Eccentric exercise improves myocardial oxygen supply/demand balance with decelerating aortic diastolic pressure decay: The acute and chronic studies

ABSTRACT Both eccentric (ECC) and concentric (CON) exercises improve energy expenditure and blood lipid profile. Although ECC exercise has a more beneficial effect on these factors than CON exercise, its benefits on vital organs are still unclear. This study investigated the mode‐of‐action‐dependent effects on myocardial perfusion index. Seventeen healthy men (age: 26 ± 5 years) were randomly enrolled in CON (n = 9) and ECC (n = 8) groups. Transient exercise and regular training (three‐day a week for 4‐week) included bicep curl comprising 5‐set of 10‐repetition, each using 75% one‐repetition maximum concentric loading. The ECC group performed one‐repetition of ECC for 3‐s and CON for 1‐s, while the CON group performed one‐repetition of CON for 3‐s and ECC for 1‐s. All participants were assessed for subendocardial viability ratio (SEVR, myocardial perfusion index) and aortic diastolic pressure decay. Before study, these were found to be same for both groups. Transient (ΔSEVR: 20.3 ± 13.3%, p = 0.01; Δdecay: −0.07 ± 0.02 s−1, p < .001) and regular (ΔSEVR: 18.5 ± 12.8%, p = .001; Δdecay: −0.06 ± 0.05 s−1, p = .004) ECC (but not CON) exercises significantly increased SEVR and decelerated decay. Increased SEVR with ECC exercise was associated with decelerated decay (transient ECC: r2 = 0.56, 95% confidence interval [CI] = −0.95 to −0.10, p = .03; regular ECC: r2 = 0.53, 95% CI = −0.95 to −0.05, p = .04). These findings suggest that ECC exercise improves myocardial perfusion and diastolic pressure contour is involved in physiological mechanisms.