Why Can’t I Go To That Dark Place?

Why Can’t I Go To That Dark Place?

Eric Roux, MS, LAT, ATC, CF-L1

dark place

Have you ever been working out and hit a wall? A wall that for some reason you can’t conquer. Regardless of how hard you try, how fit you are, you feel as if you just cannot go on. Legs or Arms burning and aching… it’s almost the norm. Some people are able to conquer this wall, fight through this signal of extreme physical strain. In the CrossFit realm this is called having an “Engine” or being able to go into “The Dark Place” or “The Pain Cave”. How can some move past this feat and others can’t? It may be a matter of not moving past, but delaying its arrival. Hopefully we can try and explain this to you.

Commonly the Dark Place is thought to be completely psychological. Mind over matter, right? You may have heard of the Navy SEALs 40% Rule, when you feel as if you are done and can’t go on, you have really only used about 40% of your total exertion. Let’s call this Dark Place, Perceived Exertion. Perceived Exertion is an individual’s perception of total physical strain. It is based on an individual’s perception, differing from one person to another. One of the most popular ways of grading Perceived Exertion is using Borg’s Ratings of Perceived Exertion (RPE) Scale. The lowest rating of the 15 point RPE scale (6) being extremely light and almost no physical strain, whereas the highest rating (20) signifying the activity is extremely difficult and impossible to complete. You can convince yourself the workout is not that bad, or it’s not that tough, however you can’t escape physiology. Perceived exertion is multi-facetted and relies on more than just a psychological component.12440272_1107912505906284_2026491952623907907_o

Borg’s original 15 point RPE was created to coincide with heart rate (HR) (ranging approximately from 60 – 200 bpm). HR has been show to account for about 43% of RPE. Meaning if your HR is 150 bpm and your RPE is 17, about 43% of that is purely based on your elevated HR.

Additionally concentration of lactate in the bloodstream can contribute to RPE. Let’s get super nerdy for a second… When there is a demand for energy utilization, especially during exercise, glucose is broken down and oxidized to form pyruvate, an important part of Krebs Cycle to keep you moving. Lactic Acid is produced as a byproduct of pyruvate. Lactic Acid can be metabolized or removed during exercise, however, when lactic acid is produced faster than the body can process it, lactate concentrations exponentially rise. Everyone has experienced the after effects of Lactic Acid. Soreness, yep, that’s Lactic Acid. Lactate concentration is a main contributor to the feeling of muscles “locking” up during a workout and the general weakness in repeated movements over time. Blood Lactate levels can contribute up to 57% of total Perceived Exertion. Adding up HR and Lactate concentration can strongly predict your Perceived Exertion. Unfortunately you don’t see athletes hooked up to a HR monitor and giving blood samples every minute during a workout, especially in CrossFit.

12888699_1107914572572744_5084838095130981933_oSo, why can’t I go to that Dark Place? More than just the psychological component, physiologically your body is just not adapting to the stimulus as well. As CrossFitters we tend to look at Games athletes as the gold standard, but in reality that’s like a recreational basketball player comparing themselves to Michael Jordan. The work capacity of a Games Athlete is much higher than the average CrossFitter, with that you have all the physiological adaptations that come with it. For an average person doing 100 Double Unders, your HR may spike up to 90% of your max whereas a Games athlete may merely be around 75% or even less. As mentioned before 43% of RPE is based on HR, so just through those 100 Double Unders their RPE should be lower. Now, Lactate concentration. Let’s make a workout of 100 Air Squats. That repetitive motion is going to require energy and thus create lactic acid as a byproduct. A games athlete is going to have the work capacity to complete all 100 air squats unbroken, whereas the average CrossFitter may need to break that up into multiple sets due to fatigue. That fatigue is the increase lactate concentration. Games athlete can remove the lactic acid while performing the task much better than the average person because they have a much higher work capacity. Elevated lactate concentration is going to elevate RPE and will increase the time to complete the task.

11873422_991058057591730_953737812332020300_nHopefully now you can understand that the Dark Place sucks just the same for everyone. Its road leading to it is just a little shorter for some. It doesn’t necessarily mean you are mentally weak, or lack the fortitude to keep going. Physiologically you are demanded to enter the Dark Place sooner, you can push through for a little while but eventually you can’t escape the physical strain. Games athletes appear to enter the Dark Place because you are thinking you are on the same road. In reality everyone has their own path and that Dark Place, some further down their road than others. From an RPE standpoint, let’s look at the brutal 5th workout from the 2014 and 2016 CrossFit Games Open. 21-18-15-12-9-6-3 Thrusters and Burpees. It’s brutal, it’s a ton of work, and generally just sucks. Your RPE is going to be high, likely 17+. For some, 17+ may be on the Round of 15, and you finish in 20 minutes. For others, 17+ may be on the round of 9, and finishing in 14 minutes. Their body just adapted better, lower HR and better lactic acid removal. Psychologically pushing through the “pain” comes into play, but it’s very different when that “pain” comes with 60 total reps left rather than 30.

So how do I get better? How to I lengthen the road to the Dark Place? Well that’s a complicated question and will vary from person to person. The easy answer is working on lowering your working HR. This can be anywhere from working on making your form more efficient to working on aerobic capacity and increasing you maximal oxygen consumption with VO2 training. Additionally work on increasing work capacity, and in turn maximize lactic acid removal. You can do this through increasing general strength, performing repetitions at submaximal weights, and performing tasks when you are already fatigued.



Borg, G. A. (1982). Psychophysical bases of perceived exertion. Medicine & Science in Sports & Exercise, 14(5).

Coutts, A. J., Rampinini, E., Marcora, S. M., Castagna, C., & Impellizzeri, F. M. (2009). Heart rate and blood lactate correlates of perceived exertion during small-sided soccer games. Journal of Science and Medicine in Sport, 12(1), 79-84.

Finch, S. (2015, November 30). The 40% Rule: A Navy SEAL’s Secret to Mental Toughness. Retrieved from http://thehustle.co/40-percent-rule-navy-seal-secret-mental-toughness

Goodwin, M. L., Harris, J. E., Hernandez, A., & Gladden, L. B. (2007). Blood Lactate Measurements and Analysis during Exercise: A Guide for Clinicians. Journal of Diabetes Science and Technology, 1(4), 558-569.

Lactate Profile. (n.d.). Retrieved from http://www.ucdmc.ucdavis.edu/sportsmedicine/resources/lactate_description.html

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