The intervention consists of 11 consecutive sessions of forest bathing (one session per week), each one lasting about 2 hours. Each session involves an easy walk through a forest area, interspersed with non-intrusive activities of contact with the surrounding nature aimed at fostering mindfulness and the use of the five senses.

Using emWave Pro Plus device and software

Using INICO-FEAPS questionnaire (Verdugo Alonso et al., 2013): Scale for the Integral Evaluation of the Quality of Life of people with intellectual or developmental disability, developed by the University Institute for Community Integration (INICO) and the Spanish Confederation of Organizations for People with Intellectual or Developmental Disability (FEAPS).

It is a self-report tool that consists of 72 four-point Likert-type items divided among 8 dimensions: self-determination, rights, emotional wellbeing, social inclusion, personal development, interpersonal relationships, material well-being, and physical well-being. Each dimension is composed of nine items. Each subscale score is calculated by summing up the score for each of the nine items, and a total score is then calculated by summing up the scale scores. Higher scores are associated to better quality of life.

Following Höppe (1999) procedure

Using questionnaire published in previous studies (Teli et al., 2012; Trebilcock et al., 2017), that includes 3 items to assess thermal sensation vote (TMV) (7-point Likert scale), one item to assess thermal preference vote (TPV) (3-point scale), one item to assess the feeling of comfort (closed-answer), one item to get clothing information (closed-answer), and one item to evaluate the feeling of tiredness (3-point scale). The answers to these questions put the PET value (outcome 4) into context and help interpret it.