Table 1.
Demographic data and muscle properties in the two age groups
| Variable | Young (N = 12) | Old (N = 12) | ||
|---|---|---|---|---|
| Demographic data | ||||
| Age (years) | 23.33 (3.75) | 67.92 (2.11) | ||
| Gender (male/female) | 5/7 | 6/6 | ||
| Length (m) | 1.76 (0.11) | 1.70 (0.05) | ||
| Mass (kg) | 70.83 (11.46) | 70.08 (13.47) | ||
| Muscle architecture and echo intensity data | ||||
| Gastrocnemius medialis | ||||
| PA rest (°) | 18.71 (3.12) | 16.16 (2.91) | ||
| PA contraction (°) | 21.77 (3.45) | 19.07 (5.17) | ||
| FL rest (cm) | 5.12 (0.75) | 6.53 (2.91) | ||
| FL contraction (cm) | 4.51 (1.03) | 5.34 (1.89) | ||
| MT rest (cm) | 1.63 (0.28) | 1.61 (0.29) | ||
| MT contraction (cm) | 1.72 (0.42) | 1.64 (0.30) | ||
| Tibialis anterior | ||||
| PA rest (°) | 9.82 (2.23) | 11.81 (2.51) | ||
| PA contraction (°) | 13.10 (3.55) | 14.88 (3.28) | ||
| FL rest (cm) | 6.26 (0.83) | 6.51 (1.14) | ||
| FL contraction (cm) | 5.44 (0.90) | 5.66 (0.91) | ||
| MT rest (cm) | 1.04 (0.21) | 1.16 (0.17) | ||
| MT contraction (cm) | 1.17 (0.27) | 1.28 (0.18) | ||
| Vastus lateralis | ||||
| PA rest (°) | 13.30 (1.92) | 10.60 (2.79) | ||
| PA contraction (°) | 12.72 (3.30) | 9.87 (2.52) | ||
| FL rest (cm) | 12.14 (2.12) | 10.96 (3.81) | ||
| FL contraction (cm) | 11.18 (2.53) | 11.90 (3.75) | ||
| MT rest (cm) | 2.71 (0.40) | 1.98 (0.34) | ||
| MT contraction (cm) | 2.57 (0.34) | 2.09 (0.23) | ||
| MVF data (N) | ||||
| Gastrocnemius medialis | 538.18 (259.73) | 421.33 (153.97) | ||
| Tibialis anterior | 163.83 (66.59) | 170.17 (54.98) | ||
| Vastus lateralis | 441.55 (152.80) | 309.83 (102.03) | ||
Data are expressed as mean (SD)
EI echo intensity, PA pennation angle, FL fascicle length, MT muscle thickness, MVF maximum voluntary force