Purpose This study examined the effect of pre-exercise low and high glycemic index (GI) carbohydrate (CHO) meals on running performance. Methods Eight endurance-trained male runners completed two trials that were separated by at least seven days in a counterbalanced design. Two hours before the run and after an overnight fast, each subject consumed an isocaloric meal containing either low (GI = 37, LGI) or high (GI = 77, HGI) GI CHO foods that provided 1.5 g CHO(kg -1 body mass in random order. Each trial consisted of a 21km performance run on a level treadmill. The subjects were required to run at 70% VO 2max during the first 5km of the run. They then completed the remaining 16km as fast as possible. Results All of the subjects achieved a faster performance time after the consumption of the LGI meal (LGI vs HGI: 98 7? 2 min vs 101 5?2 min, P

Objective To investigate the clinical characteristics and risk factors of mixed connective tissue disease associated with pulmonary arterial hypertension(MCTD-PAH).Methods Twelve MCTD-PAH patients diagnosed by right heart catheterization(RHC)at Tianjin Medical University General Hospital were retrospectively included,and 36 MCTD patients without pulmonary arterial hypertension(MCTD-non-PAH)were randomly selected from the same period of hospitalization based on gender and age.The clinical features and auxiliary examination of the two groups were compared,and the survival status of the two groups was compared.Results The proportion of dyspnea after activity,myositis and pericardial effusion were higher in the MCTD-PAH group than those of the control group.Serum sedimentation rate and immunoglobulin G(IgG)levels were higher in the MCTD-PAH group.Multivariate Logistic regression analysis showed that dyspnea after activity and high level of IgG were risk factors for predicting the occurrence of PAH in MCTD.Three patients(16.7%)died in the MCTD-PAH group,and no patients died in the control group.Conclusion Pulmonary arterial hypertension is one of the serious complications of MCTD.MCTD patients have shortness of breath after activity and high level of IgG should be wary of concomitant PAH.