Introduction: Expanding upon prior investigations that identified advantageous Far Infrared (FIR) properties associated with two minerals, namely tourmaline and terahertz, across diverse domains, including health and medicine. This study explores the impact of incorporating fine powders of these minerals into printing ink for patterns on shirts on HRV when wearing the shirts.

Methods: A total of 12 healthy adult males were surveyed in this study. Fine powders of the two minerals, tourmaline, and terahertz were incorporated into printing ink and used to print patterns on shirts. The impact of wearing these shirts on HRV was observed.

Result: The significant differences in time-domain analysis parameters such as SDRR and RMSSD, frequency-domain analysis parameters including Total (ms2), VLF (ms2), LF (nu), HF (ms2), and nonlinear analysis parameters SD1 and SD2 were observed.

Conclusion: The findings suggest that both short-term and long-term wear of shirts containing these minerals lead to an increase in vagal nerve tension. Participants wearing shirts with mineral inclusions exhibited changes related to vagal nerve activity.