2.3. Intervention
Participants of both intervention groups spent a seven-day vacation in Algund (Italy, 46°40′57.5″ N 11°07′19.0″ E, 350 m AMSL), a region that is characterized by its mild, nearly Mediterranean climate. All participants were housed in local hotels, got the same meals, and did not receive lifestyle recommendations during the non-intervention phase.The HG took part in guided, moderate hiking tours every day (3–4 h), except for one rest day in the middle of the intervention week. The nature group received daily 3–4 h of standardized nature connection therapy sessions with a psychologist trained for this purpose. Forest therapy was characterized by low physical activity and oriented on a holistic framework that promoted meaningful connections at the three levels of “connection with nature”, “connection with others”, and “connection with oneself”. In forest therapy, each day had a specific theme that was worked on (mindfulness and relaxation, connection to nature, social connections, connection to self, goal setting and next steps). After a practice phase, the participants finished the intervention each day with a written self-reflection. These interventions were conducted in two separate, but identical sequences: The first part of the study population completed the ANKER-Study in October 2019, the second part in June 2021.