Effects of Neuromuscular Electrical Stimulation on the Frequency of Skeletal Muscle Cramps: A Prospective Controlled Clinical Trial

• Published in: Neuromodulation (Malden, Mass.) Vol. 21; no. 8; pp. 815 - 822
• Main Authors: Behringer, Michael, Harmsen, Jan‐Frieder, Fasse, Alessandro, Mester, Joachim
• Format: Journal Article
• Language: English
• Published: United States Elsevier Limited 01.12.2018
• Subjects: Adult; Aged; Calf muscles; Clinical trials; cramp prevention; cramp threshold frequency; Electric Stimulation Therapy - methods; Electrical stimuli; Humans; Leg; Male; Middle Aged; Muscle Cramp - prevention & control; Muscle pain; Muscle, Skeletal - physiopathology; Neuromuscular electrical stimulation; Skeletal muscle; cramp prevention; cramp threshold frequency; Calf muscles
• ISSN: 1094-7159; 1525-1403
• DOI: 10.1111/ner.12728

Objectives We investigated if neuromuscular electrical stimulation (NMES) of calf muscles prevents spontaneous calf cramps. Materials and Methods In 19 individuals affected by more than or equal to one calf cramp per week the gastrocnemius of the predominantly affected leg was stimulated twice a week (intervention leg, IL) over six weeks (3 × 6 stimulation trains at 30 Hz above the individual cramp threshold frequency). The other leg served as control (CL). The participants were advised to record all spontaneous muscle cramps from two weeks before the intervention until two weeks after the last NMES session. Results The number of spontaneous calf cramps in the two weeks after the intervention was 78% lower (2.1 ± 6.8 cramps) in the stimulated (p < 0.001) and 63% lower (2.0 ± 6.9 cramps) in the unstimulated calves (p < 0.001), when compared to the two weeks prior to the intervention (IL: 9.6 ± 12.4 cramps; CL: 5.5 ± 12.7 cramps). Only in the IL, this improvement was accompanied by an increase in the cramp threshold frequency from 15.5 ± 8.5 Hz before the NMES intervention to 21.7 ± 12.4 Hz after the intervention. The severity of the remaining calf cramps tended to be lower in both legs after the intervention. Conclusions The applied stimulation protocol seems to provide an effective prevention strategy in individuals affected by regular calf cramps.