Energy System Conditioning

Energy System Conditioning

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Prepared by: Michael Speranza, Strength and Conditioning Coach, Australian Institute of Sport
Evaluated by: Ross Smith, Manager Strength and Conditioning Operations, Australian Institute of Sport
Last Updated: October 2016

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There are three main energy systems that influence how ATP is stored, used and replenished; alactic energy system, lactic energy system and the aerobic energy system. [1] When undertaking energy system training it is important to understand how training variables influence the extent of the energy system being used. It is essential to understand that the energy systems do not work in isolation. All three systems operate together but the one system that dominates is dictated by the intensity, activity duration, the activity situation and movement efficiency of the activity.[2]  Table 1 gives an example of the energy demands of some sporting events.[3]

Table 1. Energy system demands for sporting events. 

Relative contribution of each energy system
100m Freestyle swim
800m Track
10km Run

Through the manipulation of training variables these energy systems can be targeted through a specific training program.[1] These variables include:

  • Type – Is the activity intermittent or continuous?
  • Duration – Refers to the length or distance of repetitions, rest and / or activity in its entirety 
  • Volume – This variable includes the number of repetitions, sets, and / or total distance)
  • Intensity – Describes the effort of the activity. There are numerous way to quantify intensity, including (but not limited to), kilometres per hour, strokes per minute, percentage of maximal heart rate 

Alactic Energy System

The alactic energy system constitutes the initial component of the anaerobic system providing the majority of energy contributions for efforts up to 10 to15 seconds. Training to improve the capacity of this quality requires an individual to complete maximal work effort with relatively long recovery periods.[2] This energy system is synonymous with the development of speed and agility (link to speed development clearinghouse page).The guidelines for alactic training sessions are shown in table 2.

Table 2. Alactic Energy System Training Guidelines 

Rep Duration
No. Reps
5-15 seconds
3 - 8
2 - 3

The following is an example of an alactic energy system training session:

Maximal 40 metres sprints
2 sets of 5 x 40m sprints efforts starting from various body positions. The individual will work back to the start position and commence their next effort on the minute (approximate work: rest ratio = 1:10).
2-3 minutes rest between sets.

Latic Energy System

This system constitutes the latter component of the anaerobic system producing the predominant energy contributions for efforts up to 40 to 60s. Training to emphasise this system should include near maximal efforts with a work: rest ration of 1:3-6. As the title suggests, this energy system creates high levels of debilitating intramuscular lactate. Improving the function of this energy system allows individuals to work with greater efficiency for a given blood lactate concentration.[2] Sessions can be manipulated by different durations and work: rest ratios to expose individuals to different levels of lactate production. The guidelines for lactic training sessions are shown below in table 3.

Table 3. Lactic Energy System Training Guidelines 

Rep Duration
No. Reps
90 - 100%
15-45 seconds
3 - 8
2 - 3
1:7 - 6

The following is an example of a lactic energy system training session:

45 second Rower Ergometer efforts
2 sets of 5 x 45 second efforts.
The aim is to complete a minimum of 180 metres every rep.
3 minutes rest between reps (work: rest ratio of 1:4)
5 minutes rest between sets.

Aerobic Energy System 

The aerobic or oxidative system provides the predominant energy contribution for efforts that last longer than 45 seconds, or for repeated efforts of shorter durations. Emphasis on this energy system will be seen in an increase in an individuals’ aerobic performance, the maximal amount of oxygen the body can take and utilise.[1] The aerobic energy system can be trained through continuous or steady state activity at a sub maximal effort (65-80% intensity) i.e. >20minute road run or cycle. Alternatively, the aerobic energy system can be interval based training. The guidelines aerobic training sessions are outlined in table 4.

Table 4. Aerobic Energy System Training Guidelines

Rep Duration
No. Reps
15+ seconds
3 - 20
2 - 3
1:0.5 - 2

The following is an example of an interval based aerobic energy system training session:

100m Running Efforts
2 sets of 10 x 100m runs
The aim is complete each effort in 20 seconds.
20 seconds rest between reps (work: rest 1:1).
2-3 minute rest between sets.

As stated earlier energy systems do not work independently, therefore it is essential that athletes develop all components of fitness, not just the predominant energy system. For example, football players require high levels of aerobic fitness but it is also essential for the anaerobic energy systems to be highly developed for explosive running demands and high intensity repeat efforts. These energy systems may be trained independently with separate sessions for each energy system. Alternatively, all of the energy systems can be developed in one combined session. How energy system training is structured will depend on multiple factors including, requirements of the sport, level of athlete and time available.

Further Resources and Reading 


  1. Baechle, T.R. and R.W. Earle, Essentials of strength training and conditioning. 2nd ed. (2000), Champaign, IL: Human Kinetics.
  2. Mitchell, J., et al., Energy system training, in Strength and Conditioning: Long term player development curriculum. (2012).
  3. Foss, M.L., A. Fox, and S.J. Keteyian, Fox's Physiological Basis. 1998: McGraw-Hill Higher Education.


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