The Science Behind Time Trial Pacing
To define pacing in cycling is simple, it’s the rate at which you complete a course. Every course has a pace whether or not you’re aware or in control of your pace. A mindful pacing plan based off the course conditions, your personal power curve, and physiological knowledge can leave you minutes ahead of your competition.
There’s a couple common mistakes I see when people are attempting, and failing, at making proper time trial pacing. The most common mistake is just not having pacing. Every time trial you do, and every time you’re in a spot in a race that you’re alone, you should be thoughtful and intentional with your pacing. This article will have some tips and tricks and will take you through a practical example of pacing creation. If you choose to do this on your own, work with your coach on your finished pacing product or compare to Best Bike Split.
The second common mistake in choosing a pace for time trials is what I like to call “The hero’s approach.” The hero’s approach is when you look at the KOM time for a TT on strava or look at the time of a past winner and try to ride to that. If you’re in contention to win, it’s good to know what you have to do in order to win, but in general you’re better off looking at your ability and riding to the very edge or just beyond that rather than attempting to pace off others in an individual ride or time trial. Strava can be a great tool but it can also lead you astray as you do not know the conditions that the KOM time was completed.
Steps To Creating Good Pacing:
- Look at the course and estimate a finish time based on the rider we are creating pacing for. Strava is a great tool for this if the TT has happened before. Otherwise we need to use WKO and Training Peaks to estimate a power for the distance and climbing. This is a very tricky step.
- Look at the course profile with estimated time and look at a flat peak power estimate for the rider based on the ride time.
- Add in specific power numbers over threshold or recovery based on the specific climbs or wind sections of the course. Any undulation in a course changes a pacing scale from flat pacing to anaerobic sections with assumed recovery times.
Let’s Do An Example. Here’s A Time Trial Course – 2019 USPRO Nationals TT
You can tell from this profile it’s 2 laps of the same course. Profiles in general, especially shorter courses will look like steep walls of climbs but when you look at the axis on the right the climbs are only a few hundred feet. Significant for pacing but make sure you’re looking at the length and grades of the climbs.
Here’s the power profile of the athlete. We’re trying to write out pacing to give this athlete the fastest time across this course.
Now For The “Strava Coaching.”
Here’s a link to the Pro Nats TT segment activity by a competitor not our athlete.
Use all the tools at your disposal. In this case we have last years TT results in Strava. Power analysis of other riders etc. If we don’t have this for a new TT course it’s going to be just off of estimations based on power and speed. From this file of a rider a similar size to our athlete, her time was 33:17, was good for 9th place. Now we have a baseline to look at our athletes numbers for 31 – 33 minutes. Its a loop and out and back so there’s not much major wind exposure in any one direction.
Based on the MMP curve from WKO we’re looking at above, this graph is also in TP but is less detailed. Our athlete’s 30 -33 minute max historical power from the last 365 days is 290 watts. That 290 watt effort is from another TT so pretty accurate from the TT bike and is the same wattage from 29 minutes to 34 minutes so we can assume that it’s a sustainable power if the TT should be a minutes slower or minute faster. If we’re going to smash that power record in the goal event it will be safer to hit those numbers at the end.
Now we get more detailed, working in some physiology principles and customizing to this course. If you accumulate acid with anaerobic effort, you have to recover to buffer this acid. The goal in pacing is to do the max power possible across the course. If we spike acid too early then we go slower as there is no real recovery time in a well paced TT. If we’re working in physics and wind resistance, we will go faster if we apply more power on climbs. MAJOR PRINCIPLE FOR PACING IN CYCLING – wind resistance is exponential, the faster you go the more resistance. If we want to have the fastest time, we will do higher powers on climbs as the wind resistance is less creating a higher speed gain from more power on the climbs. Once we’re over 40 mph you may as well coast and super tuck to go fast while recovering. We will inject pace on the climbs for maximum speed and lowest course time. We will need to figure out what the athlete can recover from to not go too hard on the climbs for the amount of “recovery” we can get on what descents there are on course.
