title: Are Electrically Induced Muscle Cramps Able to Increase the Cramp Threshold Frequency, When Induced Once a Week?
abstract: The cramp threshold frequency (CTF) is known to be positively correlated with the individual cramp susceptibility. Here we assessed CTF changes after two bouts of electrically induced muscle cramps (EIMCs). The EIMCs (6×5 sec) were unilaterally induced twice (separated by one week) in the gastrocnemius of an intervention group (n=8), while 5 participants served as control. The CTF increased from 25.1±4.6 Hz at baseline to 31.4±9.0 Hz and 31.7±8.5 Hz 24 h after bout 1 and 2 (P<0.05). Thereafter, the CTF declined following both bouts to reach values of 28.0±6.7 Hz and 29.1±7.7 Hz after 72 h after bout 1 and 2. Creatine kinase (CK) activity and perceived discomfort during cramps was lower after bout 2 (P<0.05). CTF, CK, and discomfort did not change in CG. That is, a single bout of EIMCs induces a 24 h CTF increment and a second bout sustains this effect, while perceived discomfort and muscle damage decreases. This short term effect may help athletes to reduce the cramp susceptibility for an important match.
authors.affiliation: Institute for Training Science and Sport Informatics, German Sport University of Cologne , Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Behringer
authors.affiliation: Institute for Training Science and Sport Informatics, German Sport University of Cologne , Germany.
authors.forename: Tobias Walter
authors.initials: TW
authors.lastname: Link
authors.affiliation: Institute for Training Science and Sport Informatics, German Sport University of Cologne , Germany.
authors.forename: Johannes Caspar Konrad
authors.initials: JC
authors.lastname: Montag
authors.affiliation: Institute for Training Science and Sport Informatics, German Sport University of Cologne , Germany.
authors.forename: Molly Leigh
authors.initials: ML
authors.lastname: McCourt
authors.affiliation: Institute for Training Science and Sport Informatics, German Sport University of Cologne , Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Mester
keywords: Electrically induced muscle cramps; cramp threshold frequency; muscle damage; perceived discomfort; repeated bout effect