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The benefits of regular exercise for wellbeing and health during all stages of life are unambiguous. Physical exercise is therefore crucial for the prevention, treatment, and rehabilitation of coronary artery disease (CAD). A cold environment can induce cardiac symptoms or increase the risk of adverse health events. However, the combined effects of cold and moderate sustained exercise, both known to increase cardiac workload, on cardiovascular responses are not well known. We conducted two four-period cross-over trials. In the first protocol, we selected 20 CAD patients, who performed moderate-intensity lower-body exercise (walking at 65‐70% of HR max) and rested in neutral (+22 °C) and cold (-15 °C) conditions. In the second protocol, CAD patients (n=20) performed static (five 1.5-min work cycles, 10‐30% of maximal voluntary contraction) and dynamic (three 5-min workloads, 56‐80% of HR max) upper-body exercise at the same temperatures. Both trials consisted of four 30-min exposure periods administered in randomized order. Brachial, central aortic, and continuous blood pressure (BP), as well as electrocardiography (ECG) and skin temperature, were measured. The combined effects of cold and lower-body dynamic exercise increased rate pressure product (RPP) by 17% compared with neutral conditions (p=0.001). This was primarily due to sustained higher systolic BP, but also a slightly increased heart rate (HR). Dynamic graded upper-body exercise in the cold increased RPP by 18.1‐24.4% (p=0.002–0.020), whereas RPP during static exercise remained unaltered due to decreased HR (4.1‐7.2%; p=0.009‐0.033). Post-exercise central systolic BP decreased by 2‐10 mmHg (p |
