The Claim
Over a 12-week resistance training program, soleus muscle hypertrophy is statistically similar regardless of whether the knee joint is positioned in flexion (seated) or extension (standing), indicating that soleus growth is less dependent on knee joint angle compared to the biarticular gastrocnemius.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
Doing leg exercises with your knees bent or straight builds the deep calf muscle about the same amount over 12 weeks. This means your deep calf muscle doesn't really care whether your knee is bent or straight when you're lifting weights.
See the scientific wording
The soleus muscle exhibits similar hypertrophy regardless of knee joint position during resistance training, indicating that its growth is less dependent on muscle length at the knee compared to the biarticular gastrocnemius. Over 12 weeks of matched resistance training, soleus volume increased by 2.1% in the standing condition and 2.9% in the seated condition, with no statistically significant difference between positions.
What the research says
1 studyStudy: Triceps surae muscle hypertrophy is greater after standing versus seated calf-raise training
The study found that doing calf raises while standing or sitting resulted in the same amount of muscle growth for the soleus muscle over 12 weeks. This shows that the soleus grows equally well whether your knee is straight or bent.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.