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Pacing isn’t just a skill—it’s a strategy that can make or break your race. Get it wrong, and you risk crashing before the finish line. Get it right, and you’ll power through the final stretch feeling strong, confident, and in control.
The golden rule? Start conservatively, finish strong. And the longer the race, the more critical that becomes.
In this guide, we’ll dive into the science behind risk-based pacing, explore how your body and mind respond to different strategies, and show you how to build a pacing plan that works best for you.
Why Smart Pacing Is All About Balance
Pacing is often a difficult concept to grasp for new runners.
The best way to appreciate pacing is to consider the cost/benefit ratio. Too high an energy expenditure (cost) and the benefit (result) will decrease overall. Too low of an energy expenditure, and the result will decrease as well.
In order to perform optimally, the energy expenditure needs to be not too high and not too low.
In other words, being an efficient runner is a function of balance.
Race pace is determined during training and based on assessments of your fitness level. Correlating your effort level, such as lactate threshold, to assessment methods (i.e., heart rate, power, stroke count, RPE, etc.) will enable you to track your pace throughout an event.
For example, while you might want to break three hours in a marathon, if you cannot run anywhere near the pace required to do so, this is not a feasible goal.
Assuming you have a time goal, the goal must be realistic.
Smooth and steady is always the better pacing option than erratic and punchy. The more erratic you pace yourself, the less efficient you’ll be.
For example, while it might seem faster to sprint up the hills and recover on the downhills of a course, this will likely result in a slower time than a competitor that kept their effort constant.
This does not mean that you should not push harder in some sections of a course, but the efforts need to be calculated to ensure the overall pace is sustainable for the duration of the event.
While specific to cycling, a study that examined power output during Olympic distance triathlons found that large power variations equated to a higher overall workload versus cycling at a constant power output.
Additionally, a study1Billat, V. L., Palacin, F., Correa, M., & Pycke, J.-R. (2020). Pacing Strategy Affects the Sub-Elite Marathoner’s Cardiac Drift and Performance. Frontiers in Psychology, 10. https://doi.org/10.3389/fpsyg.2019.03026 by Rapoport found that running at a constant pace is the most efficient pacing strategy. However, Rapoport noted that in order for running at a constant pace to be the most efficient strategy, the terrain must not vary.
Most outside courses have some sort of terrain variation. In these cases, the most efficient way to run is not at a set pace but rather at a set level of exertion or effort.
The image below shows various pacing strategies. Of the four strategies, only the orange and black are recommended.
The Fatigue Factor
Intensity and fatigue are invariably linked to endurance sports training and, thus, pacing. The longer and/or more intensely an individual continues to exercise past the initial sensation of muscle tightness, the more fatigued the person will become.
If exercising to an extreme level, eventually, the level of performance will decrease, and if continued long enough, exercise cessation will likely occur.
The human body regulates itself to ensure survival and to operate efficiently. What is up for debate is the exact means by which the body regulates itself and to what extent.
Fatigue is a catchall term that is used in many different contexts. For example, fatigue can be used to denote mental or physical stress.
Additionally, the exact definition of fatigue is also up for debate. Some view fatigue as a progressive process that begins at the onset of exercise, while others view it as the involuntary endpoint of an exercise bout.
Causes of physical fatigue likely differ based on the mode of exercise and its duration and intensity.
Physiological changes that occur within a muscle in regard to muscular fatigue are termed peripheral fatigue (PF). This is considered the traditional model of fatigue.
For example, if, when running, the quadriceps begin to “burn” and fatigue, this is indicative of a buildup of acidity within the muscle, which slows the runner and possibly causes the runner to stop.
In other words, the physiological changes that result in fatigue are isolated to specific, local muscle motor units.
Below is an example of peripheral fatigue:
CAUSE: Running uphill
RESPONSE: Buildup of intramuscular acidity – causing muscle burn
EFFECT: The runner slows or stops to recover
The opposing model of fatigue is termed central fatigue (CF). Central fatigue is the result of events within the brain and spinal cord.
The central governor theory focuses on the role of the central nervous system in monitoring physiological signals during exercise, with the premise that the brain is in a state of constant monitoring and will prevent overexertion to the point of physical detriment or death.
This theory claims that the brain is the ultimate regulator, i.e., the central governor, of all physical and physiological systems and regulates physical exertion and exercise through monitoring and subsequent regulation controls for the ultimate purposes of preventing serious bodily damage and/or death.
Timothy Noakes is largely credited with the central governor theory in 2005.
Exploring the Psychobiological Model of Pacing and Performance
The Psychobiological Model of Endurance Performance is the newest development in the theoretical understanding of limiters to performance and gives increased attention to the role of psychological factors, including motivation and willingness.
This model considers the decisions to slow, stop, continue, or accelerate in endurance-based tasks.
This model consists of two main aspects of motivation: potential motivation and motivational intensity.
Potential motivation is the maximum amount of effort a person is willing to expend in order to reach a goal, whereas motivational intensity is the amount of effort that a person will actually exert.
Of critical importance, this theory suggests that people will continue to engage in a task with the same level of intensity as long as they view their goal as remaining possible.
Therefore, motivation alongside the perception of effort becomes the ultimate determinant guiding an athlete’s decision-making in endurance sports in this theory.
