Abstract 404: The Effects of Resistance Training and Weight Loss on Arterial Stiffness in Older Adults

Abstract

Aging and obesity are associated with increased arterial stiffness. While exercise and weight loss may have beneficial effects, the effect of resistance training (RT) on arterial stiffness is unclear, particularly in older adults. PURPOSE: We examined the effects of RT with and without weight loss on arterial stiffness in 32 overweight and obese older adults (mean age = 68±3 yrs; BMI = 31.1±2.7 kg/m2, 56% female, 13% Black). METHODS: Participants were randomly assigned to either RT only (n=16) or RT + caloric restriction (RT+CR, n=16). Participants in each group underwent supervised moderate-intensity RT (i.e. 70% one-repetition maximum) 3 days per week for 20 weeks. Arterial stiffness was measured using tonometry, impedance cardiography and oscillometry to assess changes in brachial-ankle pulse wave velocity (baPWV), augmentation index (Alx), large and small artery elasticity and total arterial compliance. RESULTS: Overall baseline mean values for the arterial stiffness measures were as follows: total arterial compliance = 18.1±6.8 ml/mmHg, baPWV = 1521±277 cm/s, large artery elasticity = 14.6±5.4 ml/mmHg x 10, small artery elasticity = 4.3±2.2 ml/mmHg x 100, and AIx = 30.8±8.3%. As expected, body weight was significantly reduced in the RT+CR group (-6.0±1.2 kg, p<0.0001) compared to RT only (0.2±1.2 kg, p<0.0006 for comparison). In models adjusted for age, gender, and baseline arterial stiffness, we found that total arterial compliance decreased in the RT only group, but did not change in the RT+CR group (-2.4±1.2 ml/mmHg vs. 0.5±1.1 ml/mmHg respectively, p=0.09). On the other hand, both large artery elasticity (2.7±1.5 ml/mmHg x 10) and augmentation index (4.0±2.2%) increased in the RT+CR group, with no changes in the RT only group. No significant changes were observed for baPWV or small artery elasticity in either group. Overall, greater reductions in body weight were correlated with greater increases in large artery elasticity (r=-0.29, p=0.11), but no other arterial stiffness measures. CONCLUSION: Our data suggest that adding weight loss to a RT program may lead to greater increases in large artery elasticity in overweight and obese older adults. These changes could potentially contribute to improvements in cardiovascular health.