How to Pace Your Bike Ride

By Arnie Baker

Pacing on a bike requires self-knowledge and self-control. Pacing may be required when what will limit your performance later does not limit you now. Pacing means riding more slowly at the beginning so that you can go faster at the end. Pacing also means riding more slowly at the beginning so that you can reach the end.

Years ago, runners used to run the mile by starting out almost as fast as they could go. They invariably pooped out at the end. Roger Bannister broke the four-minute barrier for the mile back in the 1950s by planning on running each quarter mile in just under one minute. That planning allowed him to become one of the most famous athletes of all time.

Why Pace Yourself on a Bike?

Because You’ll Finish Faster. Figuring out at what pace you should ride is crucial to great performance in events where the aim is to cover a set distance in the shortest time. This is an essential strategy in track and road time trial events. It’s also very important in cross-country mountain biking. In mass-start cycling events where drafting and tactics play important roles, pacing is a less important component of racing success—but even here, it often makes or breaks a race.

Pacing commonly improves finishing times in such events by 1% to 3%. Very fast starts may worsen finishing times even more.

At many levels of competition there are often very small differences between winning and losing. At the highest levels—the Olympic Games or World Championships—the margin between the glory of a top-three medal and anonymity is often less than 1%.

The difference between going out too hard and pacing yourself well can cost 10 seconds in a 3–K track event, a minute in 10-mile road time trial, and several minutes in a pro cross-country mountain bike race. In mass start events, a lack of pacing can drop a rider who otherwise might win.

Because You’ll Finish, Period! In all-day century and ultra-distance events pacing can play an even greater role. Finishing such events may not even be possible for some participants without pacing.

Sooner or Later, We All Slow Down

Whether you plan on pacing or not, sooner or later, we all slow down. The question is, is it planned? What strategy provides the best chance of finishing? What strategy provides the best finishing time? In a group, or mass start event, what strategy gives the best place finish?

Why Pacing Works

Pacing works because you ration resources that will be needed later, now. Common resources are fuel (usually glycogen), fluids, and heat regulation.

A simplistic explanation of the pacing principle may be the following:

• Go out too slowly and you never have the time to catch up.
• Go out too fast and you run out of energy.
• Go out too fast and your lactic acid levels zoom up too quickly.

It is easier to tolerate high lactic acid levels for short periods of time rather than longer ones.

If high lactic acid levels must be endured, it is easier to tolerate them at the end rather than at the beginning of a race.

Psychologically, the natural tendency of many athletes is to get excited at big competitions and go out too hard. By consciously backing off just a little this risk is reduced. Build to a crescendo rather than start with a bang and fizzle.

There are other benefits to pacing. For example, in a longer event, starting out more slowly will allow you to drink and eat more easily, and so have more energy for the end of the ride

Why Cyclists Slow Down

There are a number of physiological reasons why we slow down: The main reason is that we run out of fuel energy. Dehydration, overheating, and muscle and neuro-hormonal fatigue can also contribute.

1. Dehydration

Consider dehydration in ultra-endurance cyclists as an example why pacing is required:

Suppose an athlete can work reasonably well until 3% dehydrated. Suppose at 6% dehydration health is threatened. Suppose an athlete weighs 140 pounds. Suppose it is a hot and humid day. Suppose working hard, an athlete loses 2.5 quarts (5 pounds) of fluids per hour. Suppose working moderately an athlete loses 1 quart per hour. Suppose the maximum rate of fluid intake is 1.5 quarts per hour. After two hours of hard work, the athlete will be performance impaired. After four hours, general health will be threatened.

The only options are to slow down early (pace) or stop when fatigued or exhausted. Pacing results in a higher overall speed.

2. Fuel Energy

Efforts up to about 10 seconds can be performed “all-out.” Pacing allows efforts of all other lengths to apportion higher-energy producing fuels over longer periods. Pacing results in overall total work and better overall times.

Fuel energy exists in several forms:

Anaerobic energy fuel sources include ATP, which supplies energy for just a few seconds, and CP—creatine phosphate, which helps supply energy for up to 30 seconds.

Aerobic energy fuel sources include carbohydrates and fats.

Glycogen, a form of carbohydrate stored in muscle, allows prolonged work at relatively high energy levels, associated with high heart rates. We are able to store a maximum of only about 2,000 calories of glycogen. After that stored glycogen runs out, we’re basically burning stored fat.

That may sound great to those trying to lose weight, but it means that you can’t ride hard and that you generally feel terrible. Regardless of how hard you ride, you’ll burn about the same amount of fat. At higher intensities you burn carbohydrates as well.

