All About Heart Rate-Based Training - Coach Tip Tuesday

Last week’s Coach Tip Tuesday dove into why fitness devices are not as smart as they seem at face value.  While this is true, it is also true that there are some technologies and devices that have a worthwhile and valuable place in endurance sports training.  This week kicks off a mini series of Coach Tip Tuesdays where we will discuss certain technologies and how athletes can best implement them.  First up: Heart Rate-Based Training.

What is Heart Rate-Based Training?

Heart Rate-Based Training is exactly what it sounds like; it’s training that is based off of the athlete’s heart rate.  Heart rate is the body’s response to any stress that is placed on it.  In training, this means that we can see how the body is responding to training by observing heart rate.  Using individualized training zones, an athlete can design training based on their own heart rate.  Their training is thus based on an internal load, rather than an external reference (such as pace or speed).  Plainly put: Heart Rate-Based Training is a very individualized way to approach endurance sports training.

How to Implement Heart Rate-Based Training

Successfully implementing Heart Rate-Based Training is a bit of a process:

1. Ensure that you are accurately able to measure your heart rate during exercise.  Use this same measuring device throughout the entire process of Heart Rate-Based Training.
2. Determine your heart rate zones via testing.
3. Design training around those heart rate zones.
4. Stick to a training plan designed around heart rate zones consistently for at least three months.

Accurately Measuring Heart Rate

In order to train by heart rate, an athlete does need to have a properly functioning heart rate monitor.  As we discussed last week, it’s important to ensure that the data being collected is accurate because bad data is worse than no data.  When it comes to heart rate data collection, there are a few things that are true:

• The further away you get from the heart, the more difficult it is to accurately measure heart rate.
• Optical (light-based) heart rate sensors are very desirable because of their ease of use (meaning that they’re easy for the user to wear), but they are more prone to errors than chest-based heart rate straps are.
• Optical heart rate sensors must be worn in very specific positions with very specific levels of tightness.
• Optical heart rate sensors measure heart rate based on the volumetric changes of the components that make up the cardiovascular system, namely the veins and capillaries under the skin.  Basically, these sensors measure heart rate by visually tracking how much the veins and arteries expand and contract.
• Chest-based heart rate straps measure heart rate by detecting the electrical signals originating from your heart.
• Chest-based heart rate straps must be wet or used with certain types of electrode gel to make sure that the sensor can pick up the electrical signals.  This is because the electrical signals coming from our heart are carrying through our body fluids onto the skin.  The electrodes in the sensor can detect these electrical signals with the assistance of water and/or electrode gel.

Consistency is extremely important in all endurance sports training, but it’s especially important in Heart Rate-Based Training, especially when it comes to the measuring device.  The same measuring device must be used for both the test and throughout the training in order to ensure that the data is accurate and comparable against each other over time.  Simply put, you cannot use a chest-based heart rate strap some days and an optical heart rate sensor on others because they do not measure the same way.

Determine Your Heart Rate Zones

In order to successfully implement Heart Rate-Based Training, you must determine your own personal heart rate training zones via threshold testing.  These zones vary by sport, so if you are a multisport athlete, you will need to do separate testing for each sport you train in.

It’s extremely important to understand that the “default” training zones established by algorithms (read: by Garmin Connect or any other training software or device) are not accurate.  Ever.  As a general rule, I don’t deal in absolutes, but this is one instance where I will.  No algorithm can ever accurately determine what your personal heart rate zones are.  You must do a threshold test to accurately determine them.

It’s also important to note that any “quick and easy” calculators or formulas you find online promising to determine your threshold heart rate or your training zones without a test will also be inaccurate.  Like so many things in life, there isn’t a shortcut or quick and easy solution here.  You must do the hard thing and do the test.

A threshold test can vary slightly from sport to sport in terms of the specific details of the workout, but the basic premise is the same: Conduct a 10-15 easy warm-up, and then go as hard as you can sustain without stopping or resting at all for at least 20-30 minutes.  The data gleaned from that sustained harder effort can then be used to calculate your personal training zones.  (For more details on how you can determine your own training zones, please connect with me.)

Threshold testing like this is one of the only times in training where the workout must be completed exactly as it is planned.  If any mistakes or modifications are made, the data is useless and must be discarded.  Remember: The only way this type of training works is if the baseline data is accurate.  So, if they cannot complete the test exactly as planned, the athlete needs to redo the test, but there’s a waiting period involved.  Since these tests do ask athletes to go their hardest, there needs to be a period of recovery before the athlete will be truly ready to go their hardest again.

Design Training Around Heart Rate Zones

The next step is to design training that is based off of your own personalized heart rate zones.  This means that you will complete workouts while monitoring your heart rate and staying within the prescribed zone as planned.

