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Effects of training on potassium, calcium and hydrogen ion regulation in skeletal muscle and blood during exercise

conference contribution
posted on 01.01.1996, 00:00 authored by M J McKenna, A R Harmer, Steve FraserSteve Fraser, J L Li
Ionic regulation is critical to muscle excitation, contraction and metabolism, and thus for muscle function during exercise. This review focuses on the effects of training upon K+, Ca2+ and H+ ion regulation in muscle and K+ regulation in blood during exercise. Training enhances K+ regulation in muscle and blood and reduces muscular fatiguability. Endurance, sprint and strength training in humans induce an increased muscle Na+, K+ pump concentration, usually associated with a reduced rise in plasma [K+] during exercise. Although impaired muscle Ca2+ regulation plays a vital role in fatigue, little is known about possible training effects. In rat fast-twitch muscle, overload-induced hypertrophy and endurance training were associated with reduced sarcoplasmic reticulum Ca2+ uptake, consistent with fast-to-slow fibre transition. In human muscle, endurance and strength training had no effect on muscle Ca2+ ATPase concentration. Whilst muscle Ca2+ uptake, release and Ca2+ ATPase activity were depressed by fatigue, no differences were found between strength athletes and untrained individuals. Muscle H+ accumulation may contribute to fatigue during intense exercise and is also modified by sprint training. Sprint training may increase muscle Lac- and work output with exhaustive exercise, but the rise in muscle [H+] is unchanged or attenuated, indicating a reduced rise in muscle [H+] relative to work performed. Muscle buffering capacity can be dissociated from this improved H+ regulatory capacity after training. Thus, training enhances muscle and blood K+ and muscle H+ regulation during exercise, consistent with improved muscular performance and reduced fatiguability; however, little is known about training effects on muscle Ca2+ regulation during contraction.



Ion Transport, Ion Pumps and Muscle Function. International Symposium (1995 : Sandbjerg Estate, Denmark)


1 - 11




Sandbjerg Estate, Denmark

Place of publication

London, Eng.

Start date


End date





This conference paper was published in Acta Physiologica, v.156, n.3, March 1996, pgs.335-346

Publication classification

E1.1 Full written paper - refereed

Copyright notice

1996, Wiley

Title of proceedings

Ion transport, ion pumps and muscle function: an international symposium