Running out of glycogen means we operate at less than 60% of maximum heart rate. That’s what happens to ultra-distance cyclists after their first 24 hours of competition.

A 25-mile time trial, performed at 92+% of maximum heart rate, may exhaust almost all of our glycogen. A two-hour mountain bike race certainly will. It’s simply not possible to continue at a pace of 90% of maximum heart rate for more than about two hours—one runs out of glycogen.

Glycogen is also stored in the liver. Liver glycogen helps keep the blood sugar level up, which can help spare the glycogen in the muscles. When the muscle glycogen is gone, blood sugar can be converted to useful energy, but not as efficiently.

By maintaining blood sugar with the ingestion of fuels—sugary drinks or carbohydrate solids—we can spare our stored glycogen and ride strongly longer. Consuming calories while riding will allow you to ride comfortably for many more hours than is otherwise possible.

3. Temperature Regulation

On hot and humid days, athletes may need to reduce workload in order to keep from overheating.

Overheating not only reduces power output, it can risk heat cramps, heat exhaustion, and heat stroke. Overweight athletes are more subject to overheating.

Athletes occasionally pace up long climbs in order to keep their clothes dry and so prevent wind-chill from contributing to hypothermia on subsequent descents.

Neuromuscular (Skill) Control

Racing all-out to the top of a climb is frequently a poor tactic for mountain bike racers. Exhaustion at the top of climbs contributes to loss of neuromuscular control and overbraking on descents—resulting in slower overall times.

Heart Rate on Long Rides

Consider a racer with a maximum heart rate of 200 beats per minute, who performs the following events by himself, without the benefit of slipstreaming or drafting a group of riders.

25-mile time trial: It takes 60 minutes. The athlete can maintain 25 miles an hour, with a heart rate of 185 beats-per-minute or about 92% of his maximum.

100 miles: It takes 4.5 hours. The athlete can maintain 22 miles an hour. The heart rate is 160 bpm, or about 80% of maximum.

200 miles: It takes 10 hours. The athlete can maintain 20 miles an hour. The heart rate is 140 or about 70% of maximum.

2500 miles: It takes eight days. The athlete can maintain 13 miles an hour. The heart rate is 120 or about 60% of max.

As a beginning racer, your times will be slower, but your percentage of maximum heart rate will be similar.

Power vs. Heart Rate Pacing

In the final analysis, riders often need to rely on feel, intuition, and experience in calculating the best pacing strategy for a situation.

To help accelerate the learning curve, heart rate monitors or power meters can help.

For many reasons, power is a better metric than heart rate for pacing. The main drawback to using power is expense: power meters (which include heart rate monitors) are much more expensive than dedicated heart rate monitors.

Pacing Exceptions

Drafting

Cycling is different from running in the sense that drafting, or riding in another’s slipstream, is much more important. Since you can use more than 20% less energy riding behind another rider, or group of riders, a fast-paced group provides enormous benefit in overall time.

It is possible to draft within a group at a heart rate 30 or more beats per minute below what would be required to ride alone at the same speed. So it might be worth it to exert yourself a little bit more than your pacing strategy allows to reap the enormous benefits of group travel.

It might be worth working harder than planned over the top of that hill, to be able to stay with the group down the hill and along the flats.

Other Strategies and Tactics

Sprints or finishing kicks, hill-climbing ability, and other tactical considerations often affect race strategy in mass start events as much as pacing.

Prove the Value of Pacing for Yourself

It is easy to prove the importance of pacing, on your own, with a simple test:

Perform the test on a stationary trainer, in a hard gear, riding with one leg, using a cadence computer.

Let us assume that you find the perfect gear for which 55 rpm is the most rpm you can maintain at a steady cadence for 4 minutes. After several weeks, try this experiment: Ride a cadence of 53 for the first 2 minutes, and then try to ride 57 rpm for the last 2 minutes. At your next workout session, try riding at a cadence of 57 for the first 2 minutes, and 53 for the last 2 minutes.

Which way was harder? The vast majority of riders find the slow-start strategy much easier.

Short Events up to 15 Minutes: 51/49 Principle

In its most basic, simplistic form, pacing usually means even effort throughout the event.

Reports from many coaches and studies confirm that in events of up to 15 minutes, going at about 98% race pace the first half and 102% race pace the second half is the best strategy. That is, the first half takes about 51% of elapsed time, the second half 49%.

Longer Rides: Even Pacing

The longer the ride, the closer the overall half splits are to 50/50.

A 40K championship TT might have nearly even splits. If the 40K were to be divided into 4-kilometer tenths, however, the first tenth might be at 49% race pace, and the last tenth at 51%. This means that most of the race might be paced at 6 minutes per 4-kilometers. The first 4K might be paced 5 to 10 seconds slower, the last 4K that much faster.

