Fig. 3. Means of binned rectified EMG traces of the external intercostal muscle during hissing whilst running. The rectified EMG trace is sampled relative to breath (the onset of expiratory airflow to the end of inspiratory airflow) and relative to stride (peak contralateral limb support to next peak contralateral limb support). The external intercostal demonstrates no respiratory activity; rather bursting activity correlates with contralateral limb support.