Research

Energy balance

Sprint training (ST) specifically elevates creatine kinase (CK) activity, whereas speed endurance training (SET) does not, suggesting that the rate of creatine phosphate (CP) utilization, rather than total CP depletion, drives CK adaptation.

If you want to increase your muscle's creatine kinase activity, focus on very short, maximal sprints (e.g., 6-second all-out efforts). Speed endurance intervals, while beneficial for other adaptations, do not appear to stimulate CK increases in the same way.

GoodSupportsHIGH confidence
In SET, muscle CK was not changed, whereas in ST, it was higher (P < 0.05) after, compared with before, the training period... it may be that it is a high rate of CP utilization rather than the total net utilization of CP that is important for the adaptation of CK to training.
Magni Mohr et al. · American Journal of Physiology-Regulatory, Integrative and Comparative Physiology · 2006

Why this rating

Clear biochemical measurement with statistical significance.

Source

Effect of two different intense training regimens on skeletal muscle ion transport proteins and fatigue development

Magni Mohr et al. · American Journal of Physiology-Regulatory, Integrative and Comparative Physiology · 2006

DOI 10.1152/ajpregu.00251.2006

rct · n=13Cited 226×
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DOI resolved against Crossref · corpus check 2026-06-10

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