The stretching reflex is a vital mechanism in the human body that helps maintain muscle tone and posture. It is an involuntary response triggered when a muscle is suddenly stretched. This reflex causes the muscle to contract immediately, preventing overstretching and potential injury. For example, when a doctor taps your knee with a reflex hammer, your leg kicks forward due to the stretching reflex. This response is controlled by muscle spindles—sensory receptors within the muscle that detect changes in length. Athletes and physical therapists often consider the stretching reflex when designing warm-up routines, as proper stretching can help manage and optimize this natural response.

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