Faculty Collaboration Database

Lactate and contractile force in frog muscle during development of fatigue and recovery. Am J Physiol 1976 Aug;231(2):430-3

Date

08/01/1976

Pubmed ID

1085570

DOI

10.1152/ajplegacy.1976.231.2.430

Scopus ID

2-s2.0-0017201393 (requires institutional sign-in at Scopus site)   95 Citations

Abstract

The relationship between lactic acid concentration and twitch tension was reevaluated in electrically stimulated frog sartorius muscle. In muscles stimulated under anaerobic conditions at a rate of 30 stimuli/MIN CONTRACTILE FORCE DECREASED TO 36% OF THE INITIAL VALUE IN 15 MIN, Concomitantly lactate increased from 3.3 to 18.7 mumol/g of muscle. The correlaiton between the increase in lactate and the decrease in contractile force was significant (r = -0.99, P less than 0.000001). Recovery occurred in two phases. A rapid increase in contractile force, which represented 20% of the total recovery, took place during the first 15 s and occurred concomitantly with an increase in ATP from 3.9 to 4.6 mumol/g. Lactate concentration did not change significantly during this period. The second phase of recovery of contractile force was complete in 50 min. Lactate concentration and contractile force were significatly correlated during recovery (r = -0;92, P less than 0.00001). However, recovery of contractile force lagged behind the decrease in lactate; a given concentration of muscle lactate was associated with a higher contractile force early during development of fatigue than late during recovery.

Author List

Fitts RH, Holloszy JO

Author

Robert Fitts PhD Professor in the Biological Sciences department at Marquette University

MESH terms used to index this publication - Major topics in bold

Adenosine Triphosphate
Animals
Fatigue
Glycogen
Lactates
Muscle Contraction
Muscles
Phosphocreatine
Rana pipiens