8-week Resistance Exercise Training Ameliorates Acute Resistance Exercise-Related Impairments in Macrovascular Function in Middle-Aged Women

Background: Women experience a stark increase in hypertension risk in middle life, in part, due to concomitant aging and the loss of endogenous estrogen production with menopause. In young women, 8-week resistance exercise training (RT) ameliorates acute resistance exercise (RE)-related declines in macrovascular function, likely due to adaptation to large oscillations in blood pressure and blood flow during repeated bouts of acute RE. However, the effect of RT on vascular (macro and micro) function responses to acute RE in middle-aged women is unknown. Purpose: Evaluate the impact of 8-week RT on macro- and microvascular function responses to acute RE in middle-aged women. Hypothesis: It was hypothesized acute RE-related impairments in macrovascular function and increases in microvascular function would be ameliorated or augmented, respectively, following RT. METHODS: 22 middle-aged women (51±6y; 0y resistance training experience) completed 8-week RT. RT included 3 resistance exercise sessions per week for 8 weeks, and each session included three sets of 8-12 repetitions of eight total body resistance exercises at 60% of 1 repetition maximum (1RM). Weights were increased by 5-10% after two sets of 12 repetitions were performed for three consecutive sessions. Before and after 8-week RT, participants underwent macrovascular function (flow-mediated dilation, FMD) and microvascular function (reactive hyperemic area under the curve, RHAUC) assessment before and after one RE bout (acute RE). Acute RE consisted of three sets of 8-12 repetitions at 60-80% of 1RM for eight total body exercises. 2x2 repeated measures ANOVAs were used to compare vascular function responses to acute RE before and after 8-week RT, with factors of RE (pre-acute RE, post-acute RE) and 8-week RT (pre-8w RT, post-8w RT). RESULTS AND DISCUSSION: Leg press 1RM and chest press 1RM significantly increased following 8-week RT (ΔLeg Press 1RM: +63.3±29.3kg, p<0.0001; ΔChest Press 1RM: +8.2±5.1kg, p<0.0001). There was no effect of 8-week RT on resting macro- or microvascular function (FMD: 5.56±3.78% to 4.19±2.57%, p=0.08; RHAUC: 411.2±189.2ml/min to 420.6±167.8ml/min, p=0.82). Though there was a significant interaction effect of 8-week RT and acute RE on FMD (p=0.01), there were no differences in macrovascular function responses to acute RE (Pre-8w RT: 5.56±3.78% to 4.32±3.17%, p=0.14; Post-8w RT: 4.19±2.57% to 5.51±3.62%, p=0.11). Further, there was a significant interaction effect for FMD normalized to shear rate (FMD/SRAUC peak ) (p=0.009). Prior to 8-week RT, normalized FMD decreased after acute RE, but after 8-week RT, there was no difference in normalized FMD after acute RE (Pre-RT: 4.73±3.29%/s -1 *10 -3 to 3.43±2.40%/s -1 *10 -3 , p=0.045; Post-RT: 3.61±2.32%/s -1 *10 -3 to 4.48±2.69%/s -1 *10 -3 , p=0.22). Lastly, there was a significant effect of acute RE on microvascular function independent of 8-week RT; RHAUC significantly increased after acute RE before and after 8-week RT (Pre-RT: 411.2±189.2ml/min to 556.7±248.3ml/min, p=0.002; Post-RT: 420.6±168.9ml/min to 580.3± 213.1ml/min, p=0.0008). Conclusion: While the increases in microvascular function after acute RE are not impacted by 8-week RT in middle-aged women, the acute-RE related impairments in macrovascular function are ameliorated by 8-week RT, likely due to improved release and/or impact of vasodilatory metabolites. Husman Endowment (PI – Ranadive) This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.