On Monday I began my two-week taper for the California International Marathon. I made it! What a relief. I will run only 44 total miles this week and 22 miles next week (not including the marathon), compared to as much as 80 miles in preceding weeks, so my chances of getting injured are small.
If you're wondering why I consider merely "surviving" until the taper period such a cause for celebration, I'll tell you. Six years ago I was in the best shape of my life while training for the Boston Marathon. I set huge PR's at 5K and the half-marathon and was confident of running somewhere around 2:36 or 2:37 in Boston. Then, less than three weeks before race day, I developed a bad case of hip flexor tendonitis that forced me to skip the race. I was very disappointed, but my disappointment would have been 10 times greater if I had known that this injury would be only the first in a long sequence of breakdowns that would prevent me from running another marathon in peak shape until now. So just by making it to the starting line of the California International Marathon in one piece, I will remove a six-year-old monkey from my back.
Here's how I like to taper for marathons:
Two weeks before race day I run 20 miles. Endurance is the facet of running fitness that always comes hardest to me, so I like to have a farily recent 20-miler in my legs when I start a marathon.
I maintain the same basic weekly workout structure during the taper as I do during the peak training period, but all of the distances are reduced. I do two high-intensity workouts during the week and a long run on the weekend. This week's key workouts will be roughly 30% shorter than in the preceding week. Next week they will be 50-75% shorter. It's important not to completely eliminate high-intensity running from your training during the taper period, because tapering is not strictly about resting up for your marathon--it's also about priming your body for peak performance.
I am continuing to cross-train (slideboarding) and strength train this week, but I will eliminate that stuff next week.
Some runners like to rest on the day before their marathon, but I prefer to do a very short run (2-3 miles) plus a few strides to keep myself from bouncing off the walls. Also, even in training I've observed that I almost always run better in a hard workout when I run easy the previous day instead of not at all.
My final long run, performed one week before race day, will be a 15-miler with the last 3 miles at marathon pace. I try to do at least a mile of marathon-pace running each day throughout the taper period, because I want my body and mind to be as comfortable as possible at that pace.