Format

Send to

Choose Destination
Br J Sports Med. 2011 Nov;45(14):1132-6. doi: 10.1136/bjsm.2010.082677. Epub 2011 Mar 13.

Increased running speed and pre-race muscle damage as risk factors for exercise-associated muscle cramps in a 56 km ultra-marathon: a prospective cohort study.

Author information

1
Research Unit for Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, South Africa. martin.schwellnus@uct.ac.za

Abstract

BACKGROUND:

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.

PURPOSE:

The purpose of this prospective cohort study was to identify risk factors associated with the development of EAMC in ultra-distance runners.

METHODS:

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).

RESULTS:

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).

CONCLUSIONS:

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.

Comment in

PMID:
21402566
DOI:
10.1136/bjsm.2010.082677
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center