Research Unit for Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, South Africa.
Br J Sports Med. 2011 Nov;45(14):1132-6. doi: 10.1136/bjsm.2010.082677. Epub 2011 Mar 13.
Despite the high prevalence of exercise-associated muscle cramping (EAMC) in endurance runners, the aetiology and risk factors for this condition are not fully understood.
The purpose of this prospective cohort study was to identify risk factors associated with the development of EAMC in ultra-distance runners.
49 runners participating in a 56 km race completed a validated pre-race questionnaire. Pre-race muscle pain in the calves, hamstrings and quadriceps muscles was recorded (visual analogue scale) and pre-race serum creatine kinase (CK) activity was measured. 20 runners reported EAMC (EAMC group) during or within 6 h after the event, while 29 runners reported no cramping (CON group).
EAMC was not associated with age, body mass index, sex, recent and past personal best running times, pre-race muscle pain and pre-race training (duration and frequency). Runners in the EAMC group tended to report on average longer training sessions during the 3 days before the race (EAMC 1.2 (1.1), CON 0.6 (1.0); p=0.077). Significant risk factors for EAMC were a past history of EAMC (EAMC 100%, CON 48%; p<0.001) and a faster running time (min) for the first 28 km split time of the race (EAMC 144 (20), CON 157 (14); p=0.029) despite being matched for recent (<15 weeks before race) personal best times in the 42.2 km race. Pre-race CK activity tended to be higher in the EAMC group (EAMC 89 (80), CON 58 (35); p=0.066).
Novel risk factors for EAMC in distance runners are a past history of EAMC, faster running pace at the early stage of a race and possibly pre-race muscle damage.
尽管耐力跑者中肌肉痉挛（EAMC）的发病率很高，但这种疾病的病因和危险因素尚未完全清楚。
本前瞻性队列研究旨在确定与超长跑运动员 EAMC 发展相关的危险因素。
49 名参加 56 公里比赛的运动员完成了一份经过验证的赛前问卷。记录赛前小腿、腿筋和四头肌的肌肉疼痛（视觉模拟评分），并测量赛前血清肌酸激酶（CK）活性。20 名运动员在比赛中或赛后 6 小时内报告出现 EAMC（EAMC 组），而 29 名运动员报告没有抽筋（CON 组）。
EAMC 与年龄、体重指数、性别、最近和过去的个人最佳跑步时间、赛前肌肉疼痛和赛前训练（持续时间和频率）无关。EAMC 组的运动员在比赛前 3 天的训练时间平均较长（EAMC 1.2（1.1），CON 0.6（1.0）；p=0.077）。EAMC 的显著危险因素是过去 EAMC 病史（EAMC 100%，CON 48%；p<0.001）和比赛前 28 公里分段时间的更快跑步速度（min）（EAMC 144（20），CON 157（14）；p=0.029），尽管在 42.2 公里比赛中最近（比赛前 15 周内）的个人最佳时间匹配。EAMC 组的赛前 CK 活性偏高（EAMC 89（80），CON 58（35）；p=0.066）。
长跑运动员 EAMC 的新危险因素是过去有 EAMC 病史、比赛早期跑步速度更快以及可能的赛前肌肉损伤。