Pacing for a 2–1/2-Hour Mountain Bike Race

Let’s consider pacing and a pro mountain bike race. The value of pacing here is doubly apparent because riders start together, yet drafting usually plays only a minor role. Watch good pacers and typically you will see them hang in 10th to 20th place the first lap and rise to the top 5 or 10 at the end of the race—passing many riders who do not pace well.

It is common to see the very best racers in a pro field riding together for the first half of an event. Although somewhat ahead of the rest, in the last half of the race the gaps grow much larger as the best test themselves and their competition by riding closer to their physiologic limits.

A possible perfect pacing might be to ride 96% of overall average pace in the first half hour, 98% of overall average pace in the second half hour, average pace in the third half hour, 102% of overall average pace in the fourth half hour, and 104% of overall average pace in the fifth half hour. This method has many theoretical and practical advantages. For example, it allows fuel and fluid consumption early in the race—where it can do the most good.

Pacing strategy A in Figure 2 depicts this strategy.

Starting out too fast, the most common error, might result in finishing times 1% to 3% slower than optimal. These strategies are depicted on rows B, C, and D.

Occasionally riders who are not warmed up, or for other reasons, start out too slowly. This also results in a loss of optimal finishing time, and is depicted in row E.

Note that even starting out at almost 10% below your optimal overall average pace may result only in a 1% loss in optimal finishing time.

Consider that you are in a mountain-bike race. Riders range in ability from 2% faster to 2% slower than you. In a 2½-hour mountain bike race without pacing, their finishing times are therefore from 3 minutes faster to 3 minutes slower than yours.

Naturally, if faster competitors adopt a perfect pacing strategy, they will do better than you. But if they have suboptimal pacing and yours is perfect, consider how you’ll fare.

Figure 3 shows a matrix of finishing times of 39 competitors. They are of 13 ability levels ranging from 2% faster to 2% slower than you. There is a competitor in each level who adopts one of the three pacing strategies B, C, or D above. We will ignore strategy A because riders who pace perfectly will finish according to their fitness. We will also ignore strategy E because it is rare for racers to start so slowly; you will never see these riders again after the start of the race unless they are a lot fitter than you are.

Of your 39 competitors, without pacing, on average, you’ll be in the middle, faster than 18, slower than 18, the same as 3. On average, you’ll finish about 20th.

With a perfect pacing strategy, you’ll finish faster than all riders except five. Three will beat you and you’ll tie with two. On average, you’ll finish 5th. That’s 15 places better!

When Will You Catch Riders?

If you pace, and your competitors don’t, even the worst rider in the group will jump ahead of you near the start line, to an early lead.

Of course, with pacing, you’ll catch all the riders whose ability level is below yours.

It’s surprising to many riders how long it takes to catch poorly pacing riders. In a 2½-hour event, for riders equal to you in ability, you’ll catch the worst pacing rider only near the end of the second hour.

Of the 18 riders faster than you, you’ll catch 15. You’ll catch these riders only in the last half hour of the race.

Other Mountain Bike Considerations

In a real race, racing abilities will be greater than plus or minus 2% of your fitness.

You may need to give some consideration to the effects of single track and work slightly harder than optimal to gain a good position when strategically important.

Road or Track Time Trial Pacing

The same principles discussed in the mountain bike example above apply to shorter and longer time trials.

Even in events as short as the kilo—1-kilometer on the track—an event just over 1 minute, a pacing strategy is helpful.

Although some riders insist that the correct way to ride the kilo is flat out from the gun, we know no riders really do this. There is a subconscious pacing, even if riders believe otherwise. How can I say this?

Because of the many track riders who have been tested at the Olympic training center, in an anaerobic test called the “Wingate.” In this test, a bicycle ergometer is slowed by a set of weights. An athlete’s power output is recorded by a computer during a 15- or 30-second test.

Athletes are instructed to work as hard as they can from the beginning of the test—they are told to immediately reach peak power—and to keep going as best they can for the 15 or 30 seconds.

When athletes know ahead of time that the test will last 30 seconds, they inevitably don’t listen to their instructions. The same athletes have lower peak powers for 30-second tests than they do for 15-second tests.

When athletes don’t know ahead of time how long they will pedal, they have a lower overall power output when they ride as if the test will last only 15 seconds—but it lasts 30.

These athletes frequently deny that they are pacing—but their power outputs belie their deeds. And they’ve done the right thing—because their overall power output for 30 seconds is greater with pacing.

At the other end of the racing spectrum, I coached a Race Across AMerica (RAAM) Team that wanted to reach the Arizona border first—because every team that previously won had reached that border first.

