With as much attention anaerobic energy system training has gotten in the literature and even more so by coaches, it’s important we don’t forget the aerobic energy systems. All too often I see this important form of training fall by the wayside, despite a veritable avalanche of evidence suggesting the importance of aerobic energy training.


Now, maybe you train in a sport like MMA and you’ve decided already that this is incorrect. With 5 minute rounds of stop-and-go action, anaerobic training must be the more important method. Think again. A landmark study in Sports Medicine pointed us to a very different answer. The aerobic energy systems contribute half of your energy output at somewhere between the 1-2 minute marks, or generally about 75 seconds if you are going all out. That means most of your energy, especially if you are well-trained, may well come from aerobic pathways, even if you aren't what we normally think of as an endurance athlete.


As a result, it's important to determine the intensity you can maintain with a primarily aerobic contribution. How to do it is a different matter. In the lab, scientists use blood samples, ventilation masks, and so forth, but most of us don’t have access to that sort of equipment. However, a study this month in the Journal of Strength and Conditioning covered the topic of critical velocity, an important performance marker. In the study, scientists wanted to learn if critical velocity was useful as a measurement for those of us who don't train in clinical settings.

Breaking Muscle Shop


Critical velocity is a fancy way of saying “the highest intensity that you could theoretically maintain indefinitely.” The scientists used swimmers to verify if we could use critical velocity tests to determine aerobic ability. Sure enough, the researchers discovered that testing for critical velocity is a great way to determine maximum lactate at each pace, as well as lactate threshold and other important markers for aerobic fitness. You don't need any fancy equipment, other than a way to measure pace. You simply pick various paces and test the time to exhaustion. The highest intensity you can maintain is your critical velocity. When this increases due to training, your aerobic fitness has improved. Pretty cool stuff.


Now, the researchers were only concerned about critical velocity as a test for aerobic fitness, but I like big picture thinking and see a greater importance for this test. Setting a pace is the key to winning every athletic event out there, and you can’t do that if you’re not fit enough. So you need to use critical velocity testing to help you master your pace.


To use critical velocity testing to maximize performance, find your critical velocity in the sport you compete in. Once you’ve done that, determine if that’s the pace you wish to set - in other words, the pace that will help you win. If not, you have work to do, so get to it.



1. Paul Gaston, et. al., “Energy System Interaction and Relative Contribution During Maximal Exercise,” Sports Medicine, 31(10), 2001.

2. Argyrus Toubekis, et. al., “Metabolic Responses at Various Intensities Relative to Critical Swimming Velocity,” Journal of Strength and Conditioning Research, 27(6), 2013.


Photo courtesy of Shutterstock.