Thermoregulatory and cardiovascular responses to creatine, glycerol and alpha lipoic acid in trained cyclists

To determine whether Cr/Gly-induced thermoregulatory and cardiovascular responses are maintained when the majority (~75%) of the Glu in the Cr/Gly supplement is replaced with the insulintropic agent alpha lipoic acid (Ala).22 healthy endurance trained cyclists were randomly assigned to receive either 20？g/day (4？×？5？g/day) of Cr, 2？g .kg-1 BM per day (4？×？0.5？g .kg-1 BM per day) of Gly and 150？g/day (4？×？37.5？g/day) of Glu or 20？g/day (4？×？5？g/day) of Cr monohydrate, 2？g .kg-1 BM per day (4？×？0.5？g .kg-1 BM per day) of Gly (100？g/day (4？×？25？g/day) of Glu and 1000？mg/day (4？×？250？mg/day) of Ala for 7？days for 7？days. Exercise trials were conducted pre- and post-supplementation and involved 40？min of constant-load cycling exercise at 70% O2 max by a self-paced 16.1？km time trial at 30°C and 70% relative humidity.Median and range values of TBW increased significantly by 2.1 (1.3-3.3) L and 1.8 (0.2-4.6) L in Cr/Gly/Glu and Cr/Gly/Glu/Ala groups respectively (P？=？0.03) and of BM not significantly by 1.8 (0.2-3.0) kg and 1.2 (0.5-2.1) kg in Cr/Gly/Glu and in Cr/Gly/Glu/Ala, respectively (P？=？0.75). During constant load exercise, heart rate (HR) and core temperature (Tcore) were significantly lower post-supplementation: HR was reduced on average by 3.3？±？2.1 beats/min and by 4.8？±？3.3 beats/min (mean ± SD) and Tcore by 0.2？±？0.1 (mean ± SD) in the Cr/Gly/Glu and Cr/Gly/Glu/Ala, respectively The reduction in HR and Tcore was not significantly different between the supplementation groups.In comparison to the established hyper hydrating Cr/Gly/Glu supplement, supplement containing Cr/Gly/Ala and decreased amount of Glu provides equal improvements in thermoregulatory and cardiovascular responses during exercise in the heat.