Kevin C Miller1, Blaine C Long1, Jeffrey E Edwards2. 1. Central Michigan University, School of Rehabilitation and Medical Sciences, 1208 Health Professions Building, Mount Pleasant, Michigan, USA. 2. School of Health Sciences, Mount Pleasant, Michigan, USA.
Abstract
INTRODUCTION: Muscle cramping may increase peripheral nervous system excitability. It is unknown if, and how long, cramp susceptibility is affected by previous cramping. We tested whether volitionally induced muscle cramps (VIMCs) lowered cramp threshold frequency (TFc ) and how long TFc was affected post-VIMC. METHODS: Fifteen cramp-prone participants volitionally induced a flexor hallucis brevis (FHB) cramp on 4 separate days. FHB TFc was measured before VIMC (i.e., baseline) and 5, 30, and 60 min post-VIMC. VIMC electromyography (EMG) amplitude, VIMC duration, andperceived VIMC intensity were measured to ensure consistency of VIMC between days. RESULTS:VIMC EMG amplitude, duration, and perceived intensity were similar between days (P > 0.05). VIMC lowered TFc ; baseline TFc (18 ± 6 Hz) was higher than 5-min (14 ± 6 Hz), 30-min (14 ± 5 Hz), and 60-min TFc (14 ± 5 Hz; P < 0.05). DISCUSSION: Acute VIMCs increase cramp susceptibility. Clinicians should apply treatments for at least 60 min postcramp to decrease the probability of cramp recurrence. Muscle Nerve 56: E95-E99, 2017.
RCT Entities:
INTRODUCTION: Muscle cramping may increase peripheral nervous system excitability. It is unknown if, and how long, cramp susceptibility is affected by previous cramping. We tested whether volitionally induced muscle cramps (VIMCs) lowered cramp threshold frequency (TFc ) and how long TFc was affected post-VIMC. METHODS: Fifteen cramp-prone participants volitionally induced a flexor hallucis brevis (FHB) cramp on 4 separate days. FHB TFc was measured before VIMC (i.e., baseline) and 5, 30, and 60 min post-VIMC. VIMC electromyography (EMG) amplitude, VIMC duration, and perceived VIMC intensity were measured to ensure consistency of VIMC between days. RESULTS:VIMC EMG amplitude, duration, and perceived intensity were similar between days (P > 0.05). VIMC lowered TFc ; baseline TFc (18 ± 6 Hz) was higher than 5-min (14 ± 6 Hz), 30-min (14 ± 5 Hz), and 60-min TFc (14 ± 5 Hz; P < 0.05). DISCUSSION: Acute VIMCs increase cramp susceptibility. Clinicians should apply treatments for at least 60 min postcramp to decrease the probability of cramp recurrence. Muscle Nerve 56: E95-E99, 2017.
Authors: Kevin C Miller; Brendon P McDermott; Susan W Yeargin; Aidan Fiol; Martin P Schwellnus Journal: J Athl Train Date: 2021-06-29 Impact factor: 2.860