Effect of External Counterpulsation (ECP) on Delayed Onset Muscle Soreness (DOMS) in Long Distance Runners

External counterpulsation (ECP) has previously been used in treating cardiac patients. Compression of the lower extremities during diastole increases venous return and coronary perfusion. Purpose: To determine if ECP affects delayed onset muscle soreness (DOMS) and markers of muscle inflammation and skeletal muscle damage. Methods: Ten trained runners, 5 males and 5 females, aged 30.5 ł 12.8 years ran 20 miles at 70 of their VO2 max on a pre-determined course on two different occasions, once under control conditions and once under ECP treatment conditions. Conditions were randomly assigned to eliminate order effect. Perceived leg pain and blood markers (creatine kinase, CK lactate dehydrogenase, LDH and C-reactive protein, CRP were measured pre-run, immediate post-run and for 5 consecutive days post-control and ECP treatment runs. During the treatment condition, subjects received 60 minutes of ECP post-run and everyday for 5 days post-run. To control for effects of ECP 5 additional subjects aged 25.6 ł 2.1 years received 5 days of ECP treatment while remaining inactive. Repeated measures ANOVA was used to assess treatment effects. Protected t-tests were used to assess serial differences. Correlations were obtained to assess relationships between dependent variables. Repeated measures ANOVA were also used to assess gender differences in the control run and treatment run. Results: There was no significant difference in mean weight loss, fluid intake, exercise heart rate, percentage of maximum heart rate or maximal oxygen consumption (VO2) achieved, or running time between the control and ECP treatment runs. All indicators of muscle damage (CK, LDH, CRP, and pain) increased over time for the two runs, although there were no significant changes in the control group receiving ECP treatment only. CRP, pain, and LDH significantly decreased by two, one, and one day(s) post-ECP treatment, respectively, compared to the control condition. CK remained significantly elevated longer (3 days) in the ECP treatment r