1 3 Eur J Appl Physiol DOI 10.1007/s00421-014-2892-z ORIGINAL ARTICLE Motor point map of upper body muscles M. Behringer · A. Franz · M. McCourt · J. Mester Received: 14 November 2013 / Accepted: 12 April 2014 © Springer-Verlag Berlin Heidelberg 2014 homogeneity. All MPs were found to be highly symmetri- cal between both sides of the body (r = 0.96; p < 0.001). Conclusion The presented data and the corresponding map will help physiotherapists, and conditioning specialists improve their neuromuscular electrical stimulation therapy or training, respectively. Keywords Neuromuscular electrical stimulation · Motor entry point · Motor branch · Upper body Abbreviations NMES Neuromuscular electrical stimulation EMG Electromyogram LPN Lateral pectoral nerve MP Motor point MPN Medial pectoral nerve RE Reference electrode SD Standard deviation Introduction The fact that electrical stimulation can induce muscle con- tractions has been known as early as 1790 (Cambridge 1977). Early clinicians used this knowledge in attempt to restore muscle function in patients suffering from damages of the nervous system (Althaus 1873). Nowadays, physi- otherapists all over the world still apply electrical stimuli for the same purpose. However, neuromuscular electrical stimulation (NMES) has evolved, and NMES is now suc- cessfully used in a broad range of applications ranging from rehabilitation to high-performance sport. Comprehen- sive reviews of attainable effects and settings that govern the stimulation protocol can be found elsewhere (Doucet et al. 2012; Filipovic et al. 2011, 2012). Abstract Purpose The purpose of the present study was to system- atically investigate the upper body motor point (MP) posi- tions of selected muscles and to create an atlas of the iden- tified MPs. Methods MPs were searched bilaterally in 15 male and 15 female subjects by scanning the skin with a special pen elec- trode at low stimulation frequency (3 Hz) and current ampli- tude (<10 mA). The following muscles were investigated: biceps brachii, triceps brachii, deltoideus, trapezius, latissi- mus dorsi, erector spinae (lumbar part), pectoralis minor and major, and rectus abdominis. Results A total of 1,563 MPs were identified. The MPs could be clustered into 31 distinct positions on each side of the body. However, the number of MPs per muscle var- ied between subjects: 2 MPs were found for the biceps brachii, 2–3 for the triceps brachii, 4–5 for the deltoideus, 2–3 for the pectoralis major, 1 MP for the pectoralis minor, 4–5 for the trapezius, 3–4 for the latissimus dorsi, 4–5 for the rectus abdominis, and 2–3 for the erector spinae in its lumbar part. Referring to the applied grid, upper limb and lower back muscles presented a low inter-individual varia- tion, whereas MPs of the deltoideus, the pectoralis major, and the rectus abdominis were characterized by a poor Communicated by Dick F. Stegeman. Electronic supplementary material The online version of this article (doi:10.1007/s00421-014-2892-z) contains supplementary material, which is available to authorized users. M. Behringer (*) · A. Franz · M. McCourt · J. Mester Institute of Training Science and Sport Informatics, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933 Cologne, Germany e-mail: behringer@dshs-koeln.de