Metabolic conditioning for work capacity
The breakdown of glucose to usable energy has two pathways, with the second being an extension of the first.
The first component of the pathway is the breakdown of glucose to energy that can be used to fuel movement, which occurs quickly and without the presence of oxygen (anaerobic glycolysis).
However, this comes with the by-product of pyruvate, which becomes lactic acid - ie. the burn - if there is no oxygen available to further metabolise it.
This energy system provides a large amount of energy over relatively short periods of time, mostly 30-seconds to two minutes.
But the energy capacity is essentially limited by the accumulation of lactic acid, which aside from causing localised muscular discomfort, increases the acidity within the muscle and interferes with both muscular contraction and energy production.
As people become more experienced with metabolic conditioning training, their muscles become better at clearing lactic acid from the muscle (called ‘shuttling’) which slows the increased acidity of the muscle.
This training also rapidly increases the heart rate and challenges the cardiovascular system, leading to adaptations in the heart and lungs to handle the increased work capacity.
Metabolic training is an important component of any training program, for both the muscles and cardiovascular system.
Pure metabolic conditioning that my clients are familiar with includes bike sprints, sled pushing, weighted carries and rowing intervals.
Resistance training and metabolic conditioning also begin to merge when we begin to pair multiple exercises together with little to no rest in between.
In the gym, metabolic conditioning is typically done after the resistance training component of a session.
Rowing intervals or bike sprints can also be used at the end of the session as a ‘finisher’, but it’s important to note that the performance will be impacted by the 50-minutes of training completed beforehand.
So if someone wants to get better at 500m rowing or the like, it should be done earlier in the session (ie. immediately after the resistance training work) to ensure optimal performance.