A Study on the Effects of Forest Therapy on Sarcopenia

Background and Rationale: Sarcopenia is a common skeletal muscle disease in the elderly characterized by the loss of muscle mass, strength, and physical performance. While resistance training and nutrition are core management strategies, Forest Healing has been shown to reduce stress (cortisol), regulate the autonomic nervous system, and improve immune function. This study aims to validate a standardized "manualized" forest healing intervention for sarcopenia, utilizing a cross-border collaboration framework between Taiwan and South Korea.

Study Design & Environmental Monitoring: This is a single-arm, pre-post intervention study (quasi-experimental design) conducted at the Caoling Shibi Forest Healing Base (altitude 1,500-1,700m). A unique aspect of this trial is the quantification of environmental factors, including phytoncide concentrations, negative ions, and thermal comfort indices (PMV, PPD), to explore the mechanistic relationship between the forest environment and physiological adaptations.

Intervention Protocol: The standardized 180-minute sessions are designed to integrate physical conditioning with psychological relaxation. The technical protocol dictates:

Aerobic and Balance Training: Forest trail walking maintained at a Rating of Perceived Exertion (RPE) of 12-13.

Resistance Training: Elastic band exercises targeting upper and lower limbs (3 sets of 8-10 repetitions) at an RPE of 9-13.

Core Forest Therapy: Sensory awareness, aromatherapy, and deep breathing to promote parasympathetic activation.

Psychological Promotion: Facilitated group interactions and experience sharing to enhance social connection and intervention adherence.

Safety Protocol: To ensure participant safety in a mountainous terrain, the study has established a comprehensive three-tier medical safety mechanism. This includes on-site first aid by certified instructors, local AED medical services, and a dedicated emergency medical "green channel" established with the National Taiwan University Hospital, Yunlin Branch.

Inclusion criteria

• Female aged 55 years or older.
• Meet the AWGS 2025 criteria for sarcopenia (low handgrip strength and low skeletal muscle mass index).
• Able to walk independently or with assistive devices and safely participate in low-to-moderate intensity exercise training.
• Willing to commit to the 8-week intervention (16 sessions total) and provide signed informed consent.

Exclusion criteria

• History of major acute illness, hospitalization, or surgery within the past 3 months.
• Severe cardiovascular, respiratory, or other systemic diseases that make moderate-intensity exercise unsafe.
• Severe osteoarticular or neurological disorders that significantly impair walking or exercise safety.
• Severe cognitive impairment that prevents understanding of study procedures or cooperation with the intervention.
• Presence of implanted medical devices (e.g., pacemakers) that would interfere with bioelectrical impedance analysis (BIA).
• Regular participation in structured resistance training or high-intensity exercise within the past 3 months.