Energy Systems
Our body has 3 energy systems that are utilised when going through exercise. Each one has their own specialty and depending on your sport or exercise goal, you may want to know a little deeper information on these metabolic systems.
Anaerobic Alactic (ATP-PC)
Firstly, we have the Anaerobic Alactic system which is a powerful but very short energy system. Predominantly used as the first source of fuel during high intensity exercise such as sprinting, jumping, throwing or lifting heavy weights. As the name implies, the Anaerobic Alactic system is supplied without oxygen and requires the ATP-PC stores within our muscles as a fuel source. This energy system supplies for an immediate demand up to 10 seconds as the storage is quite small. As the system fuels intense short bouts, it is quite a powerful source which we train to increase our power output for many power demanding sports such as Powerlifting, Olympic Weightlifting, Wrestling, Sprinting etc. Due to the explicit nature of how intense the demand is, the energy system requires a significant recovery time for it to be used again. Recovery time of the energy system varies from 2-3 minutes for ATP-PC stores to recuperate. When training the Anaerobic Alactic system, we need to consider the high demands of the system and the ability to replenish ATP-PC stores within the muscle so that we are able to repeat high intensity exercise more often. Training the Anaerobic Alactic can help improve our ability to lift heavy weights more often or sprint more often which is crucial for improving overall work capacity with high intensity exercise.
Anaerobic Lactic (Glycolysis)
Secondly we have the Anaerobic Lactic energy system. The Anaerobic Lactic system uses blood glucose and muscle glycogen as a fuel source to fuel moderate intensity exercise. As the Anaerobic Alactic system depletes, the Anaerobic Lactic system will continue to supply energy to whichever activity for up to 1-2 minutes until it is depleted. This energy system is used in conjunction with the Anaerobic Lactic system as they all correlate together at the same time. The Anaerobic Lactic system relies heavily on the fuel source from our muscles which we require from carbohydrates (broken down into either glucose or glycogen). During this time, lactic acid accumulates within the blood and muscles which causes a burning sensation through exercise. Exercises such as lifting moderate weight or 400m sprints rely heavily on the Anaerobic Lactic system. Improving our Anaerobic Lactic system helps to buffer lactic acid and maintain moderate intensity exercise often and longer so that we are able to perform at a higher output. This could mean running longer and faster on the field for Rugby or out lasting your opponent in a really long scramble in BJJ.
Aerobic System (Oxidative)
Lastly we have the Aerobic System which is the longest lasting energy system. It uses oxygen to fuel our body through lower intensity exercise and can last for a very long duration. Predominantly taking over after 2-3 minutes of exercise, it is used for long duration but continuous efforts such as long distance running. The Aerobic System breaks down fatty acids with oxidative processes which fuel the body for long duration exercise. It should be noted that training the Aerobic System helps to increase the size of the mitochondria in our cells which can make us more efficient at using oxygen as fuel. Training the Aerobic System builds up overall work capacity, aerobic fitness and improves general health qualities to reduce the chance of cardiovascular disease or obesity. The fitter an individual is, the less rest they would require between training sessions. They would also be able to handle more work during an individual training session which could increase overall training volume and stimuli for the body to progress.
Time Zones To Train Each System
Ideally when trying to improve each energy system to improve our sport, we need to identify which system should be prioritised and when. All energy systems will be used during all exercise however the percentile of fuel from each system will vary depending on the duration and intensity of the exercise. The duration of the task and the rest periods are crucial for buffering and conditioning our bodies to replenish the fuel sources for the task.
For Anaerobic Alactic:
1-2 times per week
5-10s intervals
8-18 repetitions
20s - 5min rest in between
Example: 8 rounds of 10s on (100% intensity) followed by 20s rest
For Anaerobic Lactic:
1-3 times per week
20s - 2 min intervals
4-12 repetitions
60s - 8min rest in between
Example: 6 rounds of 1 min on (85-90% intensity) followed by 1 min rest
For Aerobic:
3-5 times per week
15min+ Intervals
Usually just 1 interval
No rest
Example: 40min jog at 55% intensity
These are just examples and depending on what season you’re in, your fitness levels and the sport you participate in, the times will vary to match the specificity of those variables. I hope this article helps you guys understand a little more on energy systems and how they can help your training!
Peace out Movement Fam!
Coach Matty!