Heart rate variability as an indicator of the beneficial effects of Qigong and mindfulness training on the mind–body well-being of cancer survivors

Background Cancer-related fatigue (CRF) and fear of recurrence (FOR) are frequently experienced by cancer patients. This study aimed to improve cancer survivors’ CRF, FOR, quality of life (QOL), and heart rate variability (HRV) through Qigong and mindfulness interventions. Methods A quasi-experimental design was adopted, and 125 cancer survivors were recruited using snowball sampling. The participants were assigned to 1 of 3 groups (Qigong, mindfulness, and control) based on their needs and preferences. All groups received 4 h of nutrition education at the pretest (T0). CRF, FOR, and QOL questionnaires and HRV parameters were used as the measurement tools. Data were collected at the pretest (T0), posttest (T1), and follow-up (T2). Results Qigong had a better effect on improving CRF (ΔT1-T0 = − 0.108, ΔT2-T1 = − 0.008) and FOR (ΔT1-T0 = − 0.069, ΔT2-T1 = − 0.150) in the long term, while mindfulness improved QOL (ΔT1-T0 = 0.096, ΔT2-T1 = 0.013) better in the long term. Both Qigong and mindfulness had a short-term effect in improving SDNN (Q: ΔT1-T0 = 1.584; M: ΔT1-T0 = 6.979) and TP (Q: ΔT1-T0 = 41.601; M: ΔT1-T0 = 205.407), but the improvement in LF (Q: ΔT2-T1 = − 20.110; M: ΔT2-T1 = − 47.800) was better in the long term. Conclusion HRV evaluation showed that Qigong and the mindfulness interventions had short-term effects in significantly improving overall physical and mental health, self-emotional regulation, and QOL and relieving fatigue and autonomic dysfunction. HRV may serve as an observational indicator of interventions to improve physical and mental health. The consistent practice of mind-body interventions is the primary means of optimizing overall health and well-being.