This article is Part 2 of a 3 part series that outlines the three basic energy systems used in sport, their interactions with one another, and how to train each one.
Below the Introduction (technical explanation), we offer 7 sessions (in 3 stages) for training the Glycolytic System.
Glycolysis literally means the breakdown (lysis) of glucose and consists of a series of enzymatic reactions. The carbohydrates we eat supply the body with glucose, which can be stored as glycogen in the muscles or liver for later use.
The end product of glycolysis is pyruvic acid. Pyruvic acid can then be either funneled through a process called the Krebs cycle (see the Oxidative System in next weeks article) or converted into lactic acid (lactate + hydrogen ion). Traditionally, if the final product was lactic acid, the process was labelled anaerobic glycolysis and if the final product remained as pyruvate the process was labelled aerobic glycolysis.
Oxygen availability only determines the fate of the end product and is not required for the actual process of glycolysis itself. Oxygen availability has been shown to have little to do with which of the two end products, lactate or pyruvate is produced. This is where the terms aerobic meaning with oxygen and anaerobic meaning without oxygen become a bit misleading (5).
Alternative terms that are often used are fast glycolysis if the final product is lactic acid and slow glycolysis for the process that leads to pyruvate being funneled through the Krebs cycle. As its name would suggest the fast glycolytic system can produce energy at a greater rate than slow glycolysis- it has greater power. However, because the end product of fast glycolysis is lactic acid, it can quickly accumulate and is thought to lead to muscular fatigue (1). The contribution of the fast glycolytic system increases rapidly after the initial 10 seconds of exercise. This also coincides with a drop in maximal power output as the immediately available phosphogens, ATP and especially PCr begin to run out. By about 30 seconds of sustained activity the majority of energy comes from fast glycolysis (2). At 45 seconds of sustained activity there is a second decline in power output (the first decline being after about 10 seconds). Activity beyond this point corresponds with a growing reliance on the oxidative energy system.
Training which emphasises the glycolytic energy system results in increased muscular glycolytic enzyme activity- most notably increases in concentration of lactate dehydrogenase, phosphofructokinase and glycogen phosphorylase. (7). This type of training which creates high levels of intramuscular levels of lactate and pyruvate (monocarboxylates) has also been shown to increase the concentration of monocarboxylate transporters in the muscle. These transporters act as revolving doors in the muscle which improves the rate of removal of these products. Improving the function of the glycolytic system will shift an individual’s on-set of blood lactate accumulation curve to the right, meaning the player is able to work at a greater exercise intensity for a given blood lactate concentration.
Training to emphasise this system should include near maximal efforts with work:rest of 1:3-7. Sessions should be designed to ensure different lengths of effort and work:rest are programmed so players are exposed to different levels of lactate production.
Training the Glycolytic System – Session examples
100m efforts– 2 blocks of 10 X 100m efforts starting each new effort on 60s
Aim to complete each effort in under 16s
Alternate between 100m straight through, 2 X 50m and 5 X 20m
2-minutes recovery between blocks
Down & up efforts– Starting on stomach, up run forward 5m, down flat to stomach, up as quickly as possible running backwards 5m
Continue for 20s- focus on maintaining speed of movement throughout work period
Begin next effort on 60s
Complete 2 blocks of 10 efforts
Shuttle- Sprint to 22m mark- drop to stomach then up & run backwards to 10m marker
Drop to stomach then up & sprint through to 50m mark
Easy jog through to far end- get through in 20s
Begin each new effort on 80s
Complete 2 blocks of 5 shuttles
10s work:20s recovery- Calculate a player’s 85% of maximum speed (e.g.: if 10m/s then will be 8.5 m/s)
Multiply by 10 then set a marker at this distance
Player aims to cover this distance in 10s with a 20s recovery period
Complete 4-6 efforts each block (emphasis should be quality of effort)
Complete 2-3 blocks with 2-minutes recovery between blocks
Wrestle- Turtle flips- 1 player is on the ground on all 4s while a partner stands next to him/her
The player on all 4s tries to stay on all 4s while the partner tries to flip the player onto their back
If they are flipped the player on all 4s re-sets and the drill continues for the time
15s work period starting each new effort on 60s
Complete 5 efforts in each role
2-minutes recovery then repeat
200/300/400m efforts- Vary between straight line and shuttle
Focus on maintenance of intensity throughout session- identify specific speed bracket you want the athlete to maintain (eg:6.5-7.0m/s)
Example- 2 X 200m completed in <30s beginning new effort on 2-minutes- 1:3 work:rest 2-minutes recovery 2 X 300m completed in <45s beginning new effort on 2:30- approx. 1:3 work:rest 2-minutes recovery 2 X 400m completed in <1:05 beginning new effort on 5-minutes- approx. 1:5 work:rest
Repeat chase, catch & wrestle drill- In a restricted area (10m X 10m) 1 athlete is the chaser while the other is the evader
Working on 45s intervals- the evader tries to stay away from the chaser
When the chaser catches the evader he/she wraps them up then wrestles the ball from them
The evader makes this ball wrestle as difficult as possible
As soon as the ball is stolen it is thrown back to the evader who again tries to evade the chaser
This continues for the work period- emphasis is on high intensity in the chase/evasion and then the competition for the ball
Complete 5 X 45s work intervals with each new effort beginning on 2:15- 1:2 work:rest
2-minute recovery between blocks
Repeat with the roles changing
1. Baechle TR and Earle RW. Essentials of Strength Training and Conditioning: 2nd Edition. Champaign, IL: Human Kinetics. 2000.
2. McArdle WD, Katch FI and Katch VL. Essentials of Exercise Physiology: 2nd Edition Philadelphia, PA: Lippincott Williams & Wilkins. 2000.
3. Noakes TD. Physiological models to understand exercise fatigue and the adaptations that predict or enhance athletic performance. Scandinavian Journal of Medicine and Science in Sports. 10, 123-145. 2000.
4. Stager JM and Tanner DA. Swimming: 2nd Edition; An International Olympic Committee Publication. Oxford UK: Blackwell Scinece Ltd. 2005.
5. Wilmore JH and Costill DL. Physiology of Sport and Exercise: 3rd Edition. Champaign, IL: Human Kinetics. 2005.
6. Gastin PB. Energy system interaction and relative contribution during maximal exercise. Sports Med Journal. (31) 10, 725-741. 2001.
7. Ross A and Leveritt M. Long-term metabolic and skeletal muscle adaptations to short-sprint training: Implications for sprint training and tapering. Sports Med Journal. (31) 15, 1063-1082. 2001.
This is Part 2 of a 3 Part Series. Click here for Part 1 and 3.
Click here to see David Boyle’s Rugby Union Training Programs.
Click here to see John Mitchell’s Basketball Training Programs.
Cameron is the Director of Pro Training Programs