Table 1.
Data from the included studies.
| Reference (Country) | N | Age | Control Group | Intervention Group | Outcomes (Unit) | Duration of the Intervention | Full Description of the Intervention |
|---|---|---|---|---|---|---|---|
| Mean ± SD | |||||||
| Bang et al. [37] (South Korea) | 99 | 24.3 ± 4.19 | No intervention | Nature therapy | Physiological: | 6 weeks | The campus forest-walking program was conducted once per week during lunch. The university campus has many different trees, and there are nearby forest roads and trails. |
| M = 21 | M = 26 | Blood pressure (mm Hg) | |||||
| F = 27 | F = 25 | ||||||
| Bielinis et al. [38] (Poland) | 62 | 21.5 ± 0.18 | City intervention | Nature therapy | Psychological: POMS, PANAS and ROS. | 1 day | The field experiment was winter season. Two locations were selected: the urban and the forest environment (deciduous, broad-leaved urban forest situated near the city centre). |
| M = 18 | M = 18 | ||||||
| F = 13 | F = 13 | ||||||
| Jia et al. [35] (China) |
18 | 61–79 | City intervention | Nature therapy | Physiological: Cortisol (ng/mL) | 7 days | The study was performed at two different sites (nature and city). On the day before the study, blood samples were taken from the participants in the morning before breakfast. |
| M/F = 8 | M/F = 10 | ||||||
| Choe et al. [42] (United Kingdom) | 66 | 16–62 | Indoor environment | Natural environment | Psychological: PANAS | 6 weeks | The study consisted of an experiment of three different environments: natural outdoor, built outdoor, and indoor environments. The intervention was in groups of between 6 and 10 participants. Each weekly session lasted one hour and included mindfulness meditation/exercises and group discussion. |
| M/F = 33 | M/F = 33 | ||||||
| Janeczko et al. [39] (Poland) | 75 | 19–24 | Urban area | Nature therapy | Psychological: POMS, PANAS, and ROS. | 1 day | The outdoor experiment was conducted in four different settings: (1) an urban environment with a noticeably higher level of noise, (2) the scenery of urban housing, (3) the Sobieski Forest, and (4) a coniferous forest. |
| M/F = 45 | M/F = 30 | Physiological: Blood pressure (mmHg). | |||||
| Kim et al. [40] (South Korea) |
38 | 22 | No intervention M/F = 19 | Nature therapy | Psychological: POMS and SRI-MF | 2 months | An eight-session forest therapy program was performed once per week, and each session lasted for 1.5 h. Participants were involved in many activities, such as forest dance, forest meditation, forest exercise, walking, and others. The main purpose of the program was to reduce stress and improve the self-esteem of the participants. |
| M/F = 19 | |||||||
| Kim et al. [41] (Korea) | 38 | 22.1 ± 1.6 | No intervention | Nature therapy | Psychological: POMS and SRI-MF. | 8 weeks | The participants were instructed to perform individualized, voluntary forest activities for a one hour-long session per week. The activities included stretching, breathing, walking, meditation, and exercise. |
| M/F = 19 | M/F = 19 | ||||||
| Razani et al. [36] (United States) | 75 | >18 | Independent park prescription | Supported park prescription | Psychological: PSS10 | 3 weeks | The outdoor experiment was conducted in three different sceneries: a bayfront park with a beach, a lake with woodlands, and a redwood forest. Outings concluded with quiet reflection and an opportunity to share experiences. |
POMS: Profile of Mood States questionnaire; PANAS: Positive and Negative Affect Schedule; ROS: Restorative Outcome Scale; SRI-MF: Stress Response Inventory; PSS10: Perceived Stress Scale—10 items; M: male; F: female; and SD: standard deviation.