At the end of the marathon, there is a closing time as the final limit.
If you close the door after six hours, you won’t be able to run and you’ll be locked out of the door.
Correspondingly, when registering for a marathon, there is also an “opening” time, which corresponds to the closing time.
If the closing time is six hours, then the registration will also require the applicant to have the ability to complete the competition within the closing time, and correspondingly require a proof of completion within six hours.
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