Stick to the Script
It’s easy to get swept up in the adrenaline of race day and start chasing someone else’s pace—but doing so can derail your entire strategy. Sticking to your planned pace is crucial, especially early on when energy is high and crowds are buzzing.
That’s where prep races come in. They give you a taste of race-day energy and teach you how to manage it—without abandoning your pacing strategy.
Practicing with pacing tools in training, whether it’s heart rate, perceived effort, or pace, helps build the awareness you’ll need to stay on track when it counts.
That said, pacing isn’t rigid. Your race plan should reflect your training—but only if you’re healthy, rested, and feeling ready. If you wake up feeling off or your body isn’t responding, adjusting the intensity is not only smart—it’s necessary.
Listening to your body is one of the most underrated pacing skills you can develop.
Train Smart In A Group Setting
Many athletes enjoy training with others for the motivation, camaraderie, and accountability it brings. Group runs can make the miles go by faster and push you through tough days.
But while there are definite benefits to running with others, a common mistake is jumping into workouts that don’t align with your own training plan.
If the group is doing intervals and your plan calls for an easy run, pushing to keep up can throw off your progress or increase your injury risk.
It’s important to know the workout ahead of time and have the discipline to skip or modify it if it doesn’t match your goals. Social running is great—just make sure it supports your training, not sabotages it.
Why Racing Smart Comes Down To Risk Management
Proper pacing comes down to risk management.
As noted previously, go too easy, and you will likely miss the time goal. Go too fast, and you will likely blow up and miss the time goal.
However, with proper pacing, you can set yourself up with the best chance to succeed by managing risk appropriately.
It is common sense that the pace for a long-distance event (ex: ultramarathon) is slower than that of a short-distance event (ex: 5K).
While there are physiological reasons for this, the mentality of an athlete also plays a large part. Specifically, distance will dictate how fast an individual will pace themselves.
As an example – Jessica can run a 5K at an eight-minute-mile pace and has never run a marathon. On a whim, Jessica decides to enter a marathon without any specific training (obviously not a smart idea!).
Jessica paces herself at a 10-minute-mile pace during the marathon. But why? She has no previous experience telling her how fast to run, so why did she slow down so much in relation to her 5K pace?
The answer: While Jessica knows she can run at least 5K at an eight-minute pace, she believes that given the distance of a marathon, she would not be able to hold that pace throughout without blowing up. This is an example of risk management.
Let’s assume that Jessica miraculously (in lieu of her lack of training) makes it to 24 miles at a 10-minute pace without blowing up. She decides since there are only 2.2 miles left to go, she will pick up the pace. Jessica lifts her pace to 8:30 min/mile for the remaining distance.
Why didn’t Jessica pick up the pace prior to this?
For the same reason that she initially determined to run a 10-minute pace at the start ‒ there was too much risk of blowing up. With 2.2 miles left to run, she determined that the potential reward of a faster time was worth the risk.
In other words, she estimated that the reward (i.e., picking up the pace and finishing with a faster time) outweighed the risk (i.e., blowing up and not finishing or finishing with a slower time).
In layman’s terms, this represents that the intensity that one runs is highly correlated to the distance left to run. The farther from the finish, the higher the risk – and the closer to the finish, the lower the risk.
Mastering Pacing: Tools, Tactics, and How to Run by Feel
While there are countless pace assessment tools, below are the most popular.
- Heart rate monitor
- GPS devices
- Time
- Rate of perceived exertion scale (RPE)
- The talk test
- Time trials
- Pace calculators
- Power meter
- Training logs and apps
With regard to heart rate, cardiac drift is a phenomenon that elevates one’s heart rate without an increase in other performance metrics.
It is natural for cardiac drift to occur while exercising, especially in the latter parts of a training session or race. Cardiac drift can artificially increase one’s heart rate by as much as 10‒15 bpm.
Therefore, it is important to pace not only by heart rate but also by RPE.
Many experienced athletes are able to accurately determine their pace by feel. This comes from lots of experience and correlating their pace to pacing tools and RPE.
So how does one become accustomed to pacing by feel when running? Below are ways to test one’s ‘feel’ for pace.
Using a stopwatch, run a set distance at a desired pace (ex: run 3 miles in 24 minutes – 8 min/mile pace), but only look at the time once the distance has been run.
If you have a real-time GPS watch, you can guess your pace and then look at the watch to see how close you are.
While this is just one example of how to test one’s ability to ‘feel’ the pace, the tests must be done with some frequency in order to increase one’s proficiency at correctly pacing themselves by feel.
If you use a pacing tool(s) to determine your effort level, it is important to correlate the pacing tool pace with how you feel.
For example, your pacing strategy is to maintain an 8:30 min/mile pace during a marathon; if you cannot maintain this pace due to exhaustion or injury, you MUST slow down.
Failure to do so will likely result in a slower overall time at best and a ‘Did Not Finish (DNF)’ at worst.
Learning how to pace by feel is very important for any endurance athlete.
Pacing takes time, discipline, and commitment in order to implement and be successful at it. So be patient and focus on the areas noted in this post to become more proficient at pacing.
Your training and racing will thank you!
For a guide on assessing and training your marathon pace, check out this next guide:
