Fig. 4
From: Muscles adaptation to aging and training: architectural changes – a randomised trial

Comparison of Regression equations obtained from the muscles of the triceps surae in young (grey) and old (black) groups. Values are relative to maximum anatomical cross sectional area (ACSA) and muscle length. a: Medial gastrocnemius (MG), b: Lateral gastrocnemius (LG), c: Soleus (Sol); * Significant difference between young and old (p < 0.05)