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.