Physical Characteristics Of Ultra-marathon Distance Runners

Karolina Zavisiute, Anthony Hagele, Joesi Krieger, Kyle Sunderland, Petey Mumford, Chad Kerksick, FACSM, Scott Richmond Exercise and Performance Nutrition Laboratory, Lindenwood University, St. Charles, MO, USA Participation in long distance running events, specifically marathons and ultramarathons, has been growing at an incredible rate in the past two decades. As the number of participants has grown, so has the interest in learning more about the physiological differences between ‘typical’ distance runners (those running marathons and shorter distance races) from those running longer distance races such as ultramarathons. PURPOSE: The primary aim of this study is to explore physiological characteristics of non-elite ultramarathon runners and muscular changes after completion of a 100-mile trail race. METHODS: Within the two weeks preceding a 100-mile trail ultramarathon race, participants completed a test of aerobic capacity (VO2peak), muscle strength (isometric belt squat, IMBS), muscle power (countermovement jump, CMJ), and muscle structure (ultrasound). Within five days after the race, participants repeated the IMBS, CMJ and ultrasound. A total of 10 males (age = 36.6 ± 14.1y, height = 177.4 ± 7.2 cm, weight = 75.4 ± 7.1 kg, VO2peak = 52.8 ± 6.3 mL/kg/min) participated in this study. RESULTS: Seven participants finished the race with an average time of 26:10:36 hr:min:sec (range = 20:39:50 to 33:27:59 hr:min:sec). CMJ results showed significant changes (p = 0.007) in braking RFD (pre = 6570.0 ± 4832.3 N, post = 3914.7 ± 3036.9 N) as well as significant changes (p = 0.029) during force at peak braking force for both the left (pre = 823.8 ± 154.6 N, post = 716.9 ± 177.5 N) and right legs (pre = 816.5 ± 109.5 N, post = 746.6 ± 148.5 N). No other significant changes were observed in IMBS or ultrasound. CONCLUSION: The observed changes in power may be attributable to the rocky terrain of the racecourse, as well as the impact incurred during repeated downhill running. The physiological characteristics of non-elite ultramarathon runners are similar to individuals with average fitness levels.