Cycling in Heavy Traffic May Be Bad for Your Heart

Environmental Health Perspectives suggests that the health benefits of cycling may be compromised in high-pollution areas.

The study reports that short-term exposure to heavy vehicle traffic and related pollutants may have a significant impact on cardiac function in healthy adults. The researchers found cyclists exposed to air pollution while cycling showed decreased heart-rate variability for up to three hours after their ride. Heart rates in healthy people should change rapidly in accordance with levels of physical activity. Low heart-rate variability is associated with a higher risk of heart attacks.

The researchers didn’t argue that cyclists would be better off driving, but did recommend avoiding heavy traffic situations whenever possible. The new findings support efforts under way in many cities to create separation between cyclists and vehicles through dedicated bikeways and physical barriers between bicycle and vehicle lanes. According to the report, even a few feet of separation can reduce the impact of vehicle emissions.