The effects of strength training on central arterial compliance in middle-aged and older adults

BACKGROUND: Contrary to aerobic exercise, strength training (ST) is associated with decreased central arterial compliance in young men. It is unknown whether ST, with or without concurrent endurance training, would have a similar effect in older adults with reduced baseline arterial compliance. OBJECTIVE: The primary aim of this study was to determine the effect of a ST program on central arterial compliance in middle-aged and older adults. DESIGN: Randomized, controlled intervention study in which 37 healthy, sedentary men and women (52+/-2 years) performed 13 weeks of ST (n=13), ST+aerobic exercise (n=12) or stretching exercises as a control group (n=12). METHODS: Participants were rigorously screened for cardiovascular disease and underwent pre-post testing for carotid arterial compliance (via simultaneous ultrasound and applanation tonometry), carotid-femoral pulse wave velocity, plasma endothelin-1 and angiotensin II concentrations and carotid artery vasoreactivity (cold pressor test). RESULTS: ST performed alone, or in conjunction with aerobic exercise, improved maximal muscle strength and increased total lean body mass (both P<0.01). No significant changes were observed in carotid artery compliance or carotid-femoral pulse wave velocity following ST or ST+aerobic exercise. Carotid artery compliance increased significantly (23%) following stretching which may be attributed to a reduction in carotid pulse pressure. No significant changes were observed in plasma vasoconstrictor hormones or carotid artery vasoreactivity following the interventions. CONCLUSION: Thirteen weeks of moderate ST two or three times per week does not reduce central arterial compliance in middle-aged and older adults.