In this article we will examine some awesome new research on CrossFit heart rate training. Traditionally most Crossfitters, and functional fitness athletes, have ignored heart rate based training in favor of the “harder is better” approach. This is in stark contrast to the norms of traditional endurance training methods. After reading this article it should be clear that training hard is not always the same as training smartly!
CrossFit has been around for over two decades, and I’ve been training, coaching, and writing programs for these athletes for over 18 years. Not to date myself, but I started CrossFit before the butterfly pull up was invented. I know, I know, I’ll see myself back to the high-intensity training nursing home.
I bring that up to point out that I’ve seen quite the change in programming styles, across nearly two decades. Initially most CrossFit athletes only did the WOD from the main website. It was basically random, with some strength days, and mostly WODs comprising the bulk of the programming.
As the CrossFit Games increased in popularity, the importance of strength work became apparent, specifically for the sport of CrossFit. Most gyms and athletes started to routinely engage in strength work, and then a WOD or metcon training session afterwards.
Currently, we’re seeing another transition, where the best CrossFit athletes are seeing the benefit of training like olympic level endurance athletes. This is where our current piece of research comes in. Check out the overview below.
CrossFit Heart Rate Training : Research Overview
- Polarized training is equivalent to traditional CrossFit Training
- Polarized athletes report fewer injuries, and increased recovery
- Reduced training intensity may allow for increased training volume
- Traditional CrossFit training may be better suited for peak season
This research is very important, even though they found that both groups increased performance at roughly the same pace. As you’ll see, once we get into the details, polarized training is likely to be a more efficient method of increasing training performance, compared to maximum heart rate training. Let’s get to the research.
Before we do that, you should join our Email list. We’ll send you some great free guides on strength training and fat loss. You’ll also get the weekly article sent directly to your mailbox.
CrossFit Heart Rate Training Research
This research study titled, “Six weeks of polarized functional interval training with large training load reductions does not affect performance gains compared to traditional workouts,” examined lower heart rate training for CrossFit athletes.
The researchers chose 30 experienced CrossFit athletes (15 male and 15 female) and split them up into two different groups. Initially, they tested both groups for their lactate threshold, VO2 max, as well as strength values in the squat, bench, and overhead press. Lastly, they had them perform the benchmark WOD Jackie.
Based on this data, they had both groups perform the exact same training plan, over six weeks. The traditional CrossFit group followed a fairly standard workout program, where the CrossFit workouts were done at max effort 4 times per week. Obviously this group had a much higher heart rate in every session.
The polarized group did the exact same training protocol; however, they were restricted by keeping their heart rate within a tightly prescribed training zone, using a heart rate monitor for each session. The polarized group performed most of their training under lactate threshold 1, better known as Zone 2 or the aerobic threshold.
If you’re new to Zone 2 training, you can read all about it here. Long story short, it’s a great way to increase endurance and improve your CrossFit WODs. If you want an awesome functional fitness program with smart Zone 2 training paired with WODs, metcons, and heavy lifting, then check this out below.
The rest of their training was performed above lactate threshold 2, otherwise known as max HR. Obviously, this is above their anaerobic threshold. Practically speaking the athletes were only allowed to go max effort on one WOD per week, with the other three being controlled by live heart rate monitoring.
The researchers quantified this total load using a method called TRIMP, or training impulse. Simply said, this is a metric where each minute in a certain heart rate zone is given a weight. You get a 1 in easy heart rate zones, a 2 for moderate zones, and a 3 for max effort red zone training. As you would expect, working out at max heart rate equals a higher TRIMP score.
Lastly, the athletes self reported their recovery, injury status, and overall well being. Lets take a look at the results.
CrossFit Heart Rate Training Results
This is where you expect me to tell you that the polarized group crushed the traditional group when they remeasured their Jackie scores, and lifts. Well, think again! They actually performed almost exactly the same, with no significant differences, after six weeks of training.
The key difference was that the polarized training group reported much fewer injuries, less soreness, and increased readiness to train.
You can see in the graphic that the TRIMP scores were significantly lower in the polarized group. They spent way less time with high heart rate training, focusing primarily on training their aerobic system. As a result, they reported feeling good about 90% of the time, compared to about 40% of the time for the normal CrossFit training group.
Some of you might be asking, “What were the performance outcomes?” Well, I’m glad you asked. You’ll find those below.
You can see that the pre and post test scores all moved in the same direction, by roughly the same amount. There are some differences, but they were not statistically significant. As you’ll see in the next section, this research result is great news for hard training functional fitness athletes.
Remember if you want your own polarized training program, you can find it below. It’s designed to build your aerobic capacity and top end strength at the same time.
Discussion
There are two clear implications of this research. First, you can obtain the same results with a much easier training program. I find as a coach that athletes always want to go as hard as they can, in the mistaken belief that that’s the fastest way to progress. While that may be true in the short term, it absolutely won’t work over months and years. There’s a reason heart rate zone training is used by all serious endurance athletes.
The second implication is that for those that really do want a maximum fitness level, you would be able to accrue much higher training volumes using a polarized approach, compared to traditional CrossFit methods. Overall training volume is perhaps the best predictor of exercise performance, when doing high intensity training with functional movements.
I would love to see a version of this study where they equalize the TRIMP scores, which would allow for a higher training volume, utilizing polarized training. I would assume those athletes would have much better performance, with more low heart rate training time.
The researchers did note that it can be difficult to attain a true moderate intensity level with a workout of the day. As anyone can tell you, it takes a few minutes for your heart to really reach HR max. They mentioned that these heart rate responses can also be kept lower simply by going at a certain rate of perceived exertion or session RPE. This would be keeping your effort to something like a 6 out of 10.
Final Thoughts
It’s important to understand that you still need hard, gut busting effort, during some portion of your training. You cannot perform your best if you have no familiarity with your current limits. This research simply points out that pushing your limits all the time isn’t a smart training plan.
This makes sense, especially when you consider how we program strength training. You spend quite a lot of training time in the 70-80% range. Only after weeks of this do you get to start playing in 90% plus. While this metaphor doesn’t exactly map onto this type of aerobic training, it’s close enough.
You need to build exercise volume, increasing cardiac output, over weeks and months. Once this is built, you can enter a period of pushing your pace more often. This pushes your peak performance higher. After a while, you would then return to building your aerobic base even larger. This cycles repeats endlessly for high performing athletes.
If you liked this article, share it with someone who can benefit from smarter training. Don’t forget to join the email list below. Now get out there and get training!
The opinions and information expressed in this article are solely those of the author and are not affiliated with any corporation, group, public or private entity. This web site is not endorsed by, directly affiliated with, maintained, authorized, or sponsored by Crossfit Inc, Zwift, or Assault Fitness. All product and company names are the registered trademarks of their original owners. The use of any trade name or trademark is for identification and reference purposes only and does not imply any association with the trademark holder of their product brand. Furthermore it’s recommend that you consult a medical doctor prior to exercise. Always exercise under the guidance of a qualified professional. All links to Amazon are affiliate links.
