Using HRV to reduce stress and improve training

The top athletes having been using HRV for the past couple of decades to improve their training to higher performance levels. Here’s how they do it.

After putting in months of diligent base training, the racing season approaches. Most athletes follow a training plan. The basic training process isn’t complicated.

  • Assessment: Ability and event demands;
  • Planning: Volume and intensity;
  • Manage: ATL / CTL / TSB;
  • Outcome: Performance.

Generally coaches follow this process to produce peak performance in an athlete:

  1. Assess an athlete’s strengths and weaknesses with respect to event demands;
  2. Plan the intensity and volume of training to meet the goals, adapting as the metrics reveal how the training and external factors are influencing the numbers;
  3. Manage Chronic Training Load (CTL, or Fitness), Acute Training Load (ATL, or Fatigue) and Training Stress Balance (TSB, or Form) to produce peak performance when it’s needed.

Successful athletes understand the metrics and look for the indications that the intensity and column of exercise is working. They also look to see the impact of external factors on their training, and make adjustments accordingly.

During the build period, workouts get harder (intensity goes up), and sometimes the duration (volume) of workouts also goes up, which results in the highest (or nearly the highest) training load of the year. Because the athlete is accumulating more fatigue than normal, they’re tired.

The temptation for athletes to train themselves ragged is always a danger because they think that the more fatigue, the greater their performance — wrong! The chronic accumulation of training stress (iCTL) is an athlete’s potential for performance. Achieving peak performance requires careful, specific loading and unloading of training stress to maximize the body’s adaptation. If an athlete trains too much or too little, their performance is suboptimal. 

So, how can an athlete optimally manage training stress through the build period to produce their best performance on race day?

Understanding the Influence of Life Stress on Athletic Performance

CTL, ATL, and TSB are all worthy things to know and manage; but as an athlete, you’re much better off understanding, measuring, and managing something the training process model doesn’t mention – Total Life Stress (TLS).

Total Life Stress is all of the stress an athlete experiences in life regardless of source, which can include training, work, relationships, diet, environment, lifestyle, etc. Athletes sometimes struggle to realise (or admit) this, but training stress isn’t the only factor affecting performance. Every other stressor in life affects performance as well — sometimes even more than the training itself! The body doesn’t differentiate between the source of stress, so stress outside of training is a crucial variable to manage to optimise training and achieve peak performance. 

To manage something you need to measure it. Thankfully, you can objectively quantify your TLS using heart rate variability (HRV). While HRV isn’t a perfect way to model TLS, adjusting one’s lifestyle to in response to HRV can produce better workout execution and adaptation in the build period, which increases the chances of better performance outcomes on race day.

How to Interpret HRV

Understanding how to interpret HRV can help an athlete in many ways.

A healthy, resilient athlete will enjoy a high, relatively unvarying HRV combined with a stable, low resting heart rate (RHR). An unhealthy, sick/overtrained/injury-prone athlete will have lower, volatile HRV readings.

Here are a few additional HRV facts to keep in mind:

HRV does not directly predict performance; instead, it’s a window into fatigue. You can regularly perform well even when fatigued (e.g., if you wake up with a low HRV reading), but remember that for adaptation to occur, you must recover. (HRV Health’s recovery metrics which are a by-product of HRV are the way to predict performance).

If HRV remains within a normal range after you complete a hard workout, it’s a great sign! A stable HRV demonstrates that your nervous system is absorbing the stimulus.

HRV is a reflection of the nervous system, so it won’t necessarily correlate with other training stressors, like delayed onset muscle soreness (DOMS).

When athletes begin to measure HRV, they naturally wonder how their score compares to that of other athletes. While this can be useful, gender, age, health, and fitness levels complicate direct comparison. For reference, here’s a review of HRV demographics to see how your HRV values compare.

While more rare, a single HRV reading that is much higher than normal can also indicate fatigue.

The fun part about monitoring your HRV is that you can start to experiment on yourself. Once you have an HRV baseline, you can start altering your habits to decrease TLS and then confirm if those changes are working by monitoring trends in your HRV and RHR. If you consistently reduce your TLS, you’ll be able to sustain and adapt to the high training load of your build period and perform better on race day. 

The HRV Health Platform shows two stress metrics, the Stress Index and Stress. The two metrics are the result of two competing algorithms, and we display both for completeness. With the Stress Index, a figure over 150 is a sign of excess stress. For the Stress figure, 10 is considered to be high. Nevertheless, once you have established your own baseline, this is a better indicator of your personal stress levels, and deciding whether there is cause for concern.

Key factors that affect Heart Rate Variability and Stress

Ability can be broken out of the Training Process framework and expanded into other subcategories. The subcategories and factors within the subcategories are not exhaustive, but they’re a useful starting point to determine what lifestyle factors contribute the most to your TLS. What lifestyle factors hold you back the most? How can you reduce the stress related to these factors so that your TLS decreases, allowing you to perform better?  

The factors affecting performance individual to each athlete. These include lifestyle, sleep, nutrition, and alcohol consumption. Let’s dive into each of these topics to see common HRV trends and how you can reduce related stress for better performance. 


