-extremely short training sessions, typically just 2 all-out sets
-totally exhausting the involved muscles
-6 to 10 reps for upper body, 12 to 20 reps for lower body
The HIT method is an unorthodox way of building muscles, first introduced in 1970’s by Arthur Jones and popularized by such giants in the world of bodybuilding as Lee Labrada, Sergio Oliva and Dorian Yates.
High Intensity Training goes against several established rules of conservative muscle building theory but the method is based on logical presumptions and more than 3 decades of experience so it should be considered by every serious bodybuilder at some stage of his/her training.
The basic principles of HIT
The pure HIT program is based on the principle that it is enough to make just one all-our set of an exercise (accompanied by 2 or 3 warm-up sets) to achieve the stimulation necessary for muscle growth. So the whole training may consist of 2 exercises, each consisting of 2 or 3 warm-up sets and one exhausting set which should exhaust the involved muscles as much as possible.
Since the basic theory underlying the muscle growth stipulates that the muscle must be exhausted and possibly hurt and the growth takes place during the repairing/resting period, there seems to be no reason why one should repeat the strain again and again (by adding more sets).
On the contrary, say the HIT followers. More sets of the same exercise are not only useless but indeed counterproductive.
In order to produce results, the theory goes, each “effective” set must lead to a complete failure of the involved muscle. The concept of muscle failure is exactly specified in the HIT theory and consists of three phases:
Phase 1. First stage of failure comes when the trainee is unable to complete the exercise, that is to lift the weight as required. Still, it is possible to hold the weight, say, in the mid-trajectory of the exercise.
Phase 2. Second stage of failure comes when the trainee is unable to even hold the weight passively in the mid-trajectory and has to lower it. Then he/she is required to lower the weight as slowly as possible in order to exhaust the muscle totally.
Phase 3. Third stage of muscle failure comes after the trainee lowered the weight in a slow and controlled movement and is unable to lift it again.
I have to stress that holding the weight with stretched arms or legs (as you do e.g. when you lift the barbell at bench press) is not considered helpful. Holding the barbell in mid-trajectory at bench-press refers to holding it in the mid-way to stretched arms. Of course, you must be very careful when practicing total exhaustion with certain exercises and especially with the bench press.
The cadence plays a significant role in High Intensity Training. Compared to other workout methods the HIT cadence is slow, typically 3-1-4-1 (3 seconds lifting, 1 second holding, 4 seconds controlled lowering, 1 second holding).