Effects of Various Horticultural Activities on the Autonomic Nervous System and Cortisol Response of Mentally Challenged Adults

The objective of this study was to examine how horticultural activities, such as pressing flowers, planting, creating flower arrangements, and making topiaries, affect stres, relief for patients who are mentally challenged Two experiments were conducted in this study In Expt 1, the heart rate variation (HRV) of 30 mentally challenged people from the Daegu Rehabilitation Center (Daegu, South Korea) was measured The pressed flower group and the planting group showed a significant improvement (P < 0 01) in the SD of the normal normal interval HRV measurements (SDNN), which improved from 42 37 to 45 54 ms The planting group', SDNN and low frequency (LF) significantly improved from 38 68 to 45 49 ms and from 5 87 to 6 58 ms, respectively, at P < 0 05 A significant improvement in total power (TP) and high frequency (HF) at P < 0 01 was also observed, results changed from 6 90 to 7 46 ms and from 4 76 to 5 28 ms, respectively The flower arrangement group displayed a significant difference in LF (from 5 26 to 5 89 ms) at P < 0 05 Finally, the topiary group showed a significant difference in TP (from 6 72 to 7 23 ms) at P < 0 05 In Expt 2, the cortisol levels of 20 mentally challenged people from the P Residential Home (Yeongcheon, South Korea) were measured Compared with the baseline measurement, the pressed flower group displayed a significant decrease in cortisol density from 4 66 nmol L-1 on day 1 to 4 64 nmol L-1 on day 7, however, no significant difference was observed on day 4 The planting group showed a significantly decreasing difference (3 08 nmol L-1) in cortisol density (8 84 nmol L-1) on day 7 compared with day 4 of planting activities Finally, the topiary group continued to show a significant decrease (from 9 98 to 7 0 nmol L-1) in cortisol density at each cortisol collection after the first day of topiary activities It was concluded that indoor horticultural activitie have an effect on mentally challenged people's stress relief In particular, planting activities were effective for this relief