Here are three tiers of training benchmarks that will help you understand if you are getting fitter.

According to the 2024 State of Trail Running Report, 71 percent of trail runners do not use any formal training, coaching, or nutrition services. That’s the majority of people toeing the start line at your next race, building their own plans, managing their own training, and trying to figure out on their own whether any of it is working.

That last part is where most self-coached runners get stuck. You’re logging miles, showing up consistently, putting in the work. But when you want to know whether you’re objectively getting fitter, the honest answer is usually “I think so.” That may not be good enough when you’re preparing for something that’s going to demand every ounce of your capabilities.

For the athletes I coach, this question has a clear answer. We track specific benchmarks across every training block, and progress isn’t a subjective feeling, but something we can see in the training data. That’s one of the real advantages of working with a coach. But it doesn’t mean self-coached athletes are without options.

There are concrete, accessible ways to measure your own fitness progress, regardless of your experience level or what tools you have access to. This article walks through three tiers of benchmarks, organized by training structure and available resources. Start where you are. If you get to the end and decide you’d rather hand this off to someone who does it full time, that’s what coaching is for.

One thing worth establishing before we get into the methods. Fitness progression in endurance training is slow. Meaningful adaptation happens over weeks and months, not days, and a single data point tells you almost nothing, but a pattern tells you more of the story.

This matters because most runners abandon a benchmark before it has time to show them anything useful. They check their average pace and heart rate on a Tuesday, compare it to last Thursday, and conclude nothing is changing. That’s not how adaptation works. Whatever method you use from this list, consistency of measurement is the only thing that makes it meaningful. Track the same thing, under similar conditions, long enough to see a trend. That’s how you can determine if you’re getting fitter.

Tier 1: All You Need Is a GPS Device, Heart Rate Monitor, and a Running App

These require no structured training plan or coach. If you’re running consistently and tracking basic data, you already have everything you need and works remarkably well if you’re a newer athlete.

The first is easy run heart rate trends. As cardiovascular fitness improves, your heart gets stronger and pumps more blood per beat, known as stroke volume. It doesn’t need to work as hard to deliver the same oxygen to your muscles.

In practical terms, that means a lower heart rate at the same pace and effort over time. Pick a regular route, run it at a consistent easy effort, and log your average heart rate. Don’t expect it to move week to week, but three to six months into training, a consistently lower heart rate at the same pace is a real and meaningful fitness signal.

One important caveat: environmental conditions matter. Heat and humidity drive heart rate up independent of fitness, so comparing a summer run to one from February tells you nothing useful. Keep your comparisons within similar conditions, same season, similar temperature range, for the data to actually mean something.

The second is Strava segments. A segment is a repeatable course—same distance, same terrain, same start and finish every time. Run it faster under comparable conditions later in your training cycle and you’re likely getting fitter. Most runners already have months of segment data sitting in their accounts and have never used it this way.

There’s one trap worth naming though. Benchmarking and chasing are two different things. Use segments intentionally, on days designed for a harder effort, not as an excuse to blow up a recovery run chasing leaderboards and kudos. Measuring fitness at the cost of building it is a bad trade.

Tier 2: If You’re Following a Structured Training Plan

If your training includes designated quality sessions, you have access to a more precise benchmark: interval performance tracked across training blocks.

The concept is straightforward. Run the same workout at a similar point in two different training blocks and compare the output. Here’s a practical example. The workout is four repeats of ten minutes at lactate threshold effort, which is an eight to nine effort on a scale ten. In your first workout of the training block you average an eight minute per mile pace for each interval. After a few weeks with these similar workouts sprinkled in and then a recovery week, you run the same workout again while fresh and average 7:50 pace across all four intervals. Same structure, better output. Your fitness has likely improved.

For trail runners, raw pace alone is an unreliable comparison tool because terrain and elevation vary too much. Use NGP, normalized graded pace, which you’ll also see labeled as GAP (grade adjusted pace) on Strava. There are minor differences, but the concept is the same. It accounts for climbing and descending and gives you a fairer apples to apples comparison across different days and conditions.

A few variables matter here. Control for fatigue state as best you can. Comparing a workout done fresh at the start of a training block to one done deep in a fatigued build isn’t a fitness comparison, it’s a fatigue comparison. In training, we often take two steps backwards in performance while fatigue accumulates, then after adequate recovery and adaptation, we take four steps forward. Same workout, similar conditions and surface, similar point in the training cycle. That’s when the data actually tells you something.

Tier 3: Testing

This is the most precise benchmark on the list to determine if and how you are getting fitter, and it is the most involved. It’s also optional for most people reading this. If Tiers 1 and 2 are giving you useful information, you don’t need to go further.

For those who want the clearest possible picture, LT2 (lactate turn point) testing is worth understanding. As exercise intensity increases, your body produces lactate as a byproduct of energy metabolism. At lower intensities, your body clears it as fast as it produces it. LT2, your second lactate threshold, is the point where lactate begins to accumulate faster than your body can clear it. Above that point, the clock is ticking and you can’t sustain that effort indefinitely.

It’s one of the primary determinants of endurance performance, and for ultrarunners specifically, training to push that threshold higher means you can sustain a faster pace before things start to fall apart. Tracking how it shifts over time gives you a direct window into meaningful fitness change.

The field test protocol is simple. Run a maximal effort for 30 minutes on a flat, controlled surface. Your average heart rate over the final 20 minutes gives you a reliable estimate of your lactate threshold heart rate. Your average pace over the full effort approximates your threshold pace. Run the same test at a similar point in different training cycles and compare. If threshold pace improves, fitness has improved.

For serious athletes who want a more precise way of understanding if you’re getting fitter, a full lab assessment adds another layer. A trained technician can measure both VO2max and lactate threshold directly, which allows them to express your threshold as a percentage of VO2max. That ratio is meaningful. Two athletes can have the same VO2max and very different threshold percentages, and the one who can sustain a higher fraction of their maximum for longer is almost always the better endurance performer.

Improving that percentage over time, through consistent training, is one of the clearest indicators of real physiological development. For athletes working with a coach, this is exactly the kind of data that drives long-term programming decisions.

The Only Comparison That Matters

Progress in endurance training isn’t just a feeling, although that is a signal too. It’s a pattern of outputs measured consistently over time. Start with Tier 1. Easy run heart rate trends and Strava segments give you more actionable information than most self-coached runners ever use. If you’re following a structured plan, add Tier 2 and start tracking interval performance across training blocks. If you want the most precise picture available, Tier 3 gets you there.

Whatever tier fits your situation, the principle is the same. Track consistently, give it time to show a trend, and compare yourself to yourself. Not your training partners, not someone else’s numbers, not where you think you should be.

If you want to go deeper on any of these benchmarks, I put together a full video walkthrough on the CTS YouTube channel.