To evaluate the effects of inspiratory loading on blood flow of resting and exercising limbs in patients with diabetic autonomic neuropathy. Ten diabetic patients without cardiovascular autonomic neuropathy (DM), 10 patients with cardiovascular autonomic neuropathy (DM-CAN) and 10 healthy controls (C) were randomly assigned to inspiratory muscle load of 60% or 2% of maximal inspiratory pressure (PImax) for approximately 5 min, while resting calf blood flow (CBF) and exercising forearm blood flow (FBF) were measured. Reactive hyperemia was also evaluated. From the 20 diabetic patients initially allocated, 6 wore a continuous glucose monitoring system to evaluate the glucose levels during these two sessions (2%, placebo or 60%, inspiratory muscle metaboreflex). Mean age was 58 ± 8 years, and mean HbA1c, 7.8% (62 mmol/mol) (DM and DM-CAN). A PImax of 60% caused reduction of CBF in DM-CAN and DM (P<0.001), but not in C, whereas calf vascular resistance (CVR) increased in DM-CAN and DM (P<0.001), but not in C. The increase in FBF during forearm exercise was blunted during 60% of PImax in DM-CAN and DM, and augmented in C (P<0.001). Glucose levels decreased by 40 ± 18.8% (P<0.001) at 60%, but not at 2%, of PImax. A negative correlation was observed between reactive hyperemia and changes in CVR (Beta coefficient = -0.44, P = 0.034). Inspiratory muscle loading caused an exacerbation of the inspiratory muscle metaboreflex in patients with diabetes, regardless of the presence of neuropathy, but influenced by endothelial dysfunction. High-intensity exercise that recruits the diaphragm can abruptly reduce glucose levels.
IntroductionPost‐exercise heart rate recovery is mediated by the cardiac vagal reactivation. Since vagal control of the heart rate is impaired in athletes at the competition period, we hypothesized that soccer athletes engaged in a competitive season would exhibit an impaired heart rate recovery after exercise.MethodsWe studied 7 male soccer athletes (23 ± 5 years old) and 9 male sedentary individuals (26 ± 1 years old). Heart rate variability at rest was assessed by spectral analysis using the fast Fourier transform. Heart rate was measured at rest, during treadmill exercise test and recovery period.ResultsThe athletes had a lower heart rate at rest than sedentary individuals. Low frequency and high frequency component of the heart rate were similar in the soccer athletes and in the sedentary individuals. During the exercise the athletes had a greater increase in heart rate (114 ± 20 bpm vs. 90 ± 18 bpm, P = 0.02) than in sedentary individuals. Soccer athletes showed a higher maximal oxygen consumption (63 ± 5 ml.kg−1.min−1) than sedentary individuals (47 ± 5 ml.kg−1.min−1; P= 0.001). Heart rate recovery in the first minute after exercise was similar in both groups.ConclusionOur data suggests that high‐intensity exercise performed at the competition season may impair heart rate recovery in soccer athletes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.