Fig. 1: Study protocol and sample recruitment.

Parameters were measured at ‘X’ (T0–T6). TM text message, RM randomization, HR heart rate, HRV heart rate variability, Stress subjective stress level, ECG electrocardiogram.

Parameters were measured at ‘X’ (T0–T6). TM text message, RM randomization, HR heart rate, HRV heart rate variability, Stress subjective stress level, ECG electrocardiogram.