Table 2.
Summary of the characteristics of the included studies
| RT | Non-RT | All | |
|---|---|---|---|
| Number of studies | 59 | 24 | 82 |
| Number of participants | 2440 | 1500 | 3940 |
| Age (years) | 45.5 | 72.1 | 55.6 |
| Number of participants aged 19–59 | 1461 | 81 | 1542 |
| Number of participants aged 60–87 | 923 | 1389 | 2312 |
| Sex (men %) | 62 | 38 | 53 |
| Race (Caucasian %) | 88 | 63 | 78 |
| Height (cm) | 171 | 164 | 168 |
| Number of participants (149–169 cm) | 768 | 1022 | 1790 |
| Number of participants (170–185 cm) | 1460 | 329 | 1789 |
| Body weight (kg) | 78.8 | 68.1 | 74.8 |
| Number of participants (46–74 kg) | 672 | 977 | 1649 |
| Number of participants (75–102 kg) | 1631 | 395 | 2026 |
| Body mass index (kg/m2) | 26.6 | 25.4 | 26.1 |
| Number of participants (20.6–24.9 kg/m2) | 768 | 516 | 1284 |
| Number of participants (25.0–37.9 kg/m2) | 1597 | 963 | 2560 |
| Energy intake (kcal/day) | 2141 | 1752 | 2035 |
| Number of participants (1298–1999 kcal/day) | 561 | 418 | 979 |
| Number of participants (2000–3539 kcal/day) | 819 | 100 | 919 |
| Baseline protein intake (g/kg BW/d) | 0.39 | 0.37 | 0.38 |
| Number of participants (0.60–0.99 g/kg BW/d) | 561 | 314 | 875 |
| Number of participants (1.00–2.10 g/kg BW/d) | 1235 | 962 | 2197 |
| Added protein intake (g/kg BW/d) (intervention groups) | 0.39 | 0.37 | 0.38 |
| Number of participants (0.04–0.49 g/kgBW/d) | 1036 | 582 | 1618 |
| Number of participants (0.50–2.06 g/kgBW/d) | 274 | 212 | 486 |
| Total protein intake (g/kg BW/d) (intervention groups) | 1.50 | 1.46 | 1.49 |
| Number of participants (0.79–1.49 g/kgBW/d) | 708 | 393 | 1101 |
| Number of participants (1.50–3.80 g/kgBW/d) | 472 | 311 | 783 |
| Trial periods (weeks) | 15.1 | 33.3 | 22.0 |
| Number of participants (3 weeks to 2.9 months) | 1845 | 719 | 2564 |
| Number of participants (3 months to 2 years) | 595 | 781 | 1376 |
| Habitual training (%) | 13 | 0 | 8 |
| Body part | |||
| Upper body (%) | 64 | 83 | 72 |
| Lower body (%) | 78 | 57 | 70 |
| Contraction type | |||
| Isokinetic (%) | 15 | 14 | 15 |
| Isometric (%) | 37 | 96 | 59 |
| Isotonic (%) | 82 | 13 | 55 |
Data are shown as the mean values weighted by the number of participants
RT resistance training, BW body weight