Respuesta :
You would not want to over work your body, you should start slow, then work your way up. If you work to hard at the beginning, you will get cramps, and you will probably be dehydrated. It is important to start slow, And improve slowly. That should give you the answer.
During the three weeks before an event the best idea would be to taper down your training during the last two weeks. This will allow you enough time for recuperation but you will still stay active and fit during this time.