Table 1.
Characteristics of the six eligible RCTs with betaine supplementation.
| Author, Year | Country | No. (Control/Intervention) |
Gender (F/M); Mean Age |
Training | Duration | Study Design | Dose of Betaine Intake | Jadad Score |
|---|---|---|---|---|---|---|---|---|
| Cholewa et al., 2018 [20] | USA | 23 (12/11) | (23/0) 21.0 ± 1.4 |
Yes | 9 weeks | Parallel | 2.5 g/day | 4 |
| Cholewa et al., 2013 [18] | USA | 23(12/11) | 18~35 | Yes | 6 weeks | Parallel | 2.5 g/day | 3 |
| Favero et al., 2011 [16] | Brazil | 17 (8/9) | 18~30 | None | 10 days | Parallel | 2.0 g/day | 4 |
| Grizales et al., 2018 [21] | USA | 27 (13/14) | (8/19) 58.9 ± 7.67 |
None | 12 weeks | Parallel | 9.9 g/day | 4 |
| Schwab et al., 2011 [17] | Finland | 63 (31/32) | (50/13) 27.0 ± 8.0 |
None | 24 weeks | Parallel | 4 g/day | 4 |
| Schwab et al., 2002 [15] | Finland | 42 (20/22) | (28/14) 44.2 ± 8.7 |
None | 12 weeks | Parallel | 6 g/day | 4 |
Abbreviations: F, female; M, male; No., number of included subjects.