Intelligent and Comprehensive Training for Distance Runners


Like most Running Times readers, you no doubt spend countless hours training through all of mother nature’s extremes. As a dedicated distance runner, you know all about intervals, tempo runs, and long runs, and how blissfully tired training can leave you. Training provides long-term improvements in fitness but produces short-term fatigue. The challenge leading up to an important race is to find the optimal balance between training to get into the best possible racing shape and resting to eliminate the fatigue (both physical and mental) of training.

To achieve your best when it counts, you can only afford to do a full taper before a few key races each year. If you race frequently and were to taper thoroughly for each race, you would have little time left for hard training. So, some races you must just “train through.” But for the big ones, perhaps 2 to 4 races per year, you will want to pull out all the stops to achieve your best possible performance. That is when you need a well-planned taper.

A recent paper published in the International Journal of Sports Medicine reviewed over 50 scientific studies on tapering to find out whether tapering actually improves performance, and how to go about it. The review found that there is no question that tapering works. Various studies found improvements in performance of between 2% and 8% when athletes taper their training before competition. Most studies found an improvement of about 3%, which translates to over 5 minutes if you are a 3 hour marathoner or over a minute if you race 10 km in 40 minutes. But, what is the most effective way to cut back your training before an important race? Let’s take a look at how to design the optimal pre-race taper.

How long should you taper?

Several studies investigating the relationship between racing performance and taper duration concluded that the optimal length of taper is from 7 days to 3 weeks. The optimal amount of time for you to taper depends on both the distance you will be racing and how hard you have been training. Too short a taper will leave you tired on race day, while tapering for too long will eventually lead to a loss of fitness. When you consider that any one workout can give you far less than a 1% improvement in fitness but that a well-designed taper can provide a much larger improvement in race performance, it is probably wise to err on the side of tapering too much rather than not enough. The following table shows the best numbers of days to taper for the most popular race distances.

Race Distance# Days to taper
15 km to ½ Marathon11-14
5 km to 10 km7-10

How should you reduce your training to improve racing performance?

The scientific evidence clearly indicates that the key to effective tapering is to substantially cut back your mileage, but to maintain the intensity of your training. Reducing the amount that you run has the greatest impact on reducing accumulated fatigue to improve your racing performance. Once again, how much to reduce your mileage depends on your current training volume and the distance you will race. Although one study suggests reducing mileage by up to 85%, the optimal amount to reduce training is still open to debate. Guidelines for cutting back your mileage, based on both research and anecdotal evidence, are presented below. For example, a marathoner would reduce her mileage by 20% the 3rd week before the race, by 40% the following week, and by 60% on race week.

Amount to reduce mileage before race

Race Distance3rd Week before Race2nd Week before RaceRace Week
15 km to ½ Marathon0%30%50%
5 km to 10 km0%20%50%

(This column originally appeared in Running Times Magazine.)