There are few new strength training approaches. There are lots of new products, but few original ways to exercise that provide something uniquely valuable. Spin Strong is the rare exception. It takes a well known type of resistance - air resistance - and delivers it in a well known form - arm spinning movement - which jumping rope has shown, provides excellent conditioning. However, Spin Strong delivers it with freedom of movement that allow new strength and cardio exercise that improves functional and sports performance.

Jumping rope is great cardio, but is likewise excellent upper body conditioning exercise. Considering how the jump rope constrains arm movement to one arm spinning exercise, just imagine how valuable three, six or even nine different of these exercises would be.

Spin Strong delivers nine different exercises and many variations. The specific details of how Spin Strong creates the resistance, the complex body mechanics involved and why this type of strength training is so valuable will be covered here.

Circular Arm Movement and Air Resistance

Spin Strong is the first portable and handheld spin trainer based on air resistance.  Consisting of air-catching fin-cords attached to jump rope style handles, you move your arms as if you were jumping rope. 

Spin Strong’s fin cords are short jump rope cables with fin modules attached to the cables. There are three fins symmetrically positioned around the fin modules. The layout is similar to that of feathers around the tails of darts or arrows. As the fin modules attached to the cords are spun through the air, the air hits the symmetrical fin modules with balanced amounts of force on each side of the cord.  generating balanced continuous air resistance, as shown in the graphic below.

Rotary Or Circular Arm Training Mechanics | Spin Strong

Air resistance opposes forward movement

Air resistance opposes an objects forward motion. In the case of circular movement, it’s constantly changing direction, but it’s the same principal. Air resistance provides continuous and directly opposing force to an arm’s “forward”movement along the path of the circle, or around the circle, as shown in the graphic below. 

Rotary Or Circular Arm Training Mechanics | Spin Strong

Weights like dumb bells do not provide this kind of direct opposition. They are always exerting a downward force. An arm has to move a dumb bell around while holding it up in the air.

Complex and interrelated arm/shoulder movements

Spin Strong Rotary Training combines air resistance and circular arm motion. This is very complex movement. It includes muscles and joints from the hand, up the arm to the shoulder, and down into the core. All major joints are included.


The Spin Strong Training Musclle Diagram | Rotary Or Circular Arm Training Mechanics | Spin Strong

The wrist joint is a circular joint and has full range of 360 degree movement. The elbow joint has 180 degree range of movement up and down, in terms of flexing and extending the arm, as well as almost 180 degree rotation of the lower arm. The shoulder joint, the most complex joint in the human body, is a circular joint also, and has a full range of 360 degree movement. The following picture shows the movement of these three joints.

Rotary Or Circular Arm Training Mechanics | Spin Strong


Four arm movements in one

A circular movement of the arm or wrist is called circumduction. It equals four sequential movements of flexion (up), abduction (out), extension (down) and Adduction (in) as shown below.


Picture of an arm circle equals four sequential arm movements | Rotary Or Circular Arm Training Mechanics | Spin Strong

Circular arm motion using the shoulder joint includes these four sequential movements. Circular wrist action includes four more arm movements. The arm is constantly flexing and rotating the lower arm using the elbow joint (which includes secondary joints). So each arm circle includes at least 10 sequential and interrelated arm movements. This is incredibly complicated. And it is happening close to two hundred times a minute.


Strengthens all major muscles of arms and shoulders

These movements engage and strengthen all the major muscles of the arms and shoulders. The hands are gripping the Spin Strong handles. Forearms are highly engaged in finger, hand and wrist movements. Biceps and triceps are engaged in elbow and shoulder movement. All the muscle of the shoulders are involved, as well as muscles of the upper body and the core.

This training builds fast twitch muscles for speed. Yet, it also increases the kind of strength that improves endurance. This exercise has been appreciated indirectly in that it is the arm action used in highly respected jump rope exercise. But now, it can be appreciated in its own right. The many different rotary exercises that can be done with Spin Strong show the true potential of this extensive and unique training for the upper body and especially the arms and shoulders.