Tapering must start at least one month or three weeks before the actual marathon. During this time you are supposed to run for the complete mileage which you are supposed to cover during the race. Make sure that you run at your full potential and time yourself so that you know where you stand.
With three weeks remaining in the marathon, you are supposed to cut down your mileage to eighty percent of the actual race. You are trying to temper things down, but don’t try to reduce the speed at which you are running. You must time yourself in this case as well and know where you stand.
After training at eighty percent for the whole week, cut your mileage down to fifty to seventy-five percent with two weeks remaining in the race. Even during this time you must maintain peak fitness and make sure that you are timing yourself. Keep running at your full potential.
With a single week remaining in the marathon, cut your mileage to one-third of the normal routine. During this time you must keep running at the same rate.
When you enter the week during which the marathon is supposed to take place, do not run at your best speed. In fact, try to jog lightly. Make sure you do keep sprinting in parts, but don’t try to overstretch your body right before the race. During the last few days simply jog for most of your time, and sprint for a little while. If you don’t sprint at all, you might totally change your stride.