Does lifting heavier or lighter weights change blood pressure in older women?

The goal of the clinical trial is to understand the effect of two resistance training protocols employing different loading intensities (% of 1 repetition maximum; 1-RM), but with standardized effort intensity (2 repetitions in reserve; RIR) on post-exercise and ambulatory blood pressure in aging females.

The main questions it aims to answer are:

• to examine the acute effects of low (50% 1-RM) and high (80% 1-RM) load intensity resistance exercise with a standardized high effort intensity on post-exercise hypotension and ambulatory blood pressure responses in aging females;
• deepen the understanding of the mechanisms underlying acute reductions in blood pressure in response to resistance exercise performed at different load intensities. To this end, autonomic activity will be estimated alongside the measurement of central arterial compliance (i.e., carotid artery), and serum biomarkers of endothelial function;
• document the affective valence and enjoyment associated with low (50% 1-RM) and high (80% 1-RM) load intensity resistance exercise when performed at a high perceived effort.

Researchers will compare the effect of: 1) a low load (LL-RE) intensity protocol consisting of 3 sets of each exercise at 50% 1-RM, performed until reaching a hard perceived effort intensity (i.e., RIR-2); 2) high load (HL-RE) intensity protocol consisting of 3 sets of each exercise at 80% of 1-RM, performed until reaching a hard perceived effort intensity (i.e., RIR-2); 3) and a control condition (CON) consisting of a standardized non-fatiguing cognitive task.

Participants will participate in:

• A preliminary assessment visit;
• Two familiarization visits to validate the exercise prescriptions;
• Three experimental visits (CON, LL-RE, HL-RE).