Since heart rate is the body’s response to stress, it is not instantaneous.  This means that the stress (aka the intensity) of the workout must be implemented, the body will sense that stress, and then heart rate will respond.  As a result, it may take a bit of time (sometimes as little as a minute or two, sometimes much longer than that) for heart rate to rise.  So, if you are doing an interval prescribed in a certain zone, it’s important to know that you won’t instantaneously be in “compliance” with that zone; you will need to give your body time to work into it.  For this reason, knowing the Rating of Perceived Exertion (RPE) levels that correspond with each Heart Rate Training Zone is really important, because every Heart Rate-Based Interval is ultimately going to start with RPE.

Stick to it for at Least Three Months

In order for athletes to derive the benefits of Heart Rate-Based Training, an athlete must stick to a training plan designed around heart rate consistently for at least three months.  When I say “a training plan designed around heart rate,” I mean that at least 95% of the workouts in those three months must be designed around heart rate and completed by sticking to the prescribed heart rates in that workout.  Doing this type of training in one workout once a week will not yield the intended results; it must be done consistently in almost all workouts.

In my experience, this is - by far - the biggest challenge for athletes, and it’s where most athletes “fail” at Heart Rate-Based Training.  It’s not uncommon to hear “Heart Rate-Based Training didn't work for me” and the root cause of that statement is that the athlete wasn’t willing to stick with the plan day-in-and-day-out for at least three months.

During this time, athletes will have to go slower than they are used to to stick to their training zones.  Doing so enables them to get their bodies to adapt to the training and develop their aerobic system without overstressing other systems in the body, such as the muscular and skeletal systems.  Over time, doing this will train the body to go faster while operating at a lower heart rate.  This type of economy and efficiency is really excellent in endurance sports, especially in long course events such as half marathons, marathons, IRONMAN 70.3 races, or IRONMAN races.

The Benefits of Heart Rate-Based Training

Heart Rate-Based Training is extremely useful for helping athletes develop self-awareness.  Over the course of my coaching career, the most valuable use of Heart Rate-Based Training is to help athletes learn what “easy” really feels like and what “slow” really is.  By teaching athletes this, Heart Rate-Based Training can reduce the risk of fatigue and overtraining.

On the other side of the coin, this type of training can be really useful to help push athletes who are naturally conservative into the training efforts and zones that are necessary in order to elicit adaptations in the body and therefore make gains in endurance sports.  For athletes who are afraid to push themselves, Heart Rate-Based Training can provide an effective and safe framework for them to do so.

Heart Rate-Based Training can enable athletes to more effectively track their effort in interval workouts (workouts where there are intervals completed at a higher intensity).  In my experience, this is especially valuable for tempo workouts, where dialing in on the proper exertion level is really important to benefit from the workout.

This type of training can also help athletes moderate how much external factors (such as wind, heat, humidity, other stressors) impact them during a workout or race.  This might be the most fun benefit of Heart Rate-Based Training.  It’s effectively cross-pollination; Heart Rate-Based Training trains athletes to moderate and control their heart rate, and this skill is not limited to controlling their heart rate in this exact scenario.  When other stress is placed on the body (such as heat or humidity), the athlete is already equipped with tools for how to manage it, and thus the stressor is not necessarily as impactful on them as it might have otherwise been.

The Limitations of Heart Rate-Based Training

Like all things, Heart Rate-Based Training does have its limitations.  One of the biggest ones is paradoxical, because it’s the same reason why Heart Rate-Based Training is valuable as a training tool in the first place: Heart rate is the body’s response to stress that is placed on it.

It’s important to note that heart rate will represent a response to any stress that is placed on the body, not just endurance sports training.  This means that a whole host of other stressors can (and will) impact heart rate, including (but not limited to):

• Insufficient sleep
• Work Stress (such as a big project or looming deadline)
• Life Stress (such as a move, job change, marriage, birth, etc.)
• Family Stress (such as a fight with a spouse or a surly teenager)
• Heat
• Environmental Factors (such as dogs chasing you in the middle of a workout, cars almost hitting you on a bike ride, etc.)
• Wind

Because of this, it’s important to continually hone self-awareness so you can accurately determine when other stressors are in play that may be impacting heart rate.  When this is the case, it’s important to modify your strategy and use a combination of Rating of Perceived Exertion (RPE) along with heart rate to guide your training for the day (or your race plan if there are additional stressors in play on race day).

The Bottom Line

Over the course of my career, I have helped dozens of athletes successfully implement Heart Rate-Based Training.  I’ve also personally implemented it for over 15 years now in my own training.  It’s an extremely effective tool for honing the skill of self-awareness and it’s helped many athletes unlock great potential and execute strong workouts and races.  It isn’t necessarily simple, there’s definitely a learning curve involved, and it does take a long time before the return on investment of training this way is seen.  But for athletes willing to give it a try and who stick with it, it really can be a game changer.