In the human forearm there are numerous muscles for stretching and flexing the fingers and bending, stretching and twisting the whole hand. If these muscles are not used regularly, they will regress and the strength will diminish. This may be the case in a long-lasting illness or after weeks of immobilization of the forearm in a plaster cast. With special training devices for forearms, hands and fingers the strength of the musculature can be trained again. In various sports that require a vigorous grip of the hands, for example when mountain biking or climbing, one can forearm trainer improve stamina significantly. forearm trainer are available in different versions.

A variant of forearm trainer is a 40 cm long, round bar with two soft handles at the ends and a thicker middle part. The middle part is a coil for a pull rope. Different weights can be attached to the end of the rope. For training, the rope with the weight hanging on it is wound on the middle part of the forearm trainer by turning the right and left hand alternately, thus lifting the weight. In this way, especially the muscles responsible for stretching the hand on the upper side of the forearms and the finger strength are strengthened.

Of the forearm trainer by C. P. Sports consists of a solid steel rod with soft sponge rubber handles. The rope for lifting the weights is made of tear-resistant nylon. The weight recording is specially adapted to the inclusion of weight plates.

Allow another training method forearm trainer with two handles, which are mounted in a hollow frame that looks like an 8. There are springs in the frame, which counteract the rotational movement of the hands a certain resistance. The fact that the two handles are connected via the frame, the posture of the arms during training is always the same and the arms are trained synchronously. However, these forearm trainers mainly train the forearm muscle group for the rotation of the hands and finger muscles.

Men’s Health PowerTools‘ Speed ​​Wheel Training Baton, with its two easy-to-use hand movements, makes it possible to imitate the movements of the boxing pear for targeted training of the forearm muscles.

The third version of the forearm trainer are training devices that are dressed like a glove. The front part consists of a handle and a shell, which lies on the back of the hand. The handle is enclosed with fingers. In the area of ​​the wrist, the rear part of the forearm trainer is movably connected to the front part via a joint. The back part is supported on the top and bottom of the forearm. The two ends of a spring are attached to the front and rear of the forearm trainer. During training, the hand is bent against the force of the spring. The spring force is adjustable depending on training progress. In these forearm trainer only the flexor muscles for the hand and to a lesser extent the finger muscles is trained.

With the forearm trainer of the Bad Company, the spring force can be adjusted in a range of almost 5 kg up to almost 25 kg in 5 stages. Also, the grip of the forearm trainer is repeatedly adjustable for optimum hand position.

All three training devices are limited to the training of certain muscle groups in the forearm. To train all the muscles, all three forearm trainers would have to be used. An alternative to this are the so-called Powerballs. Inside these balls a spinning top rotates at more or less high speed. Depending on the speed of the gyro, a correspondingly high force must be used to change the position of the ball. As a result, the muscles of the fingers while holding the ball and the muscles for turning and bending the hand are equally stressed and trained.