Utilize the information you get from your power meter to know when to begin your sprint and how long you'll last.
With the advent of affordable and accurate power meters, wattage is all the rage. Although power meters have been around for years, they're finally starting to become standard equipment for competitive and recreational cyclists alike.
Naturally (and unfortunately) simply having a power meter won't make you stronger, but when used wisely you can make massive performance gains.
Many things can be looked at with a power meter, and with the manufacturers packing so many features and graphs into the software it can become quite confusing. Let me simplify this for you.
It doesn't matter how much power you can generate in a sprint if you're not there to bump elbows with the lead bunch and participate. Sit up all night and sharpen your elbows as much as you want, but what's going to get you sprinting with the lead bunch is your maximum sustainable power. Athletes with a high sustainable power and a good head win races, plain and simple.
Preparing for the Split
In many amateur races a split in the field occurs long before the sprint is in sight. This split is often dictated by terrain, weather conditions or, more commonly, a grueling pace set by strong teams and individual riders. This split is the most important part of the race for many riders in the peloton.
Generally, the riders that make the split will not only have the maximum sustainable power required to stay with the lead bunch but also the ability to repeat this effort as the breakaway matures. This is the point when the data you collected with your power meter can become extremely valuable.
Power meters and the data they collect are equally useful in racing as in training. Outside of knowing what level of power you're able to produce and how long you can sustain that power before you fall apart, the data collected can provide invaluable information for directing your training.
This is particularly true when it comes to increasing your maximum sustainable power (the power you need to make it into the breakaway or through the winning selection), your maximum repeatable power (the power you need to handle or initiate surges) and your sprint power.
The first step is dissecting files from races or strenuous group rides and noting the power required at key points—splits, hills, breaks, sprints, etc.—or, more generally, the physiological demands of the event. These demands are relatively easy to isolate if you're placing markers at key points while racing. This is assuming you can see straight enough to press the correct buttons.
What you're looking for in past files are the areas where you ran into difficulty or where the split occurred. Early on in the race, these splits will usually be caused by a consistent, high pace rather than the explosive efforts required for smaller breakaways, so what you're looking for in the files are the longer periods of higher power outputs.
Identify the power you needed to produce while you were holding the pace, then make note of how long you were able to hold that power before failing to make the split. If you survived the first split but fell off the pace in the second or even third surge, then you need to be looking at the repeatability of the efforts as well as the sustainable power required in each effort.
Increasing Maximum Sustainable Power
In order to increase the sustainable power you can produce as well as your ability to repeat those efforts you first need to identify your lactate threshold (LT) power. This can be obtained through laboratory testing or through a couple three-mile time trial efforts. Most experienced cyclists can complete a three-mile time trial at an average power that's about ten percent above their lactate threshold power.