Energy system development is seemingly one of the hottest concepts in the fitness industry lately. Regularly, we hear trainers and coaches speak about its importance without delving too much into an explanation regarding the science behind it or its application. Knowing that it’s pretty important, how is it beneficial for athletes, specifically powerlifters?

In order to understand the benefits of energy system development, we must familiarize—or for those possessing exercise science backgrounds, familiarize ourselves again—with each energy system.

Energy systems

This section will serve both as a refresher and a primer, providing coaches and athletes with requisite knowledge to apply to their programming.

Anaerobic energy systems: Two anaerobic energy systems, the phosphagen system and glycolysis, govern activities ranging from maximal intensities (under six seconds) to more moderate intensities (up to three minutes). Within each energy system falls a number of subsystems, which rely on varying contributions from each energy system that also include the aerobic energy system. The interaction of each energy system is predicated upon the intensity and duration of the event or period of exertion.

Aerobic energy system: Also referred to as the oxidative energy system (as it will be called for the remainder of the article), this system supplies the body with energy for activities of lower intensities. However, the contributions of the oxidative energy system begin between 20 and 30 seconds after the onset of exercise (1). This contribution helps with power output, essentially prolonging activity that is regarded as anaerobic in nature such as combat sports or intermediate distance track events.

Adenosine triphosphate: Adenosine triphosphate (ATP) is relied upon for muscular activity and growth. Because the body doesn't have that much ATP stored in it for immediate use, it depends upon each energy system to provide it. Rates at which each energy system produces ATP vary. The phosphagen system produces very little but expends a large amount of it during the course of very intense exercise, which is pertinent for powerlifters because they're either performing limit strength work, nearing or surpassing one rep maximums, or performing a movement at high velocities such as dynamic effort lifts.

Content from the four left columns is found in the Essentials of Strength and Conditioning (1). The column on the far right provides corresponding activities that powerlifters commonly engage in with each energy system used.

Duration of event Intensity of event Primary energy system used Rate/capacity of ATP production Example of event
6 seconds or less Very intense Phosphagen 1 / 5 Lifting at 90% of 1RM of dynamic effort work
6–30 seconds Intense Phosphagen and fast glycolysis 2 / 4 Assistance lifts at 8–12 repetitions per set
30 seconds–2 minutes Heavy Fast glycolysis 3 / 3 Strongman conditioning circuits
2–3 minutes Moderate Fast glycolysis and oxidative energy system 4 / 2 Lower intensity interval training
3 minutes Light Oxidative energy system 5 / 1 Cardiovascular warm up or eating to get a nice bloat going for a meet


Another concept that we see pop up everywhere from textbooks to peer reviewed articles to a strength coach blogging about increasing performance is specificity. In short, specificity refers to the distinct adaptations to the physiological systems that arise from the training program (1). Bodybuilders train for hypertrophy. Distance runners are looking to improve their race pace or cardiovascular endurance. NFL draft prospects who are training for the NFL combine are training to increase their 225-lb bench press repetitions and refining technique necessary to master their 40-yard dash starts, broad jumps, and vertical leaps. Powerlifters aren't any different. They aim to improve their performance in the three events by getting stronger and improving technique on the lifts.

Specificity can be broken down further into movement specificity (read anything by Dave Tate, Eric Cressey, or Mike Robertson to perfect technique on the three lifts) and energy specificity. Because this article relates to energy system development for powerlifters, not improving performance on the lifts, we’ll stick to the script and defer the technique stuff to the aforementioned individuals, who combined boast over a half century years of experience in the trenches.

Energy specificity

Powerlifters looking to optimize their lifting performance should mainly work in sets at six seconds and below. This work can include compensatory acceleration training (CAT) at 50–60 percent of one’s 1RM and plyometrics to develop rate of force development (RFD) (3). It can also include rack squats, dead benches, or deadlifts performed from a deficit or with accommodating resistance such as chains or bands to improve starting strength, speed work within 2–3 reps, or working within 90 percent of a 1RM to improve limit strength. Whichever modality is employed, it will call on the phosphagen energy system if the load is sufficient.

Ideally, powerlifters should work within this energy system for approximately 70 percent of their training session. So if a typical workout is an hour long, approximately 40 minutes should be spent training within the phosphagen energy system. Each set trained within the phosphagen energy system should be interspersed with a period of three minutes of rest. This will permit the lifter to fully recover between each set as the body replenishes its ATP stores (2).

How to improve energy specificity

  1. Get stronger: Improving your maximal strength will permit you to perform a greater amount of work at submaximal loads throughout your training session, thus improving your strength endurance. This will become very helpful as you attempt near maximal or maximal lifts throughout your session.
  2. Don’t forget to develop the other systems too: ATP production is also dependent upon glycolysis and the oxidative energy system. Here’s a refresher from your high school biology class—ATP is secreted by the mitochondria within the cell. Cardiovascular exercise, even at lower intensities, has shown to increase mitochondrial content.  Increased mitochondrial content will improve the process at which ATP is produced. Spend the remaining 30 percent of your training sessions on work that emphasizes a mix of the other systems.
  3. Stay fueled: Proper nutrition and appropriate supplementation will go a long way in helping you improve the efficiency of each energy system.


  1. Baechle TR, Earle RW (2008) Essentials of Strength and Conditioning. 3rd edition. Champaign, IL: Human Kinetics.
  2. Baker JS, McCormick MC, Robergs RA (2010) Interaction among skeletal muscle metabolic energy systems during intense exercise. Journal of Nutrition and Metabolism.
  3. Bumgardner T, Bryant J (2011) CAT, plyo, and board presses. Testosterone Muscle. Available at: http://www.t- cat_plyo_and_board_presses_keys_to_an_explosive_bench.