So we know that our athlete’s time will be between 30 mins and 32 minutes from the other Strava files. We can assume that our 290 watt 30 minute effort will be within 3 percent of what our athlete will do in the TT. So to get the fastest time, will write the pacing going over 290 watts on the climbs and slightly under threshold on the descent sections over 40MPH or where there are turns (not many). This TT also has 2-180 degree turnarounds per lap so we will have to pace a controlled but strong acceleration out of those turns.
Here’s The Finished Time Trial Pacing Product:
- Start – sprint out the gate for 10 seconds at 80% max sprints, get into the aero bars ASAP as it’s downhill
- Mile 0-2.5 – 280 watts – 100% FTP
- Mile 2.5-3.5 290-310 watts – 105-110% FTP
- Mile 3.5 – 4.5 – 270 – 90% FTP
- Mile 4.5-5.3 – steepest climb – 295-315 watts 110-115% FTP
- Mile 5.3-5.7 recover fast descent under 280 watts
- Mile 5.7-6 ramp quick at bottom of climb – 300-325 watts
- Mile 6-6.7 – recover, tuck and pedal, 265-275 watts 90% FTP
- Mile 6.7 – 9.8 (into lap 2) 280 watts – 100% FTP
- Mile 9.8 – 10.8 – 290-310 watts – 105-110% FTP
- Mile 10.8 – 11.7 – 270 – 90% FTP
- Mile 11.7- 12.6 – final steep climb, dump the tank – 300-330 watts 115-120% FTP
- Mile 12.6 – 13 – quick recovery
- Mile 13-13.3 – Ramp into final kickr – 320-330 watts 120% FTP
- Mile 13.3 – finish 290- max all out to finish at 14.6 miles. Sprint at 300 meters all out.
In this TT with multiple 180 degree turn-arounds, I don’t create pacing to turn arounds but let the rider know that there’s turn arounds and to make sure to go max speed and late brake into the turn around, take a good line through the 180 and accelerate with purpose but not over 90% max sprint.
This pacing sheet is way too complicated to be taped to the top tube of the TT bike. The rider should take this sheet and visualize the times and some basic numbers on course. Over threshold on the climbs, where the steepest portions are, where the tops of the climbs are, and know to go under FTP for the brief descents. This can be chopped down a bit to the major climbs for pacing but it’s good to have all the math down and to calculate the average intensity factor so that we aren’t knowingly overshooting. No one should be able to do 1.3IF for 32 minutes so make sure your math works out.
The riders outcome was very close to ideal for pacing. The hills and ramps were spot on and the rider felt at max at the end of the TT so it was not under paced. The only feedback from the file was to go a bit harder over the top of the climbs instead of to the top. Going hard well over the top of the climb to the descent drastically increases descent speed whereas stalling on the top lengthens time all around.
The facts are this pacing was built on the riders PD curve, the rider averaged 1.03 IF or 103% of FTP for 32 minutes and this time was good for 7th at the USA Pro Women’s Time Trial. That’s successful pacing.
A special thank you to SnowyMountain Photography for permission to use the featured photo.
Zack Allison earned his bachelor’s degree in Exercise Science at Colorado State University. As part of his education, he participated in many hands on exercise science practicum and internships, coaching many types of athletes, specifically cyclists.
Zack’s affinity for cycling started at the early age of 14 racing on the east coast. He quickly moved up the amateur ranks to race on the elite national circuit. This level of competition sparked his interest in exercise science, taking him to Colorado State University. While racing for his alma-mater and on various amateur teams he saw many podiums at the Collegiate Championships and Pro/Am events. Zack is currently living in Fort Collins, Colorado and has raced for Elevate Pro Cycling and currently races for Clif Bar.
Growing up with great mentors and coaches, Zack has a goal of paying it forward. He hopes to use his education and racing experience to bring success to Source Endurance and his clients.