Hunter Gary R, Fisher Gordon, Carter Stephen J, Moellering Douglas R
Department of Nutrition Sciences, School of Health Professions, University of Alabama at Birmingham, 1675 University Blvd, Susan Mott Webb Building Suite 439, Birmingham, AL, 35233, USA.
Deparment of Human Studies, School of Education and Human Sciences, University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
Eur J Appl Physiol. 2025 May 10. doi: 10.1007/s00421-025-05805-2.
Previously we have shown that systolic blood pressure (SBP) increases in African American (AA) women but decreases in European American (EA) women ≈22 h after a high-intensity exercise bout, suggesting delayed recovery in the AA women. We, therefore, sought to determine whether myofiber type, systemic vascular resistance (SVR), and mitochondrial coupling efficiency may contribute to elevated blood pressure in AA women following a bout of high-intensity exercise. Premenopausal EA (9) and AA (7) women were aerobically trained for 8-16 weeks and was evaluated. After 2 days without exercise, participants were evaluated for myofiber type, mitochondrial respiration using high-resolution respirometry, and SVR 22 h following 1 h of high-intensity interval cycle ergometry. AAs had higher SBP and DBP and type IIx myofiber % but lower type IIa myofiber %. SBP was significantly related to SVR (0.71), RCR (0.44), type IIa myofiber type (- 0.48), and type IIx myofiber type (0.53). DBP was significantly related to SVR (0.58) and the respiratory acceptor control ratio (state 3/state 4, termed RCR, 0.69). SBP remained significantly higher in AAs even after adjusting for type IIx myofiber type, RCR, SVR, or adjusted for FFM, and additionally, DBP remained significantly higher after adjusting for type IIx myofiber type, RCR, or adjusted for FFM. These results support the premise that mitochondrial RCR, type IIx myofiber type, and SVR may contribute to increased blood pressure ≈22 h following a bout of high-intensity exercise. Still, racial differences were not explained by any of these variables.
此前我们已经表明，在进行一轮高强度运动后约22小时，非裔美国（AA）女性的收缩压（SBP）会升高，而欧美（EA）女性的收缩压则会下降，这表明AA女性的恢复延迟。因此，我们试图确定肌纤维类型、全身血管阻力（SVR）和线粒体偶联效率是否可能导致AA女性在一轮高强度运动后血压升高。对绝经前的EA（9名）和AA（7名）女性进行了8 - 16周的有氧训练并进行评估。在2天不运动后，对参与者进行肌纤维类型评估，使用高分辨率呼吸测定法评估线粒体呼吸，并在进行1小时高强度间歇循环测力计运动后22小时评估SVR。AA女性的SBP和舒张压（DBP）较高，IIx型肌纤维百分比更高，但IIa型肌纤维百分比更低。SBP与SVR（0.71）、呼吸控制率（RCR，0.44）、IIa型肌纤维类型（-0.48）和IIx型肌纤维类型（0.53）显著相关。DBP与SVR（0.58）和呼吸受体控制率（状态3/状态4，称为RCR，0.69）显著相关。即使在调整了IIx型肌纤维类型、RCR、SVR或调整了去脂体重（FFM）后，AA女性的SBP仍然显著更高，此外，在调整了IIx型肌纤维类型、RCR或调整了FFM后，DBP仍然显著更高。这些结果支持这样一个前提，即线粒体RCR、IIx型肌纤维类型和SVR可能导致在一轮高强度运动后约22小时血压升高。不过，这些变量均无法解释种族差异。
