EXPLORING SEX DIFFERENCES ON ARTERIAL STIFFNESS IN RESPONSE TO HEAVY ROPE EXERCISE

Abstract

PURPOSE: To evaluate sex differences on aortic and carotid arterial stiffness, and carotid artery compliance (CAC), following heavy rope exercise (HRE). METHODS: Twenty-seven resistance-trained individuals (Men: n=14, Mean±SD: Age: 23 ± 3 yrs; Women: n=13, Age: 22 ± 2yrs) participated. All measurements were collected at Rest, and 15 (Rec1), 30 (Rec2), and 60 (Rec3) minutes following HRE. Aortic arterial stiffness was assessed by pulse wave velocity (PWV), while carotid arterial stiffness, via beta stiffness index (BSI), and CAC, were collected via Doppler ultrasound. HRE utilized six 15-second exercise bouts using a double wave pattern (180bpm), with 30-second seated recovery. Two-way repeated measures ANOVAs were used to determine differences in PWV, BSI, and CAC, between the sexes across time. RESULTS: Men had significantly greater height (p ≤ 0.001) and weight (p ≤ 0.001). There were no significant sex by time interactions for PWV (p = 0.96) or BSI (p = 0.09). A significant main effect of time (p ≤ 0.001) showed that PWV significantly increased during Rec1, however, returned to below resting value at Rec3 (Men= Rest: 5.9 ± 0.7 m/s, Rec1: 6.2 ± 0.7 m/s, Rec2: 6.0 ± 0.7 m/s, Rec3: 5.7 ± 0.7 m/s; Women= Rest: 5.3 ± 0.8 m/s, Rec1: 5.7 ± 0.9 m/s, Rec2: 5.3 ± 0.7 m/s, Rec3: 5.1 ± 0.5 m/s). A main effect of time for BSI (p = 0.002) showed a significant increase during Rec1 and Rec2 from Rest, while Rec3 returned to Rest (Men= Rest: 3.2 ± 1.1 units, Rec1: 4.0 ± 1.5 units, Rec2: 3.5 ± 1.6 units, Rec3: 3.3 ± 1.5 units; Women= Rest: 2.6 ± 1.0 units, Rec1: 3.6 ± 1.6 units, Rec2: 4.3 ± 1.7 units, Rec3: 2.4 ± 0.8 units). There was a significant sex by time interaction for CAC (p = 0.05). Men did not significantly change across time, however, from Rest women significantly decreased during Rec2, then significantly increased from Rec2 to Rec3 (Men= Rest: 0.2 ± 0.1 mm2/mmHg, Rec1: 0.2 ± 0.1 mm2/mmHg, Rec2: 0.2 ± 0.1 mm2/mmHg, Rec3: 0.2 ± 0.1 mm2/mmHg; Women= Rest: 0.3 ± 0.1 mm2/mmHg, Rec1: 0.2 ± 0.1 mm2/mmHg, Rec2: 0.2 ± 0.1 mm2/mmHg, Rec3: 0.3 ± 0.1 mm2/mmHg). CONCLUSIONS: These data suggest that HRE does not produce differences in aortic or carotid arterial stiffness between sexes. The initial decrease in women’s CAC is likely due to greater relative intensity, while the increase in CAC back to resting values is potentially due to the cardioprotective effects of estrogen.