Similar cardiovascular and autonomic responses in trained type 1 diabetes mellitus and healthy participants in response to half marathon

Abstract Aims This field experiment examined whether trained people with type 1 diabetes mellitus (T1D) have similar cardiovascular and baroreflex alterations after a 21-km running race when compared to healthy people. Methods Nine T1D (39.0 ± 11.1 yr; 175.0 ± 10.2 cm; 70.8 ± 8.7 kg) were matched with 9 healthy participants (42.4 ± 5.8 yr; 175.7 ± 6.7 cm; 72.1 ± 8.5 kg) who ran an official half-marathon. Before and 1-hour after the race, cardiovascular variables, sympathetic activity (catecholamines), parasympathetic (heart rate variability analysis) modulation and cardiac baroreflex function (transfer function analysis) were assessed during supine rest and a squat stand test (forced blood pressure change). Results Performance time and weight loss [104.0 ± 13.2 and 111.0 ± 18.7 min; −2.57 ± 1.05 kg (−1.88 ± 0.88%) and −2.29 ± 1.15 kg (−1.59 ± 0.59%)] for healthy and T1D participants, respectively) were similar. Before running, no significant differences in any cardiovascular or autonomic variables were noted between the groups. After 1 h of recovery, both groups exhibited post-exercise hypotension, accompanied by increased sympathetic activity, decreased parasympathetic modulation, and reduced cardiac baroreflex sensitivity. Conclusions Our results showed that the pattern of change in cardiovascular and autonomic nervous activity to strenuous exercise are well maintained in T1D participants with a training history of at least 5 years.