If You Feel Like You’re Not Making Progress in Training, Use This Coach’s Method to Better Track Your Runs—and Improve Performance

We’ve all been there: You head out for an easy run and settle into your usual pace, but after a mile or two, your breathing feels labored and you notice your heart rate climbing higher than normal. However, you’re still going at your usual pace on your usual route, so what gives?If you judge the run by pace alone, you might see no reason to change anything. But those other signals suggest you’re paying a higher price than usual to hold that speed.Of course, you probably already know that factors like heat, hills, fatigue, and stress can make your usual pace feel harder. But with so much advice about what to pay attention to during a run, it can be tough to know which signals to trust and how to use them to evaluate your effort.And without a clear way to interpret those signals, you might inadvertently push too hard on an easy day or miss the intended effort during a speed workout. Repeat these mistakes, and over time, you can disrupt the balance between training and recovery, making it harder to build the fitness you need to race your best.The solution: A system from ultramarathon runner and endurance coach Nick Farr, head coach and founder of P3 Fitness. Farr organizes running feedback into three categories—performance output, biological load, and subjective feedback—and uses them together to understand how a run is unfolding.Here’s how to use Farr’s three-category system to make every run count, build fitness more consistently, and arrive on race day ready to perform your best.Why Your Run Data Needs Context“No single metric tells you the whole story [of a run],” Farr says. For example, your pace tells you how fast you ran. But, inherently, it can’t tell you how difficult that pace felt or how your body responded to that pace.To get a fuller picture, Farr separates training feedback into three categories, each of which answers one of those three questions:Performance output: What work are you doing?Biological load: How is your body responding to that work?Subjective feedback: How does the effort feel?Evaluating the answers to these questions in concert with one another helps Farr and his athletes understand whether a run matches its intended purpose. It also gives runners a way to recognize when environmental conditions, fatigue, or other factors might call for an adjustment.Performance Output: Shows What You’re DoingPerformance output describes the work you produce during a run. Metrics like pace, speed, distance, time, elevation, cadence, stride length, and power fall into this category, Farr says.These metrics help you track what you accomplish. They show how quickly you covered a route, how far you ran, or how much climbing you tackled. You can also compare output across runs to see how your performance changes over time.But output alone offers an incomplete view of the effort. You might finish an easy run at your usual pace, even though heat, hills, or fatigue made it much harder than normal. If you focus only on the pace number, you could miss the signs that you pushed beyond the effort you intended.Biological Load: Reveals How Your Body Responds to EffortBiological load, which Farr also calls internal or physiological load, describes how your body responds to the work you’re doing. Numbers such as heart rate, breathing rate, oxygen consumption, and core temperature can all offer information about your body’s response to a certain pace, environment, or training block.These markers help put your output in context, Farr says. Consider a 90-degree July day: You might still manage your usual pace, but your heart rate and breathing will rise as your body works harder to maintain it. Those signals give you more information about the cost of the run than pace alone.The key is, you don’t need to track every single biological load marker out there, Farr says. Start by paying attention to a signal available to you, such as heart rate, and notice how it relates to the effort you’re trying to maintain. Over time, comparing your heart rate on similar runs can help you recognize when your body is working harder—or less hard—than usual at a familiar pace.Subjective Feedback: Captures How the Effort FeelsSubjective feedback is your own perception of the run. You can describe it with a number corresponding to rate of perceived exertion, or RPE, on a scale of 1 to 10. Other common examples of subjective feedback evaluations include your ability to carry on a conversation during an easy run or if your legs begin to feel heavy at the end of a speed workout—basically any evaluation that you come up with yourself.The ability to subjectively evaluate your own running is crucial because your experience of a run adds perspective to the data on your watch. A pace that usually feels comfortable may feel demanding on a day when you’re carrying fatigue or dealing with stress. Paying attention to that change can prompt you to take a closer look at the rest of your feedback and make adjustments, if necessary.Farr even encourages his newer athletes to run only by perceived effort so they can learn to recognize how different intensities feel. After a few weeks of developing awareness of what their efforts feel like, he layers in