Table 3.
Included studies.
| Study | Study design | Slow breathing technique group | Control group | Mean age [control group] | Slow breathing technique | Slow breathing technique details | Comparison technique | Comparison technique details |
|---|---|---|---|---|---|---|---|---|
| Critchley et al., 2015 | Within subjects | 20 (8 female) | No control group | 34.5 | Paced breathing (5.5 b/min; 10 b/min) | 1 min each frequency | Spontaneous Breathing | 1 min |
| Edmonds et al., 2009 | Within subjects | 14 (6 female) | No control group | 33 | Paced Breathing (6 b/min) | I/E = 1/1 + pause; 1/1 no pause; 1/2 + pause; 1/2 no pause | Spontaneous breathing | 5 min |
| Fumoto et al., 2004 | Within subjects | 22 (6 female) | No control group | 21–54 years | Voluntary abdominal breathing (Zen Tanden breathing) (3–4 b/min) | 20 min | Spontaneous breathing | 20 min |
| Gross et al., 2016 | Within subjects | 9 (6 female) | No control group | 45.88 | HRV biofeedback (6 b/min) | 6 sessions (5 min with peacer + 5 min without pacer) | Spontaneous breathing | 5 min |
| Gruzelier et al., 2014 | Pre-post design | 16 | 16 | Unknown (I year bachelor students) | HRV biofeedback (6 b/min) | 10 sessions (20 min each) | Non-intervention control group | Non-intervention control group |
| Kharya et al., 2014 | Pre-post design | 20 (10 female) | 20 (Sudarshan Kriya) (10 female) 20 (Control) (10 female) | 18–30 years [18–30 years] | Prana-Yoga (2–5 b/min) | 150 days; 5 days a week; 30 min each session, nostril and mouth | Sudarshan Kriya (3–60 b/min) Spontaneous Breathing (Leisure Walking) | 150 days; 5 days a week 30 min each session |
| Lehrer et al., 2003 | Pre-post design | 23 (16 female) | 31 (22 female) | 30.55 [27.93] | HRV Biofeedback (5.4–6 b/min) | 10 days; 30 min, mouth | Spontaneous Breathing | 10 days; 30 min each session |
| Lin et al., 2014 | Within subjects | 47 (36 female) | No control group | 20.98 | Paced breathing (5.5, 6 b/min) | 2 min each frequency | Spontaneous breathing | 5 min pre + 5 min post |
| Park and Park, 2012 | Within subjects | 58 (22 female) | No control group | Male: 24.8; Female: 24.5 | Paced breathing (10 b/min) | 15 min. I = 2.4 s; E = 3.6 s, nostril | Spontaneous breathing | 15 min |
| Sakakibara et al., 2013 | Pre-post design | 15 (9 female) | 15 (11 female) | 22.8 | HRV Biofeedback (6 b/min) | 3 sessions, 20 min | Non-intervention control group | Non-intervention control group |
| Siepmann et al., 2008 | Pre-post design | 12 (6 female) | 12 (6 female) | 28 | HRV Biofeedback (6 b/min) | 6 sessions, 25 min | Non-intervention control group | Non-intervention control group |
| Stark et al., 2000 | Within subjects | 40 (20 female) | No control group | 24.33 | Paced breathing (9 b/min) | 5 min | Paced breathing (12, 15, 18 b/min) Spontaneous breathing | 5 min each frequency |
| Tsuji, 2010 | Within subjects | 10 (0 female) | No control group | 21.7 | Paced breathing (4 b/min) | 10 min; I = 5 s, E = 10 s, nostril | Spontaneous breathing | 10 min |
| Van Diest et al., 2014 | Within subjects | 23 (n. female non-specified) | No control group | 1–22 years | Paced breathing (6 b/min) | I/E = 3/7, 7/3; 45 s each I/E ratio, nostril | Paced breathing (12 b/min) spontaneous breathing | 7 min |
| Yu et al., 2011 | Within subjects | 15 (1 female) | No control group | 38 | Zen Tanden Breathing (3–4 b/min) | 20 min; I = 6–8 s; E = 9–12 s | Spontaneous breathing | 5 min pre + 5 min post |