I advised the team: “Pace.” I convinced the members that reaching the border first worked either because the winning team was that much stronger, or because no other competitive teams were pacing either. (They paced. They reached the border first. They won. They set a RAAM record.)

When Will You Catch Riders?

Consider a roughly 4-minute 3-kilometer track pursuit event in which your competition is a rider of equal ability.

It may be that your competition has the reasonable strategy of riding each kilometer in 1:20 for a total time of 4 minutes.

Following the 51/49 principle described above, you may be able to finish the 3-kilometer event in 3:59. Taking into account the several seconds needed to start, perhaps your splits will be 1:23, 1:19, 1:17.

In this scenario, you will pass your competition with about 20 seconds to go.

Criterium and Road Race Pacing

Most of the time, it pays to be an odds player. That doesn’t mean gamble. To the contrary. It means understand the likelihood of success in a variety of racing circumstances, and consider your actions accordingly.

In roughly uniform fields, at the beginning of almost all mass start races, breakaways are unlikely to be successful because everyone is fresh, no one has yet been dropped because of mechanical or other problems, and sharply varying energy rates early are likely to result in lower power outputs later in the race.

By riding smoothly and conserving energy early in mass start events, studies and experience show you are likely to have the reserves for the inevitable crunch that occurs later.

Pacing for a 100 mile Century Bike Ride

You can quickly exhaust your glycogen stores by starting out quickly on a century. Why care?

Because you might not finish. Or you’ll finish with a slower time than you could otherwise achieve.

Riding speed does not increase proportionally to energy output. Since air resistance increases at more than the square of energy output, you’ll get a faster overall speed by pacing.

Consider this simple example: Riding a fast downhill. You might marginally increase your speed by pedaling furiously in a big gear—but the speed improvement is slight. You would probably do much better coasting and resting.

Working at 75% of your max? You’ll spread out your glycogen stores for many hours. Work at 90% and you might go a few miles an hour faster. But when you’re out of glycogen, the difference between speed at 60% and 75% of max is a lot more than a few miles per hour!

Pacing for Ultra Endurance Cycling Events

As in century pacing, spreading out your glycogen stores over many hours will result in a better overall time.

After 12 hours almost all glycogen is gone. You power output depends upon fat stores and the amount of fuel you can ingest—riders can typically use 250 calories of carbohydrates per hour to fuel themselves while riding.

If your pace is too high you will be too tired to eat or the blood flow to your gastrointestinal tract will be too restricted; you won’t even be able to consume that amount. In conditions of heat and humidity, you may not be able to keep up with sweat and other fluid losses. Your best choice is to choose a slower pace. With a slower pace two things happen: you can drink more and you sweat less.

When it’s hot and humid a slower pace also helps prevent hyperthermia—overheating.

Special Pacing

Pacing may also be required under other special circumstances. For example, if you ride through farmland with innumerable insects, you may need to slow your pace so that you can nose breathe and avoid inhaling bugs.

Pacing Isn’t Everything, Though

Pacing is a very important strategy. In time trials and mountain bike racing, it is crucial. Several of the pro mountain bikers I coach have had their best races after learning patience and pacing. Even in mass start events, it can be very valuable.

On the other hand, it’s not everything. At a recent road race in Arizona, I and three other teammates in four separate races broke away solo from our respective fields with 10 to 90 miles left. Our fields could have caught us had they been organized.

Mass start racing is much more than pacing: It’s feints, it’s who has the best sprint, it’s who wants not to work thinking someone else will, it’s who wants to help someone, and it’s who can’t stand a rival being off the front.

Sometimes, “No guts, no glory.” Three out of the four of us stayed away and won our races.

What You Need to Pace Effectively

• Self knowledge. You need to know your limits. Based on past performance, you need to know how hard you can go.
• Self control. You must not let others dictate your pace.
• Correct equipment. For example, you need the right gears. If you have a straight block 12-21 cogset and want to climb a 10% grade at 70 rpm and at less than 75% of maximum heart rate, you may need easier gears. You may need a heart-rate monitor.
• Warm-up. The shorter and more intense the event, the more important it is to warm up. In many events, to achieve target pace your overall effort level will be too low if you do not warm-up properly.
• Nutrition. Food and fluids will help you maintain target pace.

The Bottom Line About Pacing and Cycling

Learning to pace oneself is a hard lesson for many riders to learn. It is so very tempting to take off from the start at too fast a pace—there’s all the excitement and enthusiasm, and you certainly don’t want to look like the slowest person there!

However, if you start at a reasonable pace, at the half-way point or later you’ll be passing a lot of people who thought they left you in the dust at the beginning.