An upcoming trend showing great potential in healthcare related applications is the technique of bioimpedance (BioZ). This technique is characterized by the capability of measuring several physiological changes, including respiration. The ideal electrode configuration to correctly measure respiration rate and volume is already validated against the gold standard spirometer. However, the influence of forced breathing, which is important when discussing healthcare related problems, on the ability to correctly measure these respirational parameters needs to be studied as well. A wearable, non-invasive and multiparametric device capable of measuring BioZ, ECG and accelerometer data simultaneously was used. BioZ data was sampled at a fixed and single frequency of 1024 Hz. ECG and accelerometer data were sampled at 512 Hz and 32 Hz respectively. Subjects were asked to perform the spirometry test twice, in which they had to take the deepest breath manageable followed by an expiration as hard and long as possible. Both spirometry measures were segregated from one another by normal breathing. The measurements were performed with the wearable device and gold standard spirometer simultaneously. Different electrode positions varying in height on the midaxillary line were tested. The electrodes positioned at the level of the nipples resulted in the largest impedance sensitivity during both normal and forced expiration. A pattern emerged when the electrodes were positioned lower. The hard expiration was characterized by an elevation in the bioimpedance signal. This unexpected shift in bio-impedance could be explained by the movement of the diaphragm-liver mass that moves upwards during forced expirations or the turbulent ventilation and small airways collapses. The position of the electrodes on the midaxillary line influences the impedance sensitivity when measuring during forced or heavy breathing. The ideal position to measure both normal respiration and forced expiration is located on the midaxillary line at the level of the nipples.