This paper attempts to determine the extent to which driving automation can reduce physiological stress in drivers with disabilities. Understanding the mechanisms that shape muscle tone in these drivers is an important element of ergonomic design research. This analysis enables the assessment of the impact of new assistive technologies on the physiological aspects of driving and provides a basis for the universal design of vehicle adaptation systems that minimize the risk of muscle strain. The aim of this paper is to analyze the impact of selected autonomous vehicle functions on muscle tone in drivers with disabilities. The paper utilizes a quantitative method to determine muscle tone levels using electromyography during the use of adaptive devices. The data was filtered and threshold values were determined. It was observed that in able-bodied drivers, muscle tension decreased by an average of 12 percentage points when the features were enabled. Distributing the results by upper limb, the results showed a 10 percentage point increase for the right hand (accelerator and brake) and a 13 percentage point increase for the left hand (steering wheel). The results for individuals with paraplegia were also separated; the assistance features increased their muscle tension by an average of 4 percentage points. The corresponding figures were 7 percentage points for the right hand and 1 percentage point for the left hand. The study addresses the potential use of intelligent safety systems, which will be standardly installed in passenger cars from 2024. Interpreting the average results, a reduction in muscle tension was observed in the studied drivers using the assistance features.