How to Interpret HRV – (Heart Rate Variability)
Reduce Stress and Increase Performance
You’ve spent months working hard on your base training and now your racing season is about to start. For most athletes, training is not something they spend a lot of time thinking about. This is because they might be doing it for fun, following a training plan, or paying a coach to create their workout routine.
Most coaches follow this coaching process to produce peak performance in an athlete:
- Determine an athlete’s strengths and weaknesses concerning event demands
- Manipulate the intensity and volume of training to produce specific adaptations
- 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 matters
As an athlete, what you probably notice the most during the build period is the ‘Manipulate’ column. Why? Because workouts get harder and longer, and you get tired!
In other words, your workouts get harder and longer as the year goes on, peaking at the end. Because you’re accumulating more fatigue than normal, you’re tired.
The temptation for athletes to train to the point of exhaustion is always a danger because they think that the more fatigue, the greater their performance. However, this is not the case. The amount of training stress an athlete can handle over time is directly related to their potential for performance. To achieve peak performance, you must carefully and specifically increase and decrease training stress to maximize the body’s ability to adapt. If you don’t train enough or if you train too much, you won’t be performing optimally.
How can athletes manage their training stress to perform their best on race day?
Understanding the Influence of Life Stress on Athletic Performance
Although the training process model highlights the importance of managing CTL, ATL, and TSB, it is more beneficial for athletes to understand, measure, and manage Total Life Stress.
TLS refers to the stress that an athlete experiences from all aspects of their life, including training, work, relationships, diet, environment, and lifestyle.
Although training is a key factor in an athlete’s performance, it is not the only one. Other factors affect an athlete’s ability to perform. Other stressors in life have an impact on performance, which can sometimes be greater than the effect of training.
The body cannot tell the difference between different types of stress, so if a person wants to get the most out of their training and perform well, they need to manage the stress in their life.
To manage something, however, you need to measure it. Thankfully, you can objectively quantify your TLS using heart rate variability (HRV). Although HRV is not an ideal way to model TLS, making adjustments to your lifestyle based on HRV data can improve your execution and adaptation during training, increasing the likelihood of better performance on race day.
What is Heart Rate Variability?
If someone’s heart rate is 60 bpm, that means their heart is beating 60 times every minute. The heart is not a perfect metronome, although it is very impressive. He’s saying that the 60 beats are not evenly spaced out within that minute. The timing between each heartbeat can be slightly different because the heart rate speeds up when a person inhales and slows down when a person exhales. That fluctuation is referred to as heart rate variability.
Fluctuations in stress levels can be measured in milliseconds and can give a lot of information about the body. HRV is a way to measure how the body is responding to stress. A person’s HRV is high when their body is experiencing low internal stress levels. A low HRV means that the body is under a lot of stress. Many different factors can cause internal stress. Many things can cause stress on the body, such as physical activity, mental stress, illness, poor diet, and drug/alcohol use. HRV can be used by athletes to estimate how ready their bodies are to take on the physical strain. There are a few things you can do to improve your HRV, including getting in better shape, reducing your training for a short period, getting more sleep, and leading an overall healthier lifestyle.
How does HRV work?
The autonomic nervous system (ANS) controls a person’s heart rate subconsciously. The autonomic nervous system is responsible for automatically regulating heart rate in response to the body’s need for more or less oxygen. The autonomic nervous system (ANS) is made up of two branches that work in opposite ways: the sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS).
The SNS is the branch responsible for the human fight or flight response. The SNS is designed to divert the body’s resources to the brain, heart, and working muscles to be as mentally alert and physically ready for action as possible.
Actions of the SNS include increasing heart rate, cardiac output, breathing rate, and blood pressure; diverting blood to the brain and muscles and away from other internal organs; and increasing glucose and fatty acid mobilization and metabolism. The SNS is always active when the body is going through physical or emotional stress.
The PNS is often referred to as the side of the ANS that is responsible for rest and digestion. It guides the body to a state of rest. The PNS can help to lower heart rate, breathing rate, and blood pressure. The digestive process and absorption of nutrients are slowed down during periods of high stress. The activity of the parasympathetic nervous system is highest when the body is calm and relaxed.
Heart rate variability is determined by which branch is more active. The more sympathetic activity there is, the stricter the control over heart rate. This means that heart rate becomes less variable, and HRV decreases.
When the body is relaxed, the SNS has less control over heart rate and HVR increases. There is a tug-of-war between the two branches of the ANS.
Good health needs to have a balance between the two branches of the ANS. The branch that is in control will vary throughout the day. At night during sleep, the PNS dominates. Therefore, HRV will be higher. As people become more active and stressed during the day, their heart rate variability (HRV) will decrease.
HRV typically returns to normal levels within 24 to 48 hours after exposure to a stressor. Although it is not common, during times of great stress it is possible to become stuck in a state where the sympathetic nervous system is dominant. People who are left alone for long periods can experience negative health effects, such as a weakened immune system and systemic inflammation. Athletes who drink coffee before working out will not see the same fitness gains as those who don’t. Measuring your HRV every day gives you insight into how your body responds to training stress.