Outside of physical attributes, Lifestyle is the most important subcategory of ability that affects performance Why? Alan Couzens put it best: “The athlete chooses the type of life they want to live and that, in turn, determines the load they’ll be able to absorb.”

If you’re like most athletes, you’re not paid to race. Family, relationships and work come ahead of training.

Consequently, your ability to execute and adapt to training – especially the intense, demanding training in a build period – depends on the stability and balance of your priorities that take precedence above training. These priorities include your relationships, career, financial responsibilities, etc. If you can identify potential stressors in these areas, you can develop a plan to mitigate the issue before it adds enough stress to your TLS that it negatively impacts your training in the build period.

For example, during a build period, your relationships with significant others and friends tend to get pushed aside by training and racing demands, leading to resentment and deterioration. 

Your HRV can reveal some of the stress of that friction. 


Achieving “race weight” is an almost universal aspiration for endurance athletes. While there’s nothing wrong with optimizing your body composition, your dieting approach and timing can undermine your training, adaptation, and ultimately your performance.

While small nutritional changes aren’t always apparent in HRV, dramatic nutritional shifts are. 

If you make a change to your diet with the intention of losing weight look for signs that this is undermining your performance. A ride in RHR and a consistent drop in HRV are clear indicators that the diet is having a negative impact.

There’s a time and place for you to experiment with your diet, but it should never coincide with the build period when energy demand is highest. You won’t know whether it’s the diet or the intensity of the training which is impacting your metrics.


According to a study published in Medicine & Science in Sports & Exercise, if you’re an endurance athlete, you’re more likely to drink alcohol. While athletes often delude themselves into thinking that alcohol doesn’t negatively affect performance, HRV objectively confirms what an athlete’s hangover is already telling them – alcohol tanks recovery and performance.

Recovery is even more critical to your success in the build period because of training load demands. Many athletes – masters athletes, in particular – regularly consume enough alcohol to negatively affect their recovery.  

The two most common reasons cited for drinking are moral licensing and stress relief. Moral licensing is a phenomenon whereby we falsely believe that one good action can excuse or negate a bad action. For example, imagine you train for five hours and then drink four beers because you ‘trained a lot today’. 

While there’s some truth to the health buffering effects of training, it’s wishful thinking to believe that your exercise will cancel out your drinking. It’s not an exaggeration to point out that when you drink, you’re essentially poisoning yourself. Your body drops everything to process the alcohol and flush it out of your system before it resumes any other tasks, like replenishing your glycogen stores or repairing all the muscular and metabolic damage you created during your five-hour training day. In other words, drinking isn’t canceled out by the stress of your exercise; it adds to the stress of your exercise. If alcohol consumption is chronic, you will never train and race to your potential because your recovery is always compromised. 

Second, most athletes don’t train or race for a living and have demanding, stressful lives. To relieve the stress, they drink. While that’s understandable, it’s easy for alcohol to become their only stress coping mechanism while never working to reduce the cause of the stress or find different ways to relax. 

How can you reduce your alcohol intake so your training and recovery during the build period improve? 

Begin a sober challenge: Challenge yourself to the equivalent of “Sober October”.

Switch to non-alcoholic: Drinking non-alcoholic beverages has become increasingly acceptable, with the result that it’s an exploding industry offering non-alcoholic beverages with more than passable drinkability. 

Embrace moderation: If you aren’t open to teetotaling, consider sticking to CDC guidelines, which recommend a maximum of two standard drinks per day for men and one for women. Simply moderating your consumption can sometimes trigger a massive improvement in execution and adaptation.

If you aren’t open to changing your drinking habit, that’s fine – just realize regular consumption of alcohol will have a detrimental effect on the quality of your build period and, eventually, your performance. 


Lastly, poor sleep will always limit your potential, but it can especially hinder your progression in the build period. Sleep is the most important driver of recovery. If you skimp on sleep, you are unwittingly (or wittingly!) agreeing to compromise your ability to adapt to your training. 

Conveniently, many inexpensive devices wearable devices collect extensive sleep data. Many are not very reliable, so look at the reviews to see what works. We have covered this subject in another article.

On the HRV & BP result page, the HRV Health Platform allows you to enter you sleep metrics and see how your sleep quality is affecting your performance.

ds based on sleep patterns

Evaluating your sleeping habits is always a good place to start if you feel chronic fatigue. It’s true that some athletes have chronic sleeping issues or lead such busy lives that they really can’t sleep more. Still, in many cases, the main culprit is an obvious bad sleeping habit. A good sleep will will provide you with guidance on how to improve your sleep, and with that, your performance. If you can improve your sleep, it’ll quickly benefit the quality of your build period.

Conclusions About HRV, Stress, and Athletic Performance

Achieving the greatest performance from your build period requires more than knocking out your workouts. You also have to manage your TLS to maximize your adaptation.

To do so, watch your HRV trend. Is it stable and increasing, or is it variable and decreasing? If your HRV trends are poor, what lifestyle factors might be contributing to the decrease? What adjustments can you make to produce better results?

The key to your breakthrough in performance might not be perfectly executing your workouts, but instead managing all of the lifestyle factors that training and adaptation depend upon.