Making Sense of Metrics

Running Metrics - Explained

If you’ve spent any time running or training with a watch, you’ve probably been exposed to a lot of numbers, such as heart rate, VO₂ max estimates, training zones and recovery scores to name a few.

For some people, this data is motivating. For others, it’s overwhelming.

The reality is: these metrics can be incredibly useful, but only if you understand what they actually mean and how to apply them.

Heart Rate

Heart rate is one of the most accessible and useful metrics for endurance training. It gives you insight into how hard your body is working, not just how fast you’re moving.

But it’s also highly variable.

Your heart rate can be influenced by:

• Sleep

• Stress

• Hydration

• Caffeine

• Hormones

• Heat and altitude

So while it’s helpful, it’s not something to follow blindly.

Instead, think of heart rate as a guide:

• Easy runs → lower heart rate, conversational effort

• Workouts → higher heart rate, more strain

• Recovery days → intentionally keeping it low

If your pace is slower than usual but your heart rate is high, that tells you something important: your body might need more recovery.

Setting Heart Rate Zones

I'd highly recommend working with a coach to determine your heart rate zones. Outdated formulas can be used, but finding accurate heart rate zones are actually more variable than many realize.

A lot of watches automatically generate heart rate zones, but they’re often based on generalized formulas.

The most common is:

• 220 – age = estimated max heart rate

The problem? It’s not very accurate for individuals.

A better approach is to base zones on your actual training data.

Here’s a simple, practical framework:

• Zone 1–2 (Easy / Aerobic): conversational, sustainable for long periods

• Zone 3 (Moderate): steady effort, slightly uncomfortable

• Zone 4–5 (Hard): threshold and above, difficult to sustain

If you want more precision, you can:

• Use a field test (like a threshold workout)

• Work with a coach to dial in zones based on your training

• Or use lab testing (like a VO₂ or lactate test)

But for most people, perceived effort + heart rate trends over time is enough.

VO₂ Max

VO₂ max is often seen as the “gold standard” of fitness.

It refers to the maximum amount of oxygen your body can use during exercise. In simple terms, it reflects your aerobic capacity.

Most watches estimate VO₂ max based on your pace and heart rate. These estimates can be helpful for tracking trends but they can also vary greatly compared to clinical results.

A few important things to understand:

• It’s partly genetic

• It’s trainable to a point

• It’s not the only predictor of performance

You can improve your race times without a huge change in VO₂ max by improving:

• Running economy

• Lactate threshold

• Fueling and recovery

So if your watch says your VO₂ max hasn’t changed, but you’re running stronger, that's still improvement.

Training Zones: Bringing It All Together

Training zones help structure your workouts so you’re not doing everything at the same intensity.

A common mistake is spending too much time in the “middle” which is not easy enough to recover, but not hard enough to improve.

A more effective approach is polarized (or at least varied) training:

• Most runs: easy, aerobic

• Some runs: intentionally hard

• Very little: moderate “gray zone” work

This is where metrics can be helpful:

• Heart rate keeps easy runs actually easy

• Pace and effort guide workouts

• Trends over time show whether your fitness is improving

The Bigger Picture

Metrics are tools. However, they’re not your goal.

It’s easy to get caught up in:

• Hitting the “right” zone

• Watching every fluctuation

• Questioning every number

But your body isn’t a lab experiment, and normal fluctuations are part of life.

The most important skills you can build are:

• Awareness of effort

• Consistency in training

• Ability to adjust based on how you feel

The data should support those, and definitely not replace them.

How I Use Metrics in Coaching

When I work with athletes, we use metrics to create context, not pressure.

That might look like:

• Adjusting zones based on real training data

• Looking at trends instead of single workouts

• Combining heart rate, pace, and perceived effort

• Using data to catch under-recovery early

The goal is to get a better sense of your full picture, not over analyze evert detail.

If you’ve ever felt overwhelmed by all the numbers, you’re not alone. And you don’t need to use everything to train effectively.

Ready to get started? Schedule a free consultation today.

Start simple. Stay consistent. Let the data support you—not stress you out.