerciser to measure how far he or she pushes or pulls the handles. With continued training, the exerciser will be able to compress or pull the device further, thus breaking through measurable "thresholds".
 
STATIC CONTRACTION - This involves holding a weight statically (or without movement) for a pre-determined period of time, attempting to prevent the weight from moving. This can be performed with free weights, weight machines, bodyweight exercises, or even with resistance bands (with the band held in a maximal stretched position). When static contraction exercises are performed with the muscle in the contracted position, this is referred to as Max Contraction training. Static contraction training in general is also referred to as yielding isometrics. Static contraction exercises can be performed either in the strongest-range of motion or in the stretch-range of an exercise movement.

MIXED TRAINING - This involves traditional exercise repetitions in which a slight isometric pause (usually 5 seconds) is incorporated within each repetition. An example would be performing resistance band curls in which, at the top of the curl when the band is stretched, the peak contraction position is held for a count of 5, before lowering the band and proceeding to the next repetition. This type of training is called power-pause. A variation of this involves a series of isometric pauses at different points during the range of motion. An example would be performing a chin-up, then on the way down, stopping and holding various positions for 5 to 10 seconds. This is referred to as isometric stops.

We will explore all of these concepts in greater detail in future posts.