How to Measure HRV
One way is to use a device that you attach to your chest, and the other way is to use a finger sensor. The two most common ways to measure HRV are with a chest strap device or a finger sensor. Both require mobile applications. A heart rate monitor that straps to your chest is one way to measure your heart’s electrical signals. Photoplethysmography (PPG) is a method used to detect the heart rate optically through the skin. Most fitness trackers, including the Apple Watch and Whoop bands, use PPG technology. Some brands use a finger or ear sensor, while others use the camera on a cell phone.
The user must sit or lie calmly for a few minutes to get an HRV measurement. The device will monitor heartbeats during this time. The average inter-beat variability is given in milliseconds depending on the technology being used.
Each person’s average HRV range is different, but most people’s HRV ranges fall somewhere between 30-100ms. Males typically have higher levels of this than females, and younger people typically have higher levels of this than older people. This is because as you become more physically fit, your body becomes better at regulating your heart rate.
Looking at a single day’s HRV reading doesn’t tell us much, but if we look at how HRV changes over time, we can get a better idea of what’s going on. HRV, or heart rate variability, is a measure of the time between each heartbeat. When a person is stressed, their HRV typically decreases. When someone experiences a downward trend, it means that their body is having difficulty bouncing back from stress. An upward trend is a good sign that someone is getting better or getting in better shape.
Validity & Reliability
HRV isn’t a perfect metric. The reliability of different systems can vary greatly. The way measurements are taken and the time of day can have a big effect on results. To be accurate, the medicine must be taken every day at the same time. It is essential to be as consistent as possible.
The ideal time to measure HRV is in the morning, right after you wake up and before you’ve accumulated any physical or mental stress. Some of the PPG wearable devices do this automatically. However, most HRV monitoring systems require the person to physically take a reading themselves. If the user is consistent with the system, any device should be able to provide accurate enough information to make educated decisions, even though the system is not perfect.
Key Factors That Affect Heart Rate Variability and Stress
The graphic below shows “Rider Ability” broken out of the Training Process framework and expanded into more specific subcategories. Many subcategories and factors can contribute to your TLS. This is just a starting point to help you determine what lifestyle changes you can make to improve your TLS. What lifestyle factors hold you back the most? What are some ways you can reduce stress so that you perform better?
The answer for you is individual. I often see lifestyle factors holding athletes back in the build period. These include life, sleep, nutrition, and alcohol consumption. We’re going to explore some of the most common HRV trends and learn how reducing stress can improve your performance.
Life
As a coach, the second most important rider ability that affects performance is “Life”. Why? Alan Couzens said that the load that an athlete can absorb is determined by the type of life that they want to live.
Most athletes are not paid to race. Instead, your priorities look something like this:
This means that your ability to train effectively is dependent on your ability to maintain a stable balance of priorities, with training being a lower priority. Your priorities in life can contribute to stress, which can in turn negatively impact your training if it’s not managed properly. Be aware of potential stressors in your life, such as your relationships, career, and financial responsibilities, so that you can address them before they cause too much stress.
Nutrition
Many endurance athletes aspire to achieve “race weight.” Your dieting approach and timing can make it difficult to train, adapt, and perform well.
Although small changes in nutrition may not have a noticeable effect on HRV, more significant changes are often quite noticeable.
You should never experiment with your diet during the build period when energy demand is highest.
Alcohol
The athlete’s hangover is telling them that alcohol tanks recovery and performance and this is confirmed by HRV. Although exercising does have some benefits for your health, it’s not realistic to think that it will make up for the negative effects of drinking alcohol.
The act of drinking alcohol does not nullify the stress caused by other factors in your life, it only magnifies it. If you drink alcohol excessively, you will never be able to train or race as well as you could because you will never fully recover.
Sleep
If you’re not getting enough sleep, it will limit your potential and make it harder to make progress. Sleep is the most important driver of recovery. If you don’t get enough sleep, you agree to make it harder for yourself to adjust to your workout routine.
Start by evaluating your sleeping habits if you’re feeling chronically fatigued. Some athletes do have chronic sleeping issues, or they are so busy that they really don’t have time to sleep more. In many sleep-related cases, bad sleeping habits are to blame. This can include things like staying up late to watch Netflix without realizing it because of the show’s automatic “next episode” feature. The quality of your build period will improve quickly if you can improve your sleep.
Conclusions About HRV, Stress, and Athletic Performance
To achieve the best performance from your training, you need to do more than just complete your workouts. You also have to manage your Translation Lisa to maximize your adaptation.
To do so, watch your HRV trend. Whether a given quantity is stable and increasing or variable and decreasing can be determined by observing its behaviour over time. What are some lifestyle factors that could be causing a decrease in HRV if the trends are poor? 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, such as sleep, nutrition, and stress levels.
