The new training device, the eccentric arm-crank, will be examined for its training effect by this project. That the training device can be used in athletes and patients with paraplegia in the future, the so-called "testing of the applicability of this concept" will be carried out during this study. Fourteen volunteer, healthy and trained people are first tested for their upper body performance, followed by a training phase over 20 trainings and at the and the performance data is collected again. The training intensity and duration is continuously increased during the training phase.

At the beginning, the study design includes an familiarisation appointment with performance tests and training on the eccentric arm-crank device (KREHA). At least one week later, the first test sequence including a maximum strength test (bench press), magnetic resonance imaging (MRI) to determine the muscle cross-section area of the upper arm and a test to determine the anaerobic performance (Wingate test) is conducted. The second test sequence takes place one to three days later. This includes a handgrip strength test, an aerobic endurance test (ramp test on the arm crank ergometer with ergospirometry) and a further familiarisation training on the KREHA. The training phase starts within two weeks after the pre-tests have been completed. There are two to a maximum of three trainings per week. These take 30 to 60 minutes and take place on the KREHA device under the supervision of the study staff. The training phase lasts a maximum of twelve weeks (20 training sessions). The first test sequence is repeated five to eight days after the last workout. The second test sequence takes place at the same time interval as in the pre-tests.

Inclusion Criteria:

• male or female
• age between 18 and 50 years
• experience in strength training
• trained (minimum two times a week)
• healthy
• adequately informed and confirmed per signature

Exclusion Criteria:

• findings during anamnesis of study doctor
• pregnancy