3 Effective Ways of Knowing How to Monitor Interval Intensity Without a Device

Three ways to monitor interval intensity without a device include the Talk Test, Fast or Fastest Speeds, or RPE (Rate of Perceived Exertion).

Three Ways to Monitor Interval Intensity Without a Device

  1. Talk Test – how many words are you able to say out loud while doing the work.
  2. RPE – how hard do the efforts feel.
  3. Fast or Fastest – pick a speed that you can maintain through the targeted interval length.

If you are an everyday endurance athlete hoping to improve your performance for your target event, you need to do some speed work – or intervals. 

Intervals, or kicking up your intensity for short periods, build speed, endurance, efficiency of movement, as well as bring a host of additional physiological benefits. 

But how hard should you run, ride, or swim? 

While heart rate monitors and power meters (on bikes) are great tools to know how hard to go, what’s the best way to determine intensity if you aren’t using those?

Or, what can you do if you want some additional feedback or assurance that the devices are working right? 

Three ways to monitor interval intensity without a device include the Talk Test, Fast or Fastest Speeds, or RPE (Rate of Perceived Exertion). 

Let’s take a step back, first, and talk generally about intervals.

Get Your Free Guide to Simplified Strength Training for Cyclists and Runners

Get the FREE "6+1=The Way to Better Health, Fitness, and Your Best Season Ever" ebook with your email. The guide will help you structure your strength training to prevent injuries and improve performance. No purchase or commitment required.

Targeting training by targeting energy systems

To understand how best to target our training, it helps if we understand how our bodies utilize energy. 

Think of the energy systems as a rocket bound for Mars. 

The first section (ATP-CP) gets the rocket off the ground quickly and forcefully but lasts only a few seconds. 

The second stage (mostly anaerobic) provides a slightly longer boost to get into space, and the third (mostly aerobic) keeps the space capsule going to where it’s going. 

So we need to target three distinct energy systems in our training. 

The only problem with this rocket analogy is that you use some of all systems while doing your endurance sport. 

All three work as a continuum, providing different amounts and sources of energy depending on the activity. 

Three energy systems work together to fuel your endurance adventure

The main idea of training is to stress the three systems so that they work better and you improve your performance. 

The “moderate” zone is mostly aerobic. This zone is the easier to monitor interval intensity.

This is where most of your training takes place. 

Your heart rate and effort are moderate and you do long, slow efforts. 

The “heavy” zone is mostly anaerobic, which means it requires carbohydrates to fuel the work. 

Heavy-zone intervals are tough. You have to hold a pretty high intensity for many minutes.

They boost the capacity of your heart to work and more efficiently utilize oxygen, fat, and glucose as fuel sources, among other benefits. 

The final zone is “severe,” which is essentially maximum efforts. 

These intervals last usually 60 seconds to five minutes. 

The “heavy” and “severe” zones require you to monitor interval intensity.

Devices can help monitor interval intensity

Power meters, heart rate monitors, and other devices are great at helping you monitor interval intensity. 

For example, you can program devices so you can follow a specific workout or beep when you’re in the right heart rate zone.

But your heart rate lags when you’re doing short intervals.

You don’t often get into the right training zone until up to a minute into the intervals, and these hard intervals are often only 30 to 90 seconds long! 

Plus, our bodies change daily and our training “zones” might not be perfectly set up.

So while devices are a good tool, learning to understand how your body responds to certain workloads is invaluable as you monitor interval intensity. 

The three subjective methods I propose can help you develop a deeper awareness of how to pace yourself.

Pace is another metric

Cyclists, runners and swimmers could use pace or a percentage of threshold pace as a tool to monitor interval intensity. 

Runners and swimmers often use targeted pace to reach a goal, for example, 5k race pace. 

But you still have to keep looking at your watch to know exactly what your pace is. 

While there are pace guides available (I have one to set up plans for runners), it is a challenge to understand how fast to run to be consistent throughout the interval.

If you’re a runner, you can go to a local track and time yourself per lap.

But the next three tools can be effective as you learn to monitor your interval intensity. 

The “Talk Test” is one way to monitor interval intensity. 

You can measure intensity by how well you are able to talk or sing.

The Talk Test has a surprisingly good correlation to heart rate and VO2.

In the Moderate Intensity zone, you are able to have a normal conversation, but you can’t fully discuss religion or politics because you can’t get enough air for that. 

You can sing but not the full chorus of Handel’s Hallelujah! 

In the Heavy Intensity Zone, you can talk, but not in complete sentences. 

Shorter efforts mean less ability to talk, longer efforts mean slightly more.

In the Severe zone, you can say individual words but only in an emergency, like “help.” 

You are, however, able to curse your coach in colorful language. 

The Talk Test, like all measures of interval intensity, takes some time to learn how your body reacts. 

Plus, I often train alone, and singing often brings funny looks!

Rate of Perceived Exertion (RPE) is another way to monitor interval intensity

Basically, you know how hard to go during intervals on a one to 10 scale effort scale.

A One is getting off the couch to get another cup of coffee. 

Ten is a “I think I’m going to die” effort. 

Typically, a moderate effort is about a five. 

It’s hard, but you can do the effort for long periods of time.

Targeting your aerobic capacity in the heavy zone can be between 6 and 8; and maximum (severe) efforts are 9 or 10. 

The challenge with RPE, though, is that how you feel is entirely subjective. 

If you aren’t used to pushing yourself, for example, a seven might feel like a 10. 

“Fast” or “fastest” is a third way to monitor interval intensity

In this method to monitor interval intensity, you have two speeds to do most intervals: fast and fastest.

Pick a speed that will allow you to stay in the heavy zone for as long as your target interval length.

“Fast” days are for building aerobic capacity in the heavy zone. 

“Fastest” days are for maximum efforts in the severe zone. 

What’s key is that you keep intensity consistent for the whole interval. 

You should try the same pace, but as you get more tired, the same pace will increase the intensity.

The end of the interval will feel really really challenging to keep up the intensity. 

And that’s what makes the intervals so challenging: You’re working hard, breathing heavy, and you still have minutes to go! 

Which system you’re targeting determines how hard you should go

Intervals in the heavy zone are tough, mostly because they are challenging and take a long time.

Your maximum zone intervals suck because they’re pretty much maximum effort. 

Learning how to monitor your interval intensity takes some time, regardless of whether you use a device or subjective tools like I’ve described here.

Even if you have devices, you still have to understand how much effort you need to put into each session.

Again, the key is to be consistent throughout the interval.

You want to start a little slowly and be able to maintain speed and intensity.

And there is so much to know about how long to do the intervals, how long to rest, and how many to do. 

But we’re not getting into that today!

Want to know more about what you can achieve? 

My purpose with Simple Endurance Coaching is to help everyday endurance athletes achieve their goals with more strength, endurance, and mobility. 

If you liked this article, please share it with others.

Sign up on the website to get a free copy of my e-booklet, “The Simple and Mostly Complete Guide to Strength Training for Everyday Endurance Athletes.”

You can also opt in to receive my weekly blog post about what works in endurance sports. 

Contact me or sign up for Virtual Coffee so we can discuss your goals, ask questions, and talk about making your endurance training more effective, fun, and Simple.


Paul Warloski is a: 

  • USA Cycling Level 3 Coach
  • RRCA Running Coach
  • Training Peaks Level 2 Coach
  • RYT-200 Yoga Instructor
  • Certified Personal Trainer