Nature based biopsychosocial resilience theory (NBRT) suggests that nature can build and maintain biological, psychological and social resilience resources that can be used at the preventive, response and recovery stages in stress management. Nature-based therapies may have advantages over common evidence-based alternatives for building such resources and supporting healthier coping. We present a factorial randomized controlled trial comparing two established nature-based health interventions - one with and one without mindfulness training as a core therapeutic component - against conventional mindfulness training indoors and a passive waitlist condition. Participants were university students with high rates of stress, depression and anxiety connected to pressures in their academic work combined with life transitions and contextual stressors. The nature-based interventions involved weekly group activities in a campus-adjacent nature preserve while the indoor mindfulness group had activities in a rearranged classroom. Qualified instructors led the groups. Before and after the 5 intervention weeks, a subsample of 83 students were asked to come to a small classroom, typically used for group work and seminars, and complete an individually calibrated task designed to induce cognitive fatigue and psychophysiological stress, with the intention to model high-pressure work under cognitive load. The stressor was followed by a restoration phase consisting of a realistic 20-minute break spent either indoors or outdoors in the university's botanic garden. A combination of task performance patterns, continuous heart-rate monitoring, and subjective ratings measured theorized resilience processes related to each stress stage. Additionally, the factorial pre-/post-intervention design allowed comparative evaluation of the respective therapeutic effects of the nature-based and mindfulness-based intervention components. Data were collected in autumn 2024 and spring 2025, pending analysis in autumn 2025. We will present the resilience-related intervention outcomes and discuss possibilities for further development of the procedure as a standardized yet adaptable evaluation paradigm for therapeutic interventions targeting resilience processes.