The Claim
In healthy young active men, performing 45 minutes of low-intensity walking after an overnight fast increases cortisol levels and decreases the testosterone-to-cortisol ratio during recovery compared to performing the same exercise after consuming a standardized meal, indicating a more catabolic hormonal environment.
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.
In healthy young active men, walking for 45 minutes after fasting raises cortisol and lowers the testosterone-to-cortisol ratio during recovery compared to walking after eating a standardized meal.
See the scientific wording
In healthy young active men, performing 45 minutes of low-intensity walking after an overnight fast results in significantly higher cortisol levels and a lower testosterone-to-cortisol ratio during recovery compared to performing the same exercise after consuming a standardized meal, suggesting a more catabolic hormonal environment that may不利于 muscle preservation.
When a person hasn't eaten overnight, their blood sugar drops, which signals the brain to release stress hormones that increase cortisol. This cortisol breaks down muscle protein and blocks muscle-building signals. During light exercise, this effect is stronger than when food was eaten beforehand, because eating triggers insulin that lowers blood sugar during activity and reduces the stress response. The result is more cortisol and less muscle protection after exercise when fasting.
What the research says
1 studyStudy: Cardiorespiratory, enzymatic and hormonal responses during and after walking while fasting
When healthy young men walk gently after not eating all night, their bodies release more stress hormone (cortisol) and less of the balance between stress and muscle-building hormones compared to when they walk after eating. This suggests their bodies are in a state that’s less friendly to keeping muscle.
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.