Table 1.
Phenotypic characterization and muscle weights standardized to tibia length for male and female C57BL/6J mice at middle age (15-month SED), old age (23-month SED), and following 34 weeks of RWE intervention (23-month EXE)
| Male | Female | |||||
|---|---|---|---|---|---|---|
| 15-month SED | 23-month SED | 23-month EXE | 15-month SED | 23-month SED | 23-month EXE | |
| Phenotype characteristics | ||||||
| Abdominal fat pad (% BW) | 1.0 ± 0.3 | 2.8 ± 0.4* | 1.8 ± 0.3 | 0.8 ± 0.1 | 2.0 ± 0.4* | 1.3 ± 0.2 |
| Blood glucose (mmol/L) | 10.7 ± 0.3 | 9.2 ± 0.4 | 8.7 ± 0.5 | 11.6 ± 1.0 | 9.9 ± 0.4* | 9.6 ± 0.3 |
| Tibia length (cm) | 1.80 ± 0.01 | 1.80 ± 0.01 | 1.82 ± 0.2 | 1.82 ± 0.01 | 1.81 ± 0.01 | 1.83 ± 0.01 |
| Heart weight (mg) | 174.6 ± 7.2° | 165.3 ± 6.2° | 187.3 ± 7.0°♦ | 135.4 ± 7.1 | 145.0 ± 5.0 | 169.3 ± 7.0♦ |
| Whole muscle weights | ||||||
| Quadriceps (g)/tibia (cm) | 119.1 ± 3.6°°° | 101.6 ± 2.6*°°° | 112.4 ± 2.9°♦ | 87.7 ± 2.3 | 76.7 ± 2.0* | 84.6 ± 1.6♦ |
| Gastrocnemius (g)/tibia (cm) | 93.8 ± 3.3°°° | 83.1 ± 2.0*°°° | 89.2 ± 2.7°♦ | 67.4 ± 1.3 | 66.2 ± 2.3 | 69.9 ± 1.5 |
| Soleus (g)/tibia (cm) | 5.5 ± 0.3 ° | 4.5 ± 0.2* | 6.6 ± 0.3♦♦♦ | 4.7 ± 0.2 | 4.5 ± 0.2 | 5.7 ± 0.4♦♦♦ |
| TA (g)/tibia (cm) | 28.0 ± 1.7°°° | 24.1 ± 0.7*°°° | 26.5 ± 1.7° | 20.5 ± 1.0 | 18.3 ± 0.3 | 20.1 ± 1.2 |
| EDL (g)/tibia (cm) | 6.8 ± 0.4°°° | 6.3 ± 0.3°°° | 7.3 ± 0.1°♦ | 5.6 ± 0.2 | 4.9 ± 0.2 | 5.9 ± 0.5♦ |
| Triceps (g)/tibia (cm) | 72.6 ± 2.2°°° | 68.2 ± 1.2°°° | 68.5 ± 2.5° | 52.2 ± 1.0 | 52.0 ± 2.3 | 53.2 ± 1.2 |
Values are means ± SEM
EDL extensor digitorum longus, EXE exercise, NS no significance, RWE resistance wheel exercise, SED sedentary, TA tibialis anterior
*Significant difference between 15-month SED within the same sex; *P < 0.05
♦Significant difference between 23-month SED within the same sex; ♦ P < 0.05; ♦♦ P < 0.05; ♦♦♦ P < 0.05
°Significance between male and female mice in the same group; °P < 0.05; °°P < 0.05; °°°P < 0.05