Autonomic Response Testing is a non-invasive, diagnostic method used to assess the health and functioning of the autonomic nervous system (ANS). ​​A.R.T. uses muscle testing to evaluate how your body responds to various stressors, including toxins, infections, environmental and emotional stressors. ​Developed by Dr Dietrich Klinghardt, A.R.T. is a very simple yet reliable method to get to the root cause of your illness.