The back isolator with the expander is from the movement execution an opposite movement of the butterfly for the chest musculature. Since the wrists are not moved to the upper body but to the side during this exercise, the upper middle back muscles are put under increased strain.
Muscles involved
- Tail muscle
- Trapezius muscle
- Wide back muscle
The expander is securely attached in front of the body. Both ends are wrapped around the wrists and held firmly in the hand. The upper part of the body is in a light upper body position.
To allow the spine a larger contact surface, the athlete stands in a crotch position. The hands are stretched out in front of the body at shoulder height. The expander is already pre-stretched.
In the movement version, the expander belt is guided to the side of the body. The upper body moves as little as possible. The entire movement must be slow and controlled. To ensure safety during training, the expander must be checked for proper condition before each training session.
Safety during expander training
Even though the expander does not represent a weight, this form of strength training is not without danger. During many exercises there are high pulling resistances where the expander band can tear. Before a training session, the expander should therefore always be checked to ensure that it is in perfect condition and replaced if necessary.
