The participants will be instructed to work while taking Methylphenidate and walking on a treadmill workstation

The participants will be instructed to work while taking Methylphenidate and sitting at a desk

The participants will be instructed to work without taking Methylphenidate while walking on a treadmill workstation

The participants will be instructed to work without taking Methylphenidate while sitting at a desk

walking on a treadmill workstation next to desk with computer and screen

The Stroop task measures selectivity and distraction and evaluate the inhibitory ability. In this task a word is displayed in two coloured rectangles. Three states are included: Neutral state- where the word is colored in black; Congruent state- word's meaning and its color correspond; Non-congruent state- word's meaning does not match the color. For each state, parameters are shown separately. Calculated parameters include Mean reaction time of correct responses± the standard deviation of correct reaction times and errors- number of incorrect responses, where subjects pressed the wrong key. The scale of mean response time displays the mean score number of milliseconds for a subject to response (higher number present longer time of response- worse outcome). Higher standard deviation indicates larger distribution among the averages of the subjects. Errors count the times that subjects made mistakes in their answers starting from zero- higher score means worse outcome.

Barhatt performance is a validated questionnaire that includ 30 statements designed to assess impulsivity. The values on a 4-point scale rang from 1 ("never/rarely "), 2 ("sometimes"), 3 ("frequently"), and 4 ("almost always/always"). These statements create three subscales/ dimensions: 1. Motor Impulsiveness (MI), which reflects action without forethought (for example, "I do things without thinking"), 2. Attentional Impulsiveness (AI), which reflects a reduced ability to maintain attention toward a stimulus (for example, "I concentrate easily"), and 3. Non-Planning Impulsiveness (N-PI), which reflects an emphasis on the present (for example, "I am more interested in the present than the future"). In all these three dimensions higher mean score represent higher impulsivity.

Number and length of breaks the participants took from their cognitive work. The values represent the mean number of breaks subjects took during their working time, higher numbers represent more breaks. As well the mean time of breaks in minutes where higher number represents longer time of break.