Men who are endurance-trained show a significantly higher increase in nerve activity related to blood pressure regulation 120 minutes after eating, compared to men with average fitness, even though...
Mechanism
Synthesis from 1 study
Endurance training makes the brain more responsive to insulin after eating, which turns up the signal to nerves that control blood flow in muscles. This causes more frequent nerve bursts without changing blood pressure, because the brain is simply reacting more strongly to the same amount of...
Most probable mechanism
After eating, insulin levels rise and cross into the brain more efficiently in people who are endurance-trained. Inside the brain, insulin activates specific nerve cells that trigger a stronger signal to the nerves going to muscles, causing more frequent bursts of activity in those nerves — even though blood pressure doesn't change.
Chronic endurance training increases the efficiency of insulin transport across the blood-brain barrier.
Higher insulin concentration in the hypothalamus activates insulin receptors on neurons in key regulatory regions.
Insulin binding triggers intracellular signaling pathways (PI3K and MAPK) that enhance neuronal excitability in hypothalamic circuits controlling sympathetic output.
Activated hypothalamic neurons increase efferent firing of sympathetic nerves projecting to skeletal muscle.
Increased sympathetic nerve firing elevates the frequency and amplitude of MSNA bursts in skeletal muscle vasculature.
Evidence from Studies
Supporting (1)
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Influence of endurance training on central sympathetic outflow to skeletal muscle in response to a mixed meal.
Contradicting (0)
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