Precondizionamento ischemico non migliora la prestazione in atleti mezzofondisti in una prova sui 5000 metri di “self paced exercise”

The ischemic preconditioning (IP) is a protective phenomenon against cell injury induced by infarction. Furthermore, muscle IP has been found capable of improving exercise performance in laboratory testing. This investigation aimed at verifying the hypothesis that IP improved performance during self-paced exercise (SPE) in the field. 11 healthy male well trained runners performed three randomly assigned 5000 m self-paced running test in a regular athletic track. One was the reference (RT) test, while the others where performed after muscle IP (IPT) and a control sham test (ST). Average speed was measured during each test. Moreover, mean values of heart rate (HR), oxygen uptake (VO2), aerobic energy cost (AEC), and blood lactate (BLa) after race were gathered. We found that none of the studied variables were affected neither by IPT nor by ST with respect to the RT test. In detail, speed was on average 4.78±0.49, 4.84±0.85, and 4.53±0.38 m·s-1 for the RT, the ST, and the IPT test respectively. HR was 176.4±8.8, 173.8±5.4, and 175.4±5.8 bpm. VO2 was 3.5±0.69, 3.74±0.85, and 3.62±1.19 l·min-1. AEC was 1.04±0.15, 1.08±0.1, and 1.09±0.15 kcal·kg-1·km-1. Finally, BLa after races reached a level of 12.85±3.54, 11.88±4.74, and 12.82±3.6 mmol·l-1. Findings of the present investigation indicate that ischemic preconditioning is not capable to ameliorate performance during self paced exercise in the field. These results are in contrast to what previously found in the laboratory setting.