Effects of beverages with variable nutrients on rehydration and cognitive function.

The purpose of the present study was to investigate the effect of carbohydrate-electrolyte solution (CE), lemon tea (LT), and distilled water (DW) on rehydration and cognitive performance after 60 min of moderate exercise. 9 healthy males and 10 eumenorrheic females completed 3 runs in a randomized crossover study design. During the 4-h recovery (REC) period, they consumed either a volume of CE, LT or DW equal to 150% of their body mass (BM) loss during the previous run. The 3 beverages vary in carbohydrate and electrolyte content. A battery of cognitive tests was performed upon arrival, immediately after exercise, and at the end of REC. After the REC, the restoration of BM loss was lower in the DW and LT trials than that in the CE trial in the female participants (CE vs. LT vs. DW: 59.3±2.8 vs. 41.7±5.7 vs. 45.6±2.2%). When compared with the DW, the accuracy of performances during a working memory task in both males and females was higher in the CE and LT trials. The results suggested that during a short-term recovery, both LT and CE show certain beneficial effect in maintaining cognitive performance. However, CE appears to be more effective than LT and DW in rehydrating female participants.

Effects of a hot environment on simulated cycling and running performance in triathletes.

AIM: This study examined the effects of a hot environment on metabolic responses, thermoregulation, and performance during simulated cycling and running in triathletes. METHODS: Seven male triathletes completed two trials in moderate (22+/-0.2 degrees C, 76+/-2% relative humidity, M) and hot (31.2+/-0.2 degrees C, 76.4+/-1.6% relative humidity, H) environmental conditions separated by at least 7 days. The subjects were required to complete a self-paced 40 km simulated cycling, followed by a 10 km run on a treadmill for as fast as possible in both trials. RESULTS: The overall performance time was faster in M than H (M vs H, 119+/-6 min vs 127+/-6 min, P<0.01). Moreover, there were no differences in the cycling time between the two trials, but the run time was faster in M (M vs H, 51+/-4 min vs 59+/-5 min, P<0.05) than in H. Ad libitum water consumption was higher in H than in M (H vs M, 970+/-231 mL min(-1) vs 547+/-131 mL min(-1) P<0.05), and the mean skin temperature was also higher in H than in M throughout the exercise (H vs M, 35.3+/-0.1 vs 33.3+/-0.1 degrees C, P<0.05). However, there were no differences in rectal temperature, blood lactate, blood glucose, body mass change, plasma volume change, osmolality, carbohydrate oxidation, and fat oxidation between the trials. CONCLUSION: The results suggested that triathletes reduced their running performance after a 40 km simulated cycling when the ambient temperature was high.

Effect of CHO loading patterns on running performance.

This study examined the influence of 3-day isoenergetic carbohydrate (CHO) loading with different glycemic index (GI) and glycemic load (GL) meals on running performance and metabolic responses. With a randomized crossover design, nine male runners performed a 1-h run at 70% VO2max followed by a 10-km performance run after a 3-day diet adaptation, which involved different GI and GL meals [CHO intake (%), GI, and GL per day were 73%, 80, and 553 for the high GI and high GL (HH); 73%, 36, and 249 for the low GI and low GL (LL); and 31%, 79, and 227 for the high GI and low GL (HL), respectively]. There were no differences in the time to complete the 10-km run between the two high-CHO trials; however, the performance in the LL trial was improved as compared to that in the HL trial (mean +/- SEM: HH vs. LL vs. HL: 51.3 +/- 5.3 vs. 48.6 +/- 1.3 vs. 55.3 +/- 6.9 min). It appears that the amount, rather than the nature, of the CHO consumed during the 3-day isoenergetic CHO loading may be the most overriding factor on subsequent metabolism and endurance run performance.

The application of clinical simulation in crisis management training.

Since it was first introduced more than 30 years ago, clinical simulation has become a popular tool for medical training, particularly in crisis management. The modern high-fidelity patient simulator consists of a whole-body mannequin with integrated electronic patient monitoring; it is controlled by computers capable of simulating numerous clinical scenarios and patient characteristics, and reacting to various interventions appropriately. Simulator training is theoretically superior to conventional training in management of rare crisis situations, as it allows unlimited practice in a safe yet familiar environment. Training in clinical skills can be developed, together with competency in crisis management behaviours such as leadership and communication skills. Although there is evidence demonstrating the popularity, reliability, and validity of simulator training, its superiority over conventional training has not been proven, and research in this area is required.