Cardiovascular responses to dynamic and static upper-body exercise in a cold environment in coronary artery disease patients.

PURPOSE

Upper-body exercise performed in a cold environment may increase cardiovascular strain, which could be detrimental to patients with coronary artery disease (CAD). This study compared cardiovascular responses of CAD patients during graded upper-body dynamic and static exercise in cold and neutral environments.

METHODS

20 patients with stable CAD performed 30 min of progressive dynamic (light, moderate, and heavy rating of perceived exertion) and static (10, 15, 20, 25 and 30% of maximal voluntary contraction) upper body exercise in cold (- 15 °C) and neutral (+ 22 °C) environments. Heart rate (HR), blood pressure (BP) and electrocardiographic (ECG) responses were recorded and rate pressure product (RPP) calculated.

RESULTS

Dynamic-graded upper-body exercise in the cold increased HR by 2.3-4.8% (p = 0.002-0.040), MAP by 3.9-5.9% (p = 0.038-0.454) and RPP by 18.1-24.4% (p = 0.002-0.020) when compared to the neutral environment. Static graded upper-body exercise in the cold resulted in higher MAP (6.3-9.1%; p = 0.000-0.014), lower HR (4.1-7.2%; p = 0.009-0.033), but unaltered RPP compared to a neutral environment. Heavy dynamic exercise resulted in ST depression that was not related to temperature. Otherwise, ECG was largely unaltered during exercise in either thermal condition.

CONCLUSIONS

Dynamic- and static-graded upper-body exercise in the cold involves higher cardiovascular strain compared with a neutral environment among patients with stable CAD. However, no marked changes in electric cardiac function were observed. The results support the use of upper-body exercise in the cold in patients with stable CAD.

TRIAL REGISTRATION

Clinical trial registration NCT02855905 August 2016.