High-intensity resistance exercise (RE) increases aortic stiffness and decreases the index of myocardial oxygen supply/demand balance (Buckberg index, BI); there is a correlation between the changes in these parameters. Central hemodynamics during diastole can explain the correlation. We aimed to investigate whether the aortic diastolic decay index mediates the association between changes in aortic stiffness and BI by high-intensity RE. We evaluated the effect of high-intensity RE on aortic stiffness, BI, aortic decay index, and their associations in 52 young men. Subjects were studied under parallel experimental conditions on two separate days. The order of experiments was randomized between RE (5 sets of 10 repetitions at 75% of 1-repetition maximum) and sham control (seated rest). Aortic pulse wave velocity (PWV; index of aortic stiffness), BI, and aortic decay index were measured in all subjects. Aortic decay index was quantified by fitting an exponential curve: P( t) = P0e−λ t (where λ is decay index, P0 is end-systolic pressure and t is time from end-systole). Aortic PWV and decay index increased and BI decreased after RE. RE conditions showed that change in the aortic decay index was associated with changes in aortic PWV and changes in aortic PWV were related to changes in BI, although the PWV-BI relationship was not significant after accounting for decay index change. Mediation analysis revealed the mediating effect of the aortic decay index on the relationship between changes in aortic PWV and BI. The present findings suggest that high-intensity RE-induced aortic stiffening worsens myocardial viability by accelerating aortic diastolic exponential decay. NEW & NOTEWORTHY Aortic pulse wave velocity (PWV) and diastolic decay index increased and Buckberg index (BI) decreased after resistance exercise (RE). Mediation analysis revealed a mediating effect of aortic decay index on the relationship between changes in aortic PWV and BI. The present study provides evidence that high-intensity RE-induced aortic stiffening accelerates aortic decay and aortic decay can account for the relationship between aortic stiffening and a deteriorated surrogate marker of myocardial oxygen supply/demand balance induced by high-intensity RE.

High-intensity resistance training decreases central arterial compliance (CAC). Subendocardial viability ratio (SEVR) is a useful tool that reflects the balance between coronary perfusion and left ventricular afterload. Animal studies have demonstrated that decreased CAC is associated with SEVR deterioration. Therefore, resistance training-induced decrease in CAC may be associated with changes in SEVR. The objective of the present study was to investigate the association between SEVR and CAC using both cross-sectional and longitudinal (i.e., resistance training) study designs. To achieve this, we first conducted a cross-sectional study to investigate the association between SEVR and CAC in 89 young men. Thereafter, a longitudinal study was performed to examine the effects of resistance training on SEVR and CAC in young men. A total of 28 young men were divided into 2 groups: control (n = 13) and training (n = 15). In the training group, subjects underwent supervised resistance training for 4 weeks (5 sets of 10 repetitions at 75% of 1-repetition maximum, 3 times/week). CAC and SEVR were then measured in all subjects. In the cross-sectional study, SEVR was significantly positively correlated with CAC, whereas resistance training significantly decreased both SEVR and CAC. Moreover, training-induced changes in CAC were significantly correlated with changes in SEVR. Thus, these results suggest that resistance training-induced decrease in CAC is associated with decreased SEVR in young men.

Objective:Coronary heart disease is the leading cause of mortality in women. Despite a higher risk of heart failure after the first myocardial infarction in women compared with men, the sex-specific mechanisms are unknown. We hypothesized that myocardial ischemia is attributable to sex-related diastolic alterations in the central hemodynamics.Methods:We investigated the subendocardial viability ratio (myocardial oxygen supply/demand) and aortic diastolic pressure decay index in 962 apparently healthy adults (mean age, 56 ± 10 years). Using noninvasive applanation tonometry, the subendocardial viability ratio, aortic diastolic pressure decay index, and aortic augmentation index were estimated in all participants. The aortic diastolic pressure decay index was quantified by fitting an exponential curve: P(t) = P0e−λt (λ, decay index; P0, end-systolic pressure; t, time from end-systole).Results:Women showed a significantly higher aortic diastolic pressure decay index, even after adjusting for age, hypercholesterolemia, and diabetes, and a significantly lower subendocardial viability ratio than men (P < 0.001). Analysis demonstrated a mediating effect of the aortic decay index on the sex-related differences in the subendocardial viability ratio (71%), despite different effects of the augmentation index (5%).Conclusion:These results suggest that the predisposition of women to coronary heart disease is more likely attributable to impaired myocardial perfusion caused by accelerated aortic diastolic pressure decay, rather than increased myocardial load due to augmented aortic systolic pressure.

Cerebral hemodynamics plays an important role in cognitive performance, and as such, age-related cognitive dysfunction and cerebral hypoperfusion increase the risk of dementia. However, age-related changes in cerebral oxygenation and cognitive function remain unclear. The aim of this study was to investigate age-related declines in cerebral oxygenation and executive function cross-sectionally. Ninety-eight healthy Japanese adults (age range: 23-79 years; 40 males, 58 females) participated in the present study using local advertisements. The participants were divided into 4 age groups: young (20-39 years; M15/F7), 50s (50-59 years; M10/F12), 60s (60-69 years; M9/F31), and 70s (70-79 years; M6/F8). We measured oxygenated hemoglobin (oxy-Hb) signal change in the prefrontal cortex during the Stroop task, and calculated Stroop interference time in cross-sectional design. This test is widely used to measure the ability to properly control attention and behavior in executing tasks, and to evaluate executive functions mainly associated with the prefrontal cortex. Oxy-Hb signal changes in the left prefrontal cortex in the 60s and 70s groups were significantly lower than those in the young group (both P < 0.05). Additionally, Stroop interference time was significantly longer in the 60s and 70s groups than in the young group (both P < 0.05). Furthermore, differences in oxy-Hb signal change between the left and right prefrontal cortex were evident only in the young group. These results suggest that the age-related decrease in executive function is associated with decrease in the cerebral oxygenation hemodynamics in the left prefrontal cortex.

Male sexual function is regulated by vascular function and impaired vascular function is closely related with erectile dysfunction (ED). Vascular functions are positively influenced by physical fitness (i.e., aerobic capacity, muscle strength, and flexibility). The detailed associations between physical fitness and male sexual function remain poorly understood. The present study aimed to clarify the influence of physical fitness on male sexual function. In 177 adult men, peak oxygen consumption (VO 2 peak ), handgrip strength (HGS), and sit and reach were measured as indices of physical fitness. Arterial stiffness and erectile function were assessed by carotid–femoral pulse wave velocity (cfPWV) and the International Index of Erectile Function 5 (IIEF5) questionnaire, respectively. IIEF5 score was significantly correlated with VO 2 peak ( r s = 0.52), HGS ( r s = 0.37), and cfPWV ( r s = −0.44); and multivariate linear regression analyses showed that VO 2 peak , HGS, and cfPWV were significantly associated with IIEF5 score after considering confounders. The receiver operator characteristic curve analysis suggested that the cutoff values for predicting ED were 29.0 ml/min/kg for VO 2 peak and 39.3 kg for HGS. The IIEF5 score was the highest in the subjects with the values of both VO 2 peak and HGS were higher than their respective cutoff values, while the IIEF5 score was the lowest in the subjects with the values of both VO 2 peak and HGS were lower than their respective cutoff values. These results suggest that the maintenance of high aerobic capacity and muscular strength may offset deterioration of male sexual function.