Fitness training plays an important role in your movement practice. It involves workouts targeting specific energy systems in order to achieve the intended results.
The human body has three distinct energy systems — oxidative, glycolytic, and phosphagen. These energy systems use a variety of fuels, such as carbohydrates, fats, and proteins, to produce energy for working muscles.
All three systems contribute to energy production. But their relative contributions vary depending on the intensity and duration of the activity.
The oxidative system
The oxidative system uses fats, glucose, amino acids, and oxygen. It is primarily active during low-intensity, long-duration activities. This system is efficient in producing energy but requires oxygen to function effectively.
Training at “moderate” intensity can develop the oxidative system. Moderate intensity requires an effort that is a 4 on a 1-10 scale. We often refer to this as “aerobic”, “Zone 2” or “base” training.
Heart rate and blood lactate are also useful guides for training intensity. The upper limit of the oxidative pathway is usually around 70-80% of your maximum heart rate and 2 mmol/L of blood lactate. If you cross this threshold, your body will begin using the glycolytic energy system.
The glycolytic system
The glycolytic system relies mainly on glucose and does not require oxygen. It is primarily active during high-intensity, short-duration activities, such as 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 a 7 on a 1-10 would optimally challenge this energy system.
The top range of the glycolytic system is usually around 80-90% of your max heart rate and 4 mmol/L of blood lactate. If you cross this threshold, your body will begin using the phosphagen system.
The phosphagen system
The phosphagen system uses creatine phosphate as fuel. Primarily used for explosive movements requiring quick bursts of energy. The phosphagen system provides immediate energy but has limited capacity.
Activities that develop the phosphagen system include sprinting, power lifting, and Olympic weightlifting.
In summary, a well-rounded training program will include workouts that target and develop each energy system.
Now that we know what we need to do, the next question is how do we do it?
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Strength training: “heavy days” for body and mind