1 3 Eur J Appl Physiol (2014) 114:1385–1392 DOI 10.1007/s00421-014-2869-y ORIGINAL ARTICLE Acute effects of continuous and interval low-intensity exercise on arterial stiffness in healthy young men Hailin Wang · Taiming Zhang · Weili Zhu · Hao Wu · Shoufu Yan Received: 1 July 2013 / Accepted: 4 March 2014 / Published online: 19 March 2014 © Springer-Verlag Berlin Heidelberg 2014 Conclusion Both acute continuous and interval low-inten- sity exercise elicits transient improvement in systemic arte- rial stiffness in humans. Despite equivalent exercise inten- sity and duration, interval exercise resulted in improved arterial stiffness for longer duration. Keywords Continuous exercise · Interval exercise · Low intensity · Arterial stiffness Abbreviations baPWV Brachial-ankle pulse wave velocity BL Baseline BMI Body mass index BP Blood pressure CAVI Cardio-ankle vascular index CE Continuous exercise CON Control DIA Diastolic blood pressure HIT High-intensity interval training HRR Heart rate reserve IE Interval exercise LB Left brachial RB Right brachial SYS Systolic blood pressure Introduction According to recommendation from expert bodies, adults should pursue moderate- or vigorous-intensity aerobic physical activity to keep and improve health (Haskell et al. 2007). In 2011, the American College of Sports Medicine proposed that people who are unwilling to meet the exer- cise targets still can benefit from engaging in amounts of exercise less than recommended (Garber et al. 2011). In Abstract Purpose To examine and compare systemic arterial stiff- ness responses in humans to acute continuous and interval low-intensity exercise. Methods Fifteen healthy young men (21.2 ± 0.4 years) underwent non-exercise control (CON), continuous exer- cise (CE), and interval exercise trial (IE) in a randomized balanced self-control crossover design. Systemic arte- rial stiffness (Cardio-ankle vascular index, CAVI) was measured at baseline (BL), immediately after (0 min) and 40 min after exercise in CE and IE trials, and at correspond- ing time points in CON trial. Subjects cycled continuously for 30 min at 35 % heart rate reserve after BL measurement in CE trial, whereas in IE trial, subjects cycled two bouts of 15-min separated by a 20-min rest at the same intensity. Results There were no significant CAVI changes with time in CON trial (6.7 ± 0.1, 6.7 ± 0.1, 6.6 ± 0.1 at BL, 0 and 40 min, respectively). In CE trial, CAVI decreased immediately after exercise (0 min) and returned to baseline after 40 min of recovery (6.5 ± 0.1, 5.5 ± 0.2, 6.4 ± 0.1 at BL, 0 and 40 min, respectively). IE elicited similar CAVI reduction from 6.7 ± 0.1 at baseline to 5.6 ± 0.2 at 0 min: however, CAVI at 40 min remained significantly low com- pared to that of CON trial at corresponding time point (6.0 ± 0.1 vs. 6.6 ± 0.1, P < 0.001). Communicated by Massimo Pagani. H. Wang and T. Zhang contributed equally to this study. H. Wang · T. Zhang · W. Zhu (*) · H. Wu · S. Yan Cardiovascular Health Laboratory, Capital University of Physical Education and Sports, 11 Bei San Huan Xi Road, Beijing 100191, People’s Republic of China e-mail: weili_zhu@163.com