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Changes in muscle architecture induced by low load blood flow restricted training
Juan Martín-Hernández1, P J Marín, H Menéndez
1Miguel de Cervantes European University Faculty of Health Sciences C/Padre Julio Chevalier, 2 47012 Valladolid Spain ASPAYM Castilla y León Foundation Research Centre on Physical Disability Valladolid Spain.
Acta Physiologica Hungarica
|September 10, 2013
Summary
Blood flow restricted training (BFRT) and high-intensity training (HIT) induce different muscle structural changes. BFRT may involve acute muscle cell swelling, contributing to hypertrophy, while HIT shows greater pennation angle increases.
Area of Science:
- Exercise Physiology
- Muscle Physiology
- Biomechanics
Background:
- Blood flow restricted training (BFRT) and high-intensity training (HIT) are popular exercise modalities.
- The underlying structural mechanisms of BFRT and HIT remain incompletely understood.
- Investigating acute muscle architectural changes can elucidate training-specific adaptations.
Purpose of the Study:
- To examine acute muscle architecture variations after different volumes of BFRT.
- To compare these BFRT-induced changes with those resulting from HIT.
- To explore potential differences in structural responses between BFRT and HIT.
Main Methods:
- Thirty-five young men were divided into low-volume BFRT, high-volume BFRT, and HIT groups.
- Subjects performed bilateral leg extensions using 20% 1RM (BFRT) or 85% 1RM (HIT).
- Muscle thickness and pennation angle of rectus femoris and vastus lateralis were measured via ultrasound before and after exercise.
Main Results:
- All groups exhibited significant increases in rectus femoris and vastus lateralis muscle thickness.
- HIT resulted in significantly larger increases in pennation angle compared to both BFRT LV and BFRT HV.
- These findings suggest distinct acute structural adaptations between BFRT and HIT.
Conclusions:
- Acute muscle cell swelling may contribute to BFRT-induced muscle hypertrophy.
- The study provides evidence for differing structural responses to BFRT and HIT.
- These insights can inform exercise prescription and understanding of training adaptations.
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