Electrode Placement (SENIAM)
Over the pars abdominalis (lowest fibres), close to the sternum - of three sites compared, the medial one yielded the highest activity
Orientation: Along the muscle fibres, 2 cm inter-electrode distance
Król H, Sobota G, Nawrat A. Effect of electrode position on EMG recording in pectoralis major. J Hum Kinet. 2007;17:105-112.
Methodological background of the source
Król et al. (2007) specifically investigated how strongly electrode position affects the EMG signal of the pectoralis major. The muscle consists of three portions (clavicular, sternocostal, abdominal) with different fibre directions — the study shows that each portion needs its own electrode location. That portion-specific position is documented here.
Recording notes per Criswell 2011, site „Pectoralis Major (Clavicular and Sternal)“, p. 307
- Placement type
- Specific site The signal originates predominantly from this muscle.
- Signal check
- Flex the arm, abduct above 90°, medially rotate or horizontally adduct.
- Crosstalk from
- anterior deltoid · sternocostal portion of pectoralis major · pectoralis minor
- Artefacts
- ECG (especially on the left side).
Based on SENIAM recommendations (Hermens et al. 2000). Not an official SENIAM product. See all references → · How electrodes are placed (guide) · Glossary
Anatomy
Test Movement
Pull arm from elevation downward-inward against resistance
This muscle has no SENIAM-standardized electrode position. Placement should be based on anatomical knowledge.
MVC reference test (Konrad 2005)
- Position
- Prone on a bench pressing against a fixed long bar, or a push-up position; both at 90° elbow flexion. Seated alternative: both hands press a rigid block in front of the chest.
- Fixation
- Very good shoulder and back support is the decisive factor in every variant.
- Resistance
- Fixed bar (prone) or the floor (push-up); pressing / horizontal adduction against it.
- Control exercise
- The pectoralis test is itself the control exercise for the triceps.
Konrad: numerous test positions are possible; the bar and push-up variants are the easiest to arrange. Compare the clavicular, sternocostal and abdominal parts in different arm angles.
Konrad P. The ABC of EMG. Noraxon; 2005, p. 31. Konrad describes this test at group level; it applies to all muscles of the group. · Why and how to normalise to MVC
Measure M. Pectoralis Major Pars Abdominalis activity live
The electrode is placed — what next? easyEMG visualises muscle activity in real time, with SENIAM-compliant placement guidance, up to 4 channels at once and biofeedback training right afterwards.
In rehabilitation, the Pectoralis Major (Abdominal Head) is typically recorded to track progress and retrain activation.
Frequently Asked Questions
Where do I place the EMG electrode on the M. Pectoralis Major Pars Abdominalis?
Over the pars abdominalis (lowest fibres), close to the sternum - of three sites compared, the medial one yielded the highest activity. Orientation: Along the muscle fibres, 2 cm inter-electrode distance. Not covered by SENIAM — placement per Król et al. 2007.
Which test movement activates the M. Pectoralis Major Pars Abdominalis?
Pull arm from elevation downward-inward against resistance. It serves as a signal check before recording: with correct electrode placement the EMG amplitude rises clearly during this movement.
Is the M. Pectoralis Major Pars Abdominalis a SENIAM-recommended muscle?
No. The M. Pectoralis Major Pars Abdominalis is not included in the official SENIAM catalogue. The electrode position documented here follows the established protocol per Król et al. 2007.