How tapering maximizes your potential on marathon day

The taper is an essential aspect of training that many new runners need to remember to incorporate into their training program. Tapering means reducing your training load before a competition to optimize performance on race day. It's the rest period before race day to reduce the effects of muscle fatigue brought on by months of rigorous training.

During marathon training, muscle power diminishes, stores of glycogen (a form of glucose) deplete and overall muscle fatigue accumulates. The tapering period minimizes the adverse effects of a long-distance training schedule, so your muscles will be fresh and fatigue-free on race day, significantly reducing your injury risk.

What are the benefits of tapering?

Adding tapering to your training can:

• Bolster your immune system to lower your risk of being sick on race day
• Improve your running economy, which is the oxygen your body needs to run at a given pace
• Replenish glycogen stores so that you have the necessary amount of fuel stored in your body on race day
• Repair damaged muscle tissue, which restores muscle fibers and allows them to work their best when you need them the most.
• Reduce the psychological stresses of training, which will help you be mentally strong on race day
• Improve sleep quality so that you get the rest you need leading up to the race

What are the guidelines for tapering?

People often wonder how to define "rest" during tapering and how to make sure it's helping performance and not hurting it.

A meta-analysis of 27 studies published in the journal Medicine & Science in Sports & Exercise showed that a tapering strategy most likely to give you significant performance improvements for two weeks, where the training volume is progressively decreased by 41–60% without modifying the training intensity or frequency.

This means altering your training volume by decreasing only the length of each training session. The most common way is to reduce the number of miles run per session in the two to three weeks leading up to race day, depending on the length of the race.

How do you calculate your rate of progression during the taper?

For example, if you're running six miles two or three times a week during your peak training period, you'll want to drop that mileage by 41-60%, approximately 2.5 to 3.5 miles.

Here's how to calculate this:

• 41% of 6 miles: 6x0.41=2.46, so 6-2.46=3.54 miles
• 60% of 6 miles: 6x0.60=3.6, so 6-3.6=2.4 miles

One way to do this is to run three to four miles per run the first week and two to three miles per run the second week.

Remember that the other key piece of the findings is to keep the intensity or frequency of your training the same during the taper. So, if you're running four times per week during your peak training, you should continue to run four times per week. If you're training at a 10-minute per mile pace, you should continue to train at that pace during the taper.

The taper strategy will vary based on the length of your race. The longer the race, the longer the taper.

The taper lengths for the most popular race distances are:

• Marathon — 19 to 22 days
• 15K race — 11 to 14 days
• 5K or 10K race — seven to 10 days

This chart shows suggested taper percentages based on some common race distances:

Plan to taper only for your key or peak races. If you taper for every race, you'll miss the key physical conditioning needed to get into optimal shape.

Remember to also strive for quality sleep and good nutrition during the taper and the week of the race. Both are needed to promote physical recovery and allow your muscles to repair and rebuild.

Leslie Grommersch, Kimberly Olsen and Desiree Essler are physical therapists in Mankato, Minnesota.