TARAHUMARA INDIAN RUNNERS' HEARTS RECOVER FULLY WITHIN 24 HOURS OF AN ULTRA-DISTANCE RACE AT ALTITUDE
Christensen, D. L., Espino, D., Cervantes, M., Infante, R., Hassager, C., & Kjaergaard, J. (2013). Echocardiographic assessment of the heart in ultra-distance running at altitude in Mexican Tarahumara Indians. Medicine & Science in Sports & Exercise, 45(5), Supplement abstract number 1971.
"Ultra-endurance exercise results in remodeling of the left and the right ventricles; however, to what extent the cardiac muscle of athletes exposed to life-long endurance exercise at altitude recover structurally and functionally following an ultra-distance race has yet to be determined. The Mexican Tarahumara Indians are known to run extremely long distances in mountainous terrain beginning from early adolescence; they may thus represent the ultimate adaptive cardiac remodeling in athletes."
This study determined acute (24-hour) cardiac recovery following an ultra-distance race at altitude in adult male Mexican Tarahumara Indians (N = 8). Echocardiographic measurements were performed before and at <30 minutes, six hours, and 24 hours following a 63 km race at 2,400 m altitude. Heart rate, cardiac output (from velocity time integral of the left-ventricular outflow tract flow), left-ventricle end-diastolic volume, left-ventricle ejection fraction, right-ventricle fractional area change, right-ventricle peak systolic annular velocity, left-ventricle and right-ventricle global longitudinal strain, and right-ventricle mid-wall longitudinal strain were measured.
Mean running time was 7.10:00 (range 5.51:00 to 8.05:00). Heart rate was elevated at <30 minutes and six hours post-race, and cardiac index was elevated <30 minutes post-race. Left-ventricle end-diastolic volume had declined at <30 minutes post-race, and left-ventricle ejection fraction had declined at <30 minutes and six hours post-race. Right-ventricle fractional area change and right-ventricle peak systolic annular velocity had declined at <30 minutes. All echocardiographic measures of left-ventricle and right-ventricle remodeling had recovered fully 24 hours post-race.
Implication. Male Tarahumara Indian runners show well-established functional and structural cardiac responses immediately following ultra-distance running. They exhibit full heart recovery within 24 hours post-race.