Table 1.
Descriptive Statistics: Means and SEs for Young and Old Female and Male Cohorts
|
Females |
Males |
||||
| Young | Old | Young | Old | ||
| Phenotypic measure | Group differences | (n = 185) | (n = 185) | (n = 191) | (n = 187) |
| Body weight (g) | a s i | 28.19 | 36.30 | 39.30 | 47.20 |
| (0.44) | (0.44) | (0.43) | (0.44) | ||
| Body length (cm) | a s | 9.75 | 10.33 | 10.36 | 10.98 |
| (0.03) | (0.03) | (0.03) | (0.03) | ||
| Body mass index (kg/m2) | a s i | 2.95 | 3.35 | 3.66 | 3.90 |
| (0.03) | (0.03) | (0.03) | (0.03) | ||
| Cohort means adjusted for size covariates (body weight and length) | |||||
| Hind limb rears (#) | a s i | 11.09 | 9.81 | 14.43 | 11.49 |
| (0.56) | (0.56) | (0.64) | (0.68) | ||
| Quadrants entered (#) | s i | 20.05 | 23.32 | 23.83 | 23.99 |
| (0.86) | (0.85) | (0.91) | (0.96) | ||
| Gastrocnemius (mg) | a s i | 118.7 | 111.3 | 153.4 | 135.0 |
| (0.90) | (0.91) | (1.21) | (1.28) | ||
| Soleus (mg) | a s | 8.31 | 7.68 | 10.62 | 9.60 |
| (0.12) | (0.12) | (0.14) | (0.15) | ||
| Extensor digitorum longus (mg) | a s | 9.15 | 9.07 | 11.79 | 10.82 |
| (0.10) | (0.10) | (0.12) | (0.13) | ||
| Tibialis anterior (mg) | a s | 42.74 | 40.99 | 54.14 | 51.12 |
| (0.31) | (0.31) | (0.42) | (0.44) | ||
| Tibia yield load (N) | a i | 11.94 | 11.04 | 14.00 | 11.16 |
| (0.17) | (0.17) | (0.24) | (0.25) | ||
| Tibia ultimate load (N) | a s | 13.66 | 12.01 | 15.94 | 13.65 |
| (0.18) | (0.18) | (0.24) | (0.25) | ||
| Tibia stiffness (N/mm) | a s i | 56.55 | 62.07 | 70.58 | 81.80 |
| (0.90) | (0.90) | (1.40) | (1.48) | ||
| Femur yield load (N) | a s i | 15.80 | 15.23 | 16.49 | 14.40 |
| (0.26) | (0.26) | (0.24) | (0.26) | ||
| Femur ultimate load (N) | a s i | 19.62 | 18.98 | 20.53 | 18.21 |
| (0.30) | (0.30) | (0.26) | (0.27) | ||
| Femur stiffness (N/mm) | a s i | 110.3 | 154.0 | 108.6 | 139.2 |
| (2.7) | (2.7) | (2.3) | (2.4) | ||
Group Differences (p ≤ 0.05) from ANOVA/ANCOVA as a function of age (a), sex (s), and sex by age interactions (i). Shading indicates significant within-sex age differences (p ≤ 0.05).