Training one limb with low resistance and restricted blood flow can improve strength in the opposite, untrained limb just as much as high-intensity training does.
Mechanism
Synthesis from 1 study
Training one leg—even with light weights and tight bands—makes the brain send stronger signals to the other leg, helping it produce force faster at the very start of movement. This happens without the muscles getting bigger or spinal reflexes changing, just because the brain gets better at turning...
Most probable mechanism
When one leg is trained with either heavy weights or light weights plus restricted blood flow, the brain sends stronger signals to the opposite leg, making its muscles fire more quickly and forcefully at the very start of movement. This happens without changes in spinal reflexes or muscle size, just because the brain becomes better at activating the muscles on the other side.
Unilateral resistance training induces neuroplastic changes in the motor cortex that increase the strength and efficiency of descending neural signals to the contralateral spinal motor circuits.
These enhanced descending signals lead to greater and more synchronous recruitment of motor units in the contralateral muscle during the initial milliseconds of force production.
The increased early-phase muscle activation results in a faster rate of torque development without changes in spinal reflex excitability or muscle size.
Evidence from Studies
Supporting (1)
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Contralateral training effects of low-intensity blood-flow restricted and high-intensity unilateral resistance training
Contradicting (0)
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