80. SPEED ENDURANCE TRAINING: THE KEY TO BOOST 30 SEC-5 MIN POWER

Photo by Stefan Scheepmaker on Unsplash

In a previous KisW Research Note we saw the physiological underpinnings to be strong on performance of different durations: between ~45 sec and 20 min.

Interestingly we saw that having a high level of capillary density and sodium potassium pump (Na+/K+) is crucial to be strong on efforts lasting between ~45sec and 4min.

Image from Iaia et al. (1)

Why?

Having a high Capillary Density leads to a superior exchange of metabolites between muscle and blood: in particular more hydrogen ions exit faster the cells delaying fatigue, because accumulation of hydrogen ions within the muscle inhibit muscle contraction.

The Sodium-Potassium Pump is a muscle cells membrane transport protein. Its function is to maintain a proper ionic balance (exchanging sodium (Na+) and potassium (K+) ions) across the cell membrane when energy is produced at high rates (read high power output/during high intensity efforts), so that muscle excitability is maintained.

At the moment, which training modality (high volume, high intensity, ….) is the most efficient for inducing capillary adaptations (angiogenesis) is not clear (2). On the other hand, we have some good data which suggest what is the best training strategy to increase the amounts of the Sodium-Potassium Pump. This can be pivotal to understand how to perform at your best in efforts lasting 45~sec-5min.

In this regard, let’s see the study published by Professor Jens Bangsbo and Colleagues (Copenhagen Muscle Research Centre, Denmark) on Journal of Applied Physiology. (3)

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HOW DID THEY TRAIN?