Heart rate recovery after exercise and incidence of type 2 diabetes in men

Objectives: We tested that slow heart rate recovery (HRR) after exercise testing, indicative of decreased parasympathetic nervous system activity, is associated with the development of type 2 diabetes in 1,813 healthy men. Methods: Heart rate recovery was calculated as the difference between maximum heart rate during the exercise test and heart rate 1 min after cessation of the exercise test. Results: During an average of 6.4 years of follow-up, 64 (3.5%) subjects developed type 2 diabetes. The unadjusted relative risk (RR) of developing incident diabetes in the slowest versus the fastest HRR quartile was 3.13 (95% CI, 1.28-7.65). However, the association was no longer significant after adjustment for diabetes risk factors and baseline glucose (RR = 2.28, 95% CI, 0.87-5.95). Conclusion: Slow HRR is associated with the development of type 2 diabetes, but these relationships were largely explained by baseline fasting glucose in healthy men.