metrics from the two other categories, such as pace and heart rate, to help them get a fuller picture of how they should execute each workout on their training plan.The Real Value: Combining the Three CategoriesEach category tells you something useful on its own, but Farr finds true value in using at least one metric from each category during each run or workout.His starting guideline: If two of the three categories agree, use those two to help guide your decision-making in the moment.Let’s once again return to the easy run from the beginning. Your pace may match what you planned, but if your heart rate has climbed and your effort feels much harder than usual, biological load and subjective feedback both suggest the run is costing you more than expected. In that situation, slowing down can help you bring the effort closer to the goal of the easy run: to maintain an easy pace that builds mileage, helps you recover, and builds your aerobic system.But the reverse can also happen. On a cool day, your planned pace may feel easier than expected while your heart rate stays lower than usual. Depending on the purpose of the run, those signals might give you confidence to push a little harder to get the intended benefit, Farr says.The goal is to interpret the feedback in light of what you set out to accomplish. A slower pace doesn’t automatically make a workout less valuable if your biological load markers match your intended effort level.“On any given day, the pace may look slightly different, and that’s totally fine,” Farr says. “That’s just a shift of the output, not a shift of the value of the workout.”How to Use This System in Your RunningYou don’t need to lock in and stare at your watch or overanalyze every single sensation throughout a run. Farr’s approach begins with understanding the goal of your workout, checking how the signals relate, and using what you learn to guide future training.1. Before the run, identify the purpose of the workout. Know what you want to accomplish and what kind of effort the session calls for so you hit your target. If the goal is an easy run, for example, think about how that effort should feel and what feedback could help you stay controlled.2. During the run, check the relationship among the categories. Notice your output, pay attention to how your body feels, and check a biological marker available to you. If the signals disagree, consider whether environmental conditions or fatigue might explain the difference—and whether an adjustment would better serve the run’s goal.Farr keeps pace and time on one watch page and heart rate on another. This setup lets him check the information when he wants it, while also paying attention to how the effort feels.3. After the run, record what happened. Review your output and biological data, noting how the run felt and what conditions you faced. This gives you a reference for future workouts. For example, if you repeat a speed session from a cool spring day in the summer heat, your log can help you recognize that you may need to slow your pace to match the intended effort level.4. Over time, look for patterns. Farr suggests periodically running a familiar route at a consistent pace and comparing your heart rate and recorded effort—if you’re someone who always picks a new route, try returning to the same one once a month. Similar conditions make the comparisons more useful. If the same pace gradually feels easier or comes with a lower heart rate, that pattern may offer a sign of improving fitness.5. Get better at evaluating your signals. During workouts, Farr encourages runners to estimate their pace before checking their watch, then compare the number with the guess. For example, if your threshold pace is around 8:00, start a controlled interval by feel (going for that 7 or 8 out of 10 RPE), guess your pace, and then check your watch. Over time, you can learn to settle into your target pace sooner, rather than spending the first part of each rep speeding up and slowing down to find the right level.With practice, you can get better at connecting your output, how your body responds, and how the work feels. Those connections can help you keep easy runs easy, make sure hard workouts reach the intended stimulus, and prioritize recovery so you’re ready to go in time for your next session.String these well-executed runs together, and you can build fitness more consistently, arrive at the starting line better prepared, and put yourself in position to race faster.Matt Rudisill is an Associate Service Editor who has been with Runner's World since 2025. A Nittany Lion through-and-through, Matt graduated from Penn State in 2022 with a degree in journalism and worked in communications for the university's athletic department for three years as the main contact and photographer for its nationally-ranked cross country and track & field teams. Matt was also heavily involved in communications efforts for Penn State football, men's basketball, and women's gymnastics. In his role with Runner's World, Matt has interviewed Olympians, world champions, and countless experts in the field to create service content that helps runners of all ages and experience levels train smarter and race faster. When he’s not out jogging, Matt can be found tweeting bad takes about the Phillies or watching movies.