Table 2.
Summary of cross-sectional studies of changing skeletal muscle mass, comparing between groups within the aged population.
| Study | Technique | Estimate | Sex | Young (years) | Aged (years) | n | Change | % Change | % Change/year |
|---|---|---|---|---|---|---|---|---|---|
| Novak (1972) | Total body potassium | Fat free mass | M | 55–65 | 65–85 | 42, 18 | −6.5 kg | −12 | |
| Cell mass | 55–65 | 65–85 | 42, 18 | −3.6 kg | −12 | ||||
| Fat free mass | F | 55–65 | 65–85 | 54, 13 | −0.8 kg | −2 | |||
| Cell mass | 55–65 | 65–85 | 54, 13 | −0.4 kg | −2 | ||||
| Tzankoff and Norris (1977) | 24 h urinary creatinine excretion | Muscle mass | M | 80 | 90 | 103, 12 | −220 mg/24 h | −18 | −1.8 |
| Cohn et al. (1980) | Total body nitrogen (prompt gamma neutron-activation technique) | SMM | M | 60–69 | 70–79 | 10, 9 | −4 kg | −23 | |
| F | 60–69 | 70–79 | 14, 8 | −0.9 kg | −13 | ||||
| Lexell et al. (1988) | Cadaveric dissection | Vastus lateralis CSA | M | 73 ± 3 | 82 ± 1 | 9, 8 | −624 mm2 | −23 | −2.6 |
| Frontera et al. (1991) | Hydrostatic weighing | Fat free mass | M | 50.5 ± 2.8 | 68.5 ± 2.8 | 24, 34 | −4.8 kg | −8.0 | −0.43 |
| F | 50.2 ± 2.6 | 69.0 ± 3.8 | 28, 34 | −4.3 kg | −11 | −0.58 | |||
| 24 h urinary creatinine excretion | Muscle mass | M | 50.5 ± 2.8 | 68.5 ± 2.8 | 17, 29 | −2.7 kg | −9.7 | −0.52 | |
| F | 50.2 ± 2.6 | 69.0 ± 3.8 | 19, 20 | −3.5 kg | −19 | −1 | |||
| Baumgartner et al. (1995) | Dual-energy X-ray absorptiometry | Appendicular SMM | M | 60–70 | >80 | 17, 32 | −2.9 kg | −12 | |
| F | 60–70 | >80 | 50, 56 | −1.6 kg | −10 | ||||
| Fat free mass | M | 60–70 | >80 | 17, 32 | −4.8 kg | −8.2 | |||
| F | 60–70 | >80 | 50, 56 | −2.7 kg | −6.8 | ||||
| Anthropometrics | Bone free mid-arm muscle CSA | M | 60–70 | >80 | 17, 32 | −7.0 cm2 | −13 | ||
| F | 60–70 | >80 | 50, 56 | +0.6 cm2 | +1.7 | ||||
| Janssen et al. (2000) | Magnetic resonance imaging | SMM | M | 60–69 | >70 | 14, 11 | −0.4 kg | −2.2 | |
| Lower body SMM | 60–69 | >70 | 14, 11 | − | −25 | ||||
| Upper body SMM | 60–69 | >70 | 14, 11 | − | −5.6 | ||||
| SMM | F | 60–69 | >70 | 11, 19 | −0.4 kg | −2.2 | |||
| Lower body SMM | 60–69 | >70 | 11, 19 | −0.8 kg | −7.6 | ||||
| Upper body SMM | 60–69 | >70 | 11, 19 | +0.2 kg | +2.7 | ||||
| Kyle et al. (2001) | Dual-energy X-ray absorptiometry | M | 60–69 | 70–79 | 25, 40 | −0.5 kg | −2.1 | ||
| 70–79 | >80 | 40, 26 | −1.7 kg | −7.2 | |||||
| F | 60–69 | 70–79 | 22, 48 | −0.3 kg | −1.8 | ||||
| 70–79 | >80 | 48, 30 | −0.7 kg | −4.2 | |||||
| Wroblewski et al. (2011) | Air displacement plethysmography and MRI in high-level recreational athletes | SMM | M | 65.4 ± 2.2 | 76.3 ± 3.3 | 5, 5 | −3.2 kg | −5.6 | −0.51 |
| F | 65.0 ± 3.0 | 74.8 ± 3.7 | 5, 5 | −2.7 kg | −6.9 | −0.7 |