by Evan Peikon
Before Reading this Article you may want to check out the following articles for a base understanding:
Energy Systems: N=1 …. Period! !
ATP-CP Battery: Why Absolute Strength isn’t Everything In the Sport of Fitness
In the sport of fitness everyone acknowledges that without sufficient strength, you will get nowhere. This fact isn’t even debatable at this point in time. However, most competitors fail to acknowledge is that a well developed aerobic system (Aerobic base) is just as important as a strength base, if not more important. For some reason having a well developed aerobic system has become taboo in the crossfit community, and training to develop the aerobic system sufficiently seems to go against the commune. What fitness athletes fail to realize though is that the aerobic system plays a huge role in their ability to recover from training, as well as their longevity in the sport. Not to mention the fact that The Sport of Fitness is dominated by athletes with highly developed Aerobic Power systems. Aside from helping improve recovery, the aerobic system also affects multitudes of other limiting factors in achieving optimal performance which will be discussed in full detail in this article.
To Start, a well developed Aerobic System Decreases Heart Rate:
This one is pretty common knowledge, but having a well developed aerobic system will strengthen the cardiac muscle to improve the pumping efficiency of the heart. Meaning that at any given relative intensity, one’s heart will do less work to pump enough oxygenated blood to their working muscles.
Decrease Lactate Usage (& make better use of lactate as fuel):
When doing high intensity exercise muscles begin to produce lactate. Common to contrary belief lactate (synonymous with lactic acid) does not cause muscle fatigue, and can even be used as a fuel source. However, lactate must first undergo processing. If one has a powerful aerobic system one’s body will shuttle lactate into the Brooks Cycle (aka lactate shuttle). Meaning that the lactate will be converted into Pyruvate which then enters the Krebs Cycle and is converted into ATP by the aerobic system. The body can then redistribute it to the working muscles under duress, or use the lactate in combination with oxygen as fuel. However, those without a well developed aerobic system may go through a less efficient process to turn lactate into fuel called the Cori Cycle. In the Cori Cycle lactate is turned to pyruvate. Pyruvate would then undergo gluconeogenesis which means it would be converted into glucose to be used by the muscles. One must also keep in mind that when lactate is produced a positively charged Hydrogen (H+) ion is released which can potentially alter the Ph in a muscle. The H+ is quickly buffered in the blood though and converted into carbon dioxide which is sent to the lungs and exhaled (in order to maintain acid base balance). While this fact isn’t necessary to know, it is relevant to this process. (Also take into account this is a highly simplified version of what happens, but for the sake of coherence I left out a few sub steps. If you’d like to know the rest of the scientific details you can post your questions to the comments section and I’ll answer them there).
Application in Sport:
If you don’t have a well developed aerobic system you may accumulate excess lactate in the muscle due to the fact that you cannot efficiently shuttle it via the Brooks Cycle and use it as fuel. What this means is that you will be forced to take breaks when you shouldn’t, and those breaks will be way longer than they would be if you had a well developed aerobic system. Because of this you will have to work a lot harder to sustain a pace that other competitors find manageable (this even applies to higher intensity, or anaerobic based, pieces where the oxidative system is not the energy system predominantly in use).
Restore ATP-CP Quicker:
I’ve already written an entire article on the ATP-CP Battery which you can find here…. ATP-CP Battery: Why Absolute Strength Isn’t Everything In the Sport of Fitness. So to keep this section concise, I’ll discuss this in more general terms. When using the aerobic system (or oxidative system) you generate ATP via aerobic metabolism. Which is very efficient. Aerobic metabolism generate 38 moles of ATP per 1 mole of Glycogen, which will allow one to quickly recharge their CP battery (without discussing how many moles of ATP other systems resynthesize, just know that 38 is a lot). As I’ve discussed in the CP-Battery article, this is also why many athletes who have an endurance background have very “good” CP batteries relative to other athletes.
Decrease Time for EPOC to Reach Baseline:
After high intensity exercise oxygen is needed to restore your bodily systems to homeostasis. Not only do your bodies fuel sources need to be replenished, but your body must also balance its hormones, repair cells, and shift back into an anabolic state. However, the issue is that after the intense exersice your body goes into what is known as “Oxygen Debt”. Which is formally known as EPOC (Excess post-exercise oxygen consumption). Meaning that you need to pay the “debt” to fully recover (also keep in mind that the larger the EPOC, the longer it takes to pay back). Some factors that contribute to the EPOC include replenishing ATP-CP, converting lactate to pyruvate, and resynthesizing glycogen. This period of recovery also helped your body brings its temperature back to baseline, and bring the bodies heart rate to a resting level (hemoglobin is also reoxygenated in the blood at this time). At this point you may be wondering why this is important… Well, the higher one’s aerobic capacity is, the less time it will take to bring the body back to baseline and pay off the “oxygen debt”.
Application in Sport
During any Fitness competition one is forced to do multiple events/ workouts in a day. If one doesn’t have the requisite aerobic base they will not bring their body back to baseline between events and will continue to breakdown as the day goes on. On the other hand, the athlete with a large aerobic base will be able to completely pay their debts between events and will be better situated to perform at their peak potential. This idea can also be depicted in a Crossfit Games type scenario where athletes are performing multiple workout a day for up to five days straight. Many athletes come out strong, but by the 3rd-4th day of the games they start to fade off. On the other hand, there are numerous competitors who just place okay in the first few days, only to be fully recovered as the week goes on and finish the competition in a top spot. Obviously many factors go into that besides a large aerobic capacity, but you can guarantee those who sustain their intensity over the course of the competition have the aerobic base to support their efforts.
While out of the scope of this article it is important to note that:
-Building an aerobic base will also increase oxidative enzymes in the muscles (as well as glycogen/ triglyceride stores in the muscles).
-Without the requisite aerobic base an athlete regularly performing high intensity activities hormones will be out of whack (article to come on this soon), which will significantly hamper any progress they plan on making.
Just like in strength training, building an aerobic base requires well thought out programming. You would never just pick random weights up and do whatever set/ rep scheme comes to mind at that very moment. So why do athletes just go run a random time/ distance or do a long metcon every other week and expect their aerobic capacity to significantly improve? It only makes sense that you would need a well programmed progression to build your aerobic capacity without losing strength or affecting your recovery.
If your interested in receiving programming aimed at improving your aerobic capacity or any other weaknesses you may have check out our exclusive coaching page or our free crossfit competitors program blog