The glycolytic energy system (GES) plays a significant role in high-intensity activities requiring short power bursts. Whether you’re an athlete or a fitness enthusiast, understanding the GES will help you to get the most out of your training.
The GES drives short bursts of explosive power
The glycolytic system relies mainly on glucose and does not require oxygen. It is primarily active during high-intensity, short-duration activities like sprinting or weightlifting. This system produces energy more quickly than the oxidative system.
Training at “strong” to “very strong” intensity can develop the glycolytic system. An effort that is about 5-7 on a 1-10 scale would put you in the zone of this energy system. *
Lactate fuels the drive and sets the boundaries
Lactate was once considered a waste product causing fatigue and muscle soreness. We now understand that muscles can use lactate to produce adenosine triphosphate (ATP) through a process called anaerobic glycolysis.
We use the oxidative energy system when blood lactate is below 2 mmol/L. As the activity intensity increases and blood lactate rises above 2 mmol/L, the body begins to rely on the GES. This is the “aerobic threshold” or lactate threshold 1 (LT1).
As the activity intensity increases and blood lactate rises above 4 mmol/L, the muscles produce more lactate than can be cleared. This is the “anaerobic threshold” or lactate threshold 2 (LT2).
Advantages of training the GES
Training in the GES improves performance by increasing your lactate threshold, allowing you to sustain a higher intensity for longer before fatigue sets in.
Moreover, it improves performance by enhancing the body’s ability to generate energy quickly and efficiently. This increased power and speed can improve performance in training, sport, and many real-world activities.
Effective training strategies for the GES
High-intensity Interval Training (HIIT): HIIT involves alternating periods of high-intensity exercise with short recovery periods.
For example, sprinting for 20-30 seconds, followed by a brief 10-20 second rest period, can be a highly effective HIIT workout. Incorporating exercises like burpees, squats, and kettlebell swings can also be effective while adding variety.
Circuit training: Circuit training combines a series of exercises performed quickly with minimal rest between exercises.
For example, completing as many rounds as possible in twenty minutes of 5 pull-ups, 10 push-ups, and 15 squats will not only target all the major muscle groups but will keep the intensity elevated.
Sport-specific drills: Athletes who require short bursts of intense effort can benefit from sport-specific drills. Soccer players can practice shuttle runs, basketball players can focus on high-intensity dribbling and shooting drills, and martial artists can engage in quick and explosive striking or grappling movements.
Fartlek training: Fartlek training (FT) combines continuous aerobic exercise with bursts of high-intensity effort. Alternating steady-state and sprinting efforts can promote overall aerobic fitness while challenging the GES.
Glycolytic training at CrossFit Missoula
In the CrossFit Missoula program, four of the six days of programming will be Metcons (metabolic conditioning). Our metcons are almost always either HIIT or circuits in design.
MetCons are 10-25 minutes and often blend elements of gymnastics (body weight exercises), weightlifting, and “cardio” (e.g., running, rowing, jump rope).
If you recall from the Strength Training email, one of our training days is the “heavy day.” Our sixth day, Saturday, is an open gym. Members make up a missed workout or design their own.
In next week’s email, we will consider the Oxidative energy system (OES) and its benefits to health and performance. Training in the OES goes by many aliases — Zone 2, base training, aerobic conditioning, and long slow distance (LSD).
* Dantas, José L., et al. “Determination of Blood Lactate Training Zone Boundaries With Rating of Perceived Exertion in Runners.” Journal of Strength and Conditioning Research, vol. 29, no. 2, Feb. 2015, pp. 315–20.
Go to next article in the series
Building the base – The oxidative energy system