Boxing - Energy Systems Breakdown

Conditioning is key when it comes to boxing, you cannot underestimate this important element. You can have a hard punch but if you cannot last the rounds, you're in trouble!

“He can have heart, he can hit harder and he can be stronger, but there’s no fighter smarter than me.”

— —Floyd Mayweather Jr.

Why it's important

Boxing requires a mix of all the different variables that come with the human body. It includes a mix of strength, endurance, power, speed, agility, skill and you need to work the different energy systems within the body.

A note on energy systems

The human body is powered by three energy systems...

Two of these energy systems are described as anaerobic, or non-oxidative. Energy is produced from other sources other than oxygen. The two anaerobic energy systems are the ATP-PC system and the glycolytic system. The third energy system is the aerobic, meaning that oxygen is used for the oxidation of glycogen to produce energy.


There are two main parts of the anaerobic system: the lactic and alactic. We often equate lactic acid to the burning feeling in our muscles when we work extremely hard. Through experience, we know that it takes some time before we feel this. Research says that the release of lactate begins at about 0:15 - 0:20 of high intensity work. So the alactic system is providing the energy from 0:0 - 0:15/0:20 of all-out effort. We breakdown the alactic and lactic systems even further into power training and capacity training. Power refers to the early stages of the system and capacity to the later stages


ATP-PC System

The ATP-PC fuels short yet highly intense activities such as 100m sprint. The total capacity of this system is 10-30 seconds.

ATP ( Adenosine triphosphate ) is the energy molecules of the cells, synthesised mainly in mitrochondria and chloroplasts. The ATP-PC system relies on ATP already present in the muscles and on a limited amount of phosphocreatine (PC) to regenerate ATP. Based on limited stores within the muscles, this energy system quickly runs out of gas.

Clearly the duration and intensity of exercises are inversely related. High intensity work can only occur in short bursts, followed by rest intervals to promote recuperation. PC reformation requires ATP and occurs only during a period of recovery.


Consider a fighter that throws a rapid 3-punch combination ( energy production ). Following the combination he then circles the ring ( recovery ) before engaging his opponent again. The fighter cannot sustain a continuous barrage of barrage throughout the round. Speed and power will gradually decline, hence the importance of a proper conditioning program.

Glycolytic System

This energy system derives energy from glycogen. Glycogen ( stored carbohydrates ) is stored in the muscles and the liver and undergoes what is called glycolysis. Glycolysis involves a sequence of reactions that converts glucose in pyruvate and ATP.

Lactic acid is also produced when oxygen demands surpass oxygen supply. The increase in lactic acid brings about an increase in the production of hydrogen ions. The increased presence of hydrogen ions creates a more acidic environment in the muscles. Such an environment slows down enzyme activity and will eventually halt muscle action. The capacity of this system is approximately 90-120 seconds.

As the ATP-PC system is depleted, the glycolytic system becomes more and more important in generating energy to sustain the intense activity ( ex. sparring for a 3 minute round )

Aerobic Energy System

This energy system uses proteins, fats and carbohydrates to produce ATP for energy. As intensity increases, the aerobic system becomes more reliant on glycogen ( carbohydrates ) as the primary energy source. If intensity continues to increase, the two non-oxidative ( anaerobic ) energy systems must furnish the energy required for the activity.

The aerobic energy system can sustain exercise for lengthy periods of time ( marathon running, running distances )


This is the system that transports oxygen through the body and to working muscles. Aerobic training strengthens the heart and increases stroke volume, the amount of blood pumped out each heartbeat. The larger the stroke volume, the more oxygen gets delivered in a shorter time. For boxers the aerobic system is used largely for recovery. Think of a boxer between rounds, the fighter getting more oxygen delivered more quickly will recover better; this is critical in the later rounds. The same is true during camp, only on a larger scale. The quicker the fighter recovers from session one, the better they will be in session two and so on. Again, this is very important for the later portion of camp. When training for aerobic conditioning, it is most beneficial to use long durations where the heart rate remains elevated but not too high. This is highly individual, but a safe bet is below 150 beats per minute. Above that rate, the fighter begins producing lactic acid. This is known as the anaerobic threshold.


As you can see it is important for you to train all 3 energy systems as this is what boxing requires. During a fight your body is using all 3 at all different times of the round. This is why a proper conditioning plan is so important. You cannot just have a hard punch if you come up against a better conditioned boxer as they will use that to their advantage ( unless they get knocked out early )

In the next article we will be breaking down why aerobic conditioning is important ( roadwork  and how to increase your anaerobic capacity ( work capacity )

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