Racing with a Speed and Distance Device

BY Matt Fitzgerald

Matt Fitzgerald discusses how to effectively use your device during a race.

Run speed and distance devices such as the Timex Ironman Bodylink are useful tools for monitoring, analyzing, and planning your training. But they can also help you race better. Specifically, you can use your speed and distance device to select an appropriate race pace goal and then stick to it. In this short article I will explain how to use your speed and distance device most effectively in races.

Determine Your Goal Pace

You should start every race with a sensible target pace that you hope to sustain more or less from start to finish. The idea is to select the very fastest pace you are capable of sustaining on race day given your current fitness level (or your anticipated fitness level on race day). There are several methods you can use to determine this pace.

If you are an experienced runner, you can compare your times in workouts leading up to races to your times in workouts leading up to one or more past races of the same distance.  Your race time goal should be greater or lesser than your past finishing times by an amount that is commensurate to the difference in workout times. For example, suppose your pace for 1K intervals prior to a past 5K was 3:48, and your finish time in that 5K was 19:09. Your pace in your most recent 1K interval workout was 3:41, so perhaps your goal for the next 5K should be 18:45 or therabouts, which translates to a pace of 6:02 per mile.

If you’re training for a shorter race, you can use a tool called a relaxed time trial to determine an appropriate race goal. If you’re training for a 5K, run 5K on the track at 95 percent effort, determine your pace, and set a race pace goal that’s roughly 5-percent faster. If you’re training for a 10K, do a 10K relaxed time trial. In addition to helping you set a pace goal, relaxed time trials are excellent race-specific workouts.

Obviously, relaxed time trials at the half-marathon and marathon distances would take too much out of you. A better way to select a target pace for these longer races is to run a 10K tune-up race and then use a race time equivalence calculator such as this one to determine an equivalent finish time for the longer race, which will then yield your target pace.  For example, according to the McMillan calculator, a 10K tune-up race time of 31:40 converts to a marathon finish time of 2:28:37.

Figure Out Your Pacing Strategy

Your pacing goal for a given race should not automatically be to run at precisely your target pace from start to finish. The course topography and other conditions may be such that the fastest way to reach the finish line is to run some parts slightly faster than others. For example, the first several miles of the Boston Marathon are downhill, while a tough series of hill climbs lies in wait in the second half. Thus, while it is optimal to run equal first- and second-half splits in a marathon when possible, a more realistic aim in Boston is to run the first half just slightly faster than the second.

If you can’t always run at an even pace from start to finish of a race, you can and should always run at a steady exertion level. In other words, when you encounter a hill climb in a race, you should slow down just enough to maintain the exertion level associated with your target pace on the flats, and when you descend a hill you should speed up by an equivalent amount.

Normalized Graded Pace (NGP) is an exclusive TrainingPeaks WKO+ metric that you can use to develop a sense of how gradient, pace, and exertion level interact. NGP is the 0.0-gradient exertion equivalent of the running pace on any other gradient, up or down. With this tool you can figure out how much to slow down on race climbs and how much to speed up on race descents. Simply run the those hills (or the most similar hills you have access to) in training and determine the actual pace that converts to an NGP that is equivalent to your target race pace. Then run the hills at those associated actual paces in the race.

For example, suppose your target pace for an upcoming half-marathon is 7:30 per mile. In training on that race course’s toughest hill, and then downloading your workout data to TrainingPeaks WKO+, you might find that you must slow down to an actual pace of 8:02 per mile on that hill to maintain an NGP of 7:30 per mile.

Account for Your Unit’s Degree of Accuracy

No speed and distance device is 100-percent accurate. The best ones are very close, but when racing you need your pacing to be perfect. If you start just 2-percent too fast you could bonk before the finish and fail to make your time goal. If you start just 2-percent too slow you will have no chance to make up all of your lost time when you discover your error in the homestretch.

To ensure that your device does not lead you astray in races, try to determine its precise degree of accuracy beforehand. For example, through experience I know that my Garmin Forerunner 305 consistently overestimates my speed by 1 percent. Thus, when I race I mentally add three to four seconds per mile to the pace reading that the display watch gives me.

Use Your Device as a Guide, Not a Crutch

To reach the finish line as quickly as possible, you need to rely on both performance data (time, distance, pace) and somatosensory feedback from within your own body. It is a well-established fact that runners run faster when they run in pursuit of time goals and receive relevant feedback while they run. However, ultimately it’s your body that decides how fast you can go on any given day. After all, if this were not the case, we would always achieve our time goals!

It is important to bear these facts in mind when racing with a speed and distance device. Throughout the race, check your pace as often as necessary to avoid mistakes such as starting at a suicidally fast pace or slowing down in the middle of a longer race due to lose of focus. But don’t use this data as a crutch. If you ever find yourself right on pace in the middle of the race yet feeling either that you could go faster or that you cannot hold that pace all the way to the finish, heed your body’s message and adjust your pace accordingly.

Ignore Heart Rate until After the Race

If your speed and distance device has heart rate monitoring capability, go ahead and wear the chest strap for races, if you wish, but don’t bother paying attention to your heart rate during races. This data will not help you pace yourself more effectively.

After the race, find your average heart rate for the race. You can use this number as a target for future race-intensity workout segments—especially those done in the base phase of training, when you are not yet fit enough to run at your peak race pace. For example, suppose you run a marathon in 3:07 (or 7:09 per mile) and your average heart rate is 157 BPM. Upon resuming training after an off-season break, you may find that you are only able to sustain a pace of 7:17 per mile at a heart of 157 BMP. When performing progression runs and other workouts during the base-building period, use a target of 157 BPM instead of a pace of 7:09 per mile to avoid over-stressing your body.

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Trainingpeaks Author Matt Fitzgerald
About Matt Fitzgerald

Matt Fitzgerald is a journalist, author, coach and runner specializing in the topics of health, fitness, nutrition, and endurance sports training (read more about Matt on his blog). Matt uses TrainingPeaks to train, coach and deliver pre-built training plans for runners including training plans built specifically to be used with a Garmin Forerunner. View Matt’s 80/20 running plans here and his 80/20 triathlon plans here.

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