Effect of exercise order of combined aerobic and resistance training on arterial stiffness in older men

Arterial stiffness increases with advancing age, and is as an emerging biomarker in the assessment of vascular health. Some studies suggest that high-intensity resistance training increases arterial stiffness, but low- to moderate-intensity resistance training does not effect on arterial stiffening. Current evidence suggests that performing aerobic exercise after resistance training improved arterial stiffness in the young men and women. However, few studies have been conducted on the effects of the order of combined training on arterial stiffness in the elderly. The purpose of this study was to examine the effects of exercise order of combined aerobic and resistance training into the same session on body composition, muscle strength and arterial stiffness in older men. Forty-five older men (aged 70.5 ± 3.5 years) were randomly assigned to 3 groups; AR: aerobic before resistance training, RA: resistance before aerobic training and CON: no training. Subjects trained 2 times per week for 10 weeks. Resistance training consisted of 3 sets of 8-12 repetitions for 5 different exercises, 70-80% of one repetition maximum (1RM). Aerobic exercise consisted of cycling at 60% of heart rate reserve (HRR). Significant interaction effects were observed in waist circumference (P < 0.01), grip strength (P < 0.01), 10-m walk speed (P < 0.05) and 1RM strength (P < 0.01). However, no significant differences were observed between AR and RA. In contrast, pulse wave velocity (PWV) significantly reduced in the RA (9.0 ± 1.6 m/s to 8.0 ± 1.6 m/s, P < 0.05), whereas, it did not change in the AR, and there was a significant group difference (P < 0.05). In conclusion, no effects of the exercise order were observed in body composition, physical fitness and muscle strength. However, aerobic exercise after high-intensity resistance training reduced arterial stiffness and difference of exercise order was observed. We suggest that the exercise order may favorably affect arterial stiffness when combined aerobic exercise and high-intensity resistance training is performed into the same session.