Cardiovascular responses to cold and exercise in patients with coronary artery disease

Regular physical exercise is important both for the prevention of coronary artery disease (CAD), but also for its treatment, and rehabilitation. However, exercise during winter can elicit cardiac symptoms, such as arrhythmias and chest pain or increase the risk of adverse health events. It is known, that both cold exposure and moderate sustained exercise separately increase cardiac workload, but their combined effects on cardiovascular responses are not well known. The controlled study examined the effect of wintertime exercise on cardiovascular function among CAD patients.

The study participants consisted of 4070 years-old men who had experienced a myocardial infarction and been diagnosed with CAD. During the first phase of the controlled study a total of 20 participants walked briskly and rested in neutral (+22 °C) and cold (-15 °C) conditions. In the second protocol, 20 participants performed static (arm crank, sustained power) and dynamic (pedaling with arms) upper-body exercise at the same temperatures.

The study demonstrated that dynamic and static exercise performed in a cold environment increases cardiac workload of stable CAD patients by ca. 20% compared with the corresponding exercise in a neutral environment. However, no signs of myocardial ischemia or other abnormal ECG changes were observed. In general, moderate lower and upper-body exercise reduced post-exercise central aortic BP regardless of temperature, except after static exercise in the cold. The results indicate that stable CAD patients probably benefit from year-round regular dynamic exercise, but the cardiovascular responses following static exercise in the cold should be examined further.