Neural Adaptations in BFR Training: What Really Changes in Your Muscles?

Effects of 4 weeks of low-load unilateral resistance training, with and without blood flow restriction, on strength, thickness, V wave, and H reflex of the soleus muscle in men.

Colomer-Poveda D, Romero-Arenas S, Vera-Ibáñez A, Viñuela-García M, Márquez G.

Think muscle growth is all about nerve signals? A fascinating study in the European Journal of Applied Physiology challenges some common assumptions about how blood flow restriction training works.

The Big Picture: Researchers investigated whether low-load training with and without blood flow restriction affects not just muscle size and strength, but also the nervous system's role in these improvements.

What They Did: The study followed 22 men divided into three groups:

• BFR with low-load training

• Low-load training without BFR

• Control group (no training)

Training involved:

• 4 weeks of exercise

• 25% of maximum strength

• Three sessions per week

• Four sets per session

Key Findings:

1. Strength Gains:

   • BFR group: 33% increase

   • Regular training: 22% increase

   • Control group: No change

2. Muscle Growth:

   • BFR group: 9.5% thickness increase

   • Regular training: 6.5% thickness increase

   • Control group: No significant change

3. Neural Activity:

   • No significant changes in nerve signals

   • Similar neural patterns across all groups

   • Improvements came from muscle adaptation

What This Means for Practice: These findings suggest that:

• BFR enhances muscle growth without neural changes

• Strength gains come primarily from muscle adaptation

• Both methods work, but BFR shows greater results

The Bottom Line: Blood flow restriction training appears to work through direct muscle adaptation rather than neural changes, producing superior results to regular low-load training while using the same light weights.

Link to original research