Easy runs get no love. Whenever a video is made of elite runners in training, it’s always some type of workout that’s filmed (a track session, hill repetitions, a long run at marathon pace), never an easy run. This is the case despite the fact that easy runs are the foundation of any good training program and collectively contribute more to race-day performance than any other type of run.

The tendency in our sport to take easy runs for granted has practical consequences. These runs are considered so basic that no one can possibly screw them up, and yet no run type is screwed up more often or with greater consequences. I’m referring to the moderate-intensity rut, of course—the almost universal tendency of runners to do their easy runs too fast, slightly above the ventilatory threshold (VT), making each session more stressful than it should be and creating a chronic burden of fatigue that inhibits fitness development and compromises performance in runs that are intended to be harder.

But I’m sick of talking about the moderate-intensity rut. Today I’d like to talk instead about another important element of easy run execution, which is allowing your easy run pace to vary wildly from day to day and even within individual easy runs based on how you’re feeling. Contradictory though it may seem, only by pacing yourself inconsistently in your easy runs will they consistently serve their intended purpose, which is to ensure that your overall training workload is close to, but within, the limit of your body’s present tolerance for training stress.

Erratically paced easy runs are essentially a method of ensuring that a good training plan is correctly applied. Before you start to train for any important race you should, of course, devise (or choose) a training plan. Your overarching goal in developing this plan is, as I just suggested, to prescribe a workload that is near to, but less than, the limit of your body’s tolerance for training stress. To achieve this goal, you need to decide on an appropriate volume of training, design key workouts that are hard but not too hard, and determine the right target paces for these key workouts.

If you are experienced and knowledgeable enough, it’s not too difficult to come up with a training plan that fits. But no matter how experienced and knowledgeable you are, you cannot design a plan that prescribes the perfect workload every day for its entire length. This would require an almost godlike degree of foresight. The power of planning is limited by the impossibility of knowing exactly how your body will respond to the training you plan. Therefore your plan must have built-in flexibility, allowing for a certain amount of responsiveness in its execution.

It’s best not to change things unnecessarily, though. You had specific reasons for deciding how much running you would do and what your key workouts would be and how fast you would run in those sessions. These elements of your training are not the first ones that you should alter in response a discrepancy between expectation and reality, such as not feeling good in several consecutive runs. A much better way to tweak your training on the fly is to adjust your easy run paces to ensure that your workload is at every point high enough but not excessive. This approach makes a lot of sense because whereas no single easy run is terribly important, collectively easy runs account for the bulk of your total training stress, so they present a lot of opportunity to fine-tune your workload.

The way to do this is to try to maintain a consistent comfort level throughout all of your easy runs regardless of pace. Ideally, you will feel very comfortable from the beginning to the end of every easy run you do. On days when you are carrying fatigue from recent hard training or you’re just feeling flat for no particular reason, staying comfortable may require you to run one or even two minutes per mile slower than your ventilatory threshold pace. And on days when you’re feeling good, your legs may want to carry you right at VT pace, and there’s no reason not to do so in this situation. And if you’re like me and you often feel bad and good at different points within a single easy run, you should allow your pace to fluctuate.

How you feel during your easy runs is not arbitrary. It’s information about how your body is doing and what sort of training stimulus is appropriate. By allowing comfort to set your pace, you will not miss out on opportunities to run faster and get a bigger training stimulus when your body’s up to it but at the same time you will avoid overtaxing your body when it requires a gentler training stimulus. And the long-term effect will be that your overall training workload is in the Goldilocks Zone—high enough but not too high.

The pros practice erratic easy run pacing. For example, during an easy run I did with the Northern Arizona Elite team a few weeks before the Chicago Marathon, Aaron Braun observed that as his key workouts were getting faster and faster, his easy runs were getting slower and slower. (I think we were jogging at just under 8:00/mile at the time, or more than 2.5 minutes per mile slower than Aaron’s VT pace.) Of course, Aaron wasn’t slowing down in his easy runs because he was physically incapable of going faster. He was slowing down because he chose to, and he chose to because like most pros he habitually paces his easy runs by feel, aiming to maintain a consistent comfort level throughout all of them.

Now you try it!