Impact of resistance training and chicken intake on vascular and muscle health in elderly women.

Background: Resistance training is a well-known exercise therapy for preventing and improving lacks of muscle mass, strength, and quality with advances in age; however, its effects on arterial stiffness are not beneficial. Additionally, a higher intake of protein, which is an effective nutrient for muscle health, results in lower arterial stiffness. Whether the combination of moderate to high-intensity resistance training and high-protein intake would improve muscle mass, strength, and quality and cancel the resistance training-induced increase in arterial stiffness in elderly women remains unclear.

Methods: Ninety-three elderly women (67.2 ± 5.3 years) were randomly divided into four groups; sedentary control (CON), higher dietary animal protein intake (HP), resistance training (RT), and combination of RT and HP (RT + HP) groups. Participants in the RT and RT + HP groups completed 12 weeks of resistance training (exercise intensity at 70% of one-repetition maximum (1-RM), three sets with 10 repetitions of leg extension and curls, 3 days/week). In addition to the daily diet, the HP and RT + HP groups consumed steamed chicken breast as a high-protein diet.

Results: Percent changes in thickness (indices of muscle mass) and echo intensity (index of muscle quality) in the quadriceps muscle, 1-RM of leg extension and curls (index of muscle strength), and circulating C1q levels (a potential biomarker of muscle fibrosis) in the RT and RT + HP groups significantly improved after both RT and RT + HP interventions (P < 0.05). Percent changes in carotid-femoral pulse wave velocity (cfPWV) and carotid β-stiffness (indices of arterial stiffness), and circulating angiotensin II (a vasoconstrictor peptide hormone) levels via each intervention were significantly higher in the RT group (4.9 ± 12.7%, 13.8 ± 13.5%, 94.9 ± 132.7%, respectively), as compared with the CON group (-2.5 ± 5.9%, 0.2 ± 8.1%, 21.2 ± 79.3%, respectively) (P < 0.05). Of note, no significant differences in the cfPWV, carotid β-stiffness, and circulating angiotensin II levels between the RT + HP (-2.4 ± 9.3%, 2.4 ± 10.3%, -5.7 ± 29.6%, respectively) and CON groups were observed. Furthermore, significant positive relationships between the percent changes in circulating angiotensin II levels, and cfPWV (r = 0.438, P < 0.01) and carotid β-stiffness (r = 0.328, P < 0.01) were observed.

Conclusions: The combination of moderate to high-intensity resistance training and regular intake of steamed chicken breast as a high-protein food could increase muscle mass, strength, and quality and could cancel resistance training-induced increases in arterial stiffness in elderly women.