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Heart Rate, Hydration & Cardiac Drift

Heart Rate, Hydration & Cardiac Drift

We hear a lot about the importance of hydration. Did you know that hydration, or the lack thereof, has a huge impact on your heart rate? Which in turn will decrease workout productivity, performance and recovery. It has been shown that dehydration can increase cardiac drift. What is cardiac drift? Cardiac drift means that, over time, our heart rate is going to increase, even if we remain at the same level of effort/intensity. Let’s use running as an example. Let's say that an individual is going to run and 8:00 pace per mile and they are going to run 5 miles. Even though the pace will not change over the next 5 miles/40 minutes, the heart rate will continue to increase over time. The heart rate, at the exact same pace, will be higher at mile five as compared to mile one.


How does this relate to your 9Round workout (and all of your workouts) and how can you maximize your 9Round work out by managing cardiac drift? Let's look at it like this; let's say that the heart rate climbs quickly in round one (early in your workout) and you find yourself already in the red. And remember, the goal is to stay in the green and yellow so that we maximize workout productivity. You will probably notice that, in a scenario like this, it becomes somewhat of a struggle over the next eight rounds and almost impossible to get that heart rate back down, right? Short of stopping completely or lying down on the ground, you continue to find your heart rate in the red, despite slowing the effort and going at a pace that seems fairly conservative.


Therefore, one of the main keys to success is to manage cardiac drift during your 9Round workout. Knowing that the heart rate, naturally, is going to climb over the next 30 minutes, the very first second of the very first round becomes critical. Now, I don't want to give a mixed message. Managing heart rate properly and managing cardiac drift, in no way, means that we are going to go easy or take it easy in the early rounds, not even close. Rather, we want to use proper energy economy and energy management. We don't want to burn all of our matches early in the 9Round workout.


As we gradually and progressively build into each round and we properly manage cardiac drift and we keep the heart rate gradually building into the blue, green and yellow, we are going to put together an amazingly productive workout. We will find ourselves being able to work out, nonstop, without having to pause due to cardiovascular drift and/or muscular fatigue. We will find ourselves getting stronger and stronger and going faster/harder as the rounds progress. This should be the complete opposite of the example above. In the example above, when that heart rate gets jacked up into the red in the very first round, we find ourselves having to slow up and ease up as the rounds progress.


In addition, hydration directly impacts cardiac drift. During prolonged exercise, stroke volume decreases. Stroke volume is the amount of the blood the heart pumps with each beat. In a study on athletes published in the Journal of Applied Physiology, it was found that athletes entering a workout well hydrated showed less cardiac drift as compared to those who were dehydrated. When it comes to hydration, what we have to understand is that it is not just water that hydrates us but it’s also our everyday nutrition. Individuals who choose to follow food fads and diets and cut out carbohydrates can find themselves dehydrated (and this is also why they lose weight so quickly [and then gain it right back]). Therefore, if our water intake frequency, timing and/or nutrition is off, this can lead to dehydration. And as a result, we can enter a workout dehydrated, stroke volume will decrease, core body temperature increases and this can accelerate the cardiac drift. Not only does this lead to a less productive workout, but it can also lead to reduced recovery (and this negative cycle continues into the next workout as well).


In summary, we can look at proper heart rate training as energy management, hydration management and fueling management. Let's say that we have "100 units of energy" to use during a workout. Well, we don't want to burn up all of those units of energy (too high of a heart rate), too early (this will happen if we are dehydrated and/or drive up the HR too quickly). Because if we do, we are not going to maximize our workout productivity. Rather, we want to be properly hydrated and fueled and then gradually and progressively use those units of energy so that we continue to get stronger and stronger throughout each round. When we properly manage our energy and we properly manage our heart rate, it's amazing how each workout becomes so productive. And then, over time, results continue to follow. This type of energy management and heart rate management is critical for success, no matter what the goals. Whether the goal is body transformation, improved health and fitness or improved athletic performance, managing cardiac drift will help to bring about incredible results!



  1. Cardiovascular Drift During Prolonged Exercise: New Perspectives
  2. Influence Of Graded Dehydration On Hyperthermia And Cardiovascular Drift During Exercise


Workout Smart, Eat Right, Get Results™!


Dr. Rick Kattouf II

2x Best-Selling Author

9Round Nutrition Coach

Named One of America’s PremierExperts® in Nutrition & Fitness

Named One Of The World Fitness Elite® Trainers Of The Year