Acute Effects Of 24-h Sleep Deprivation On Salivary Cortisol And Testosterone Concentrations And Testosterone To Cortisol Ratio Following Supplementation With Caffeine Or Placebo

International Journal of Exercise Science 10(1): 108-120, 2017. Caffeine has become a popular ergogenic aid amongst athletes and usage to improve athletic performance has been well documented. The effect of caffeine on anabolic and catabolic hormones in a sleep-deprived state has had little investigation to date. The purpose of the current study was to investigate the potential of caffeine to offset the effects, if any, of short-term sleep deprivation and exercise on an athlete’s testosterone and cortisol concentrations via salivary technique. Eleven competitive male athletes volunteered to be part of this prospective double-blinded study. Three test days were scheduled for each athlete; one non-sleep deprived, one sleep-deprived with caffeine supplementation (6 mg.kg-1) and one sleep-deprived with placebo ingestion. Sleep deprivation was defined as 24-h without sleep. Each test day was composed of 2 aerobic components: a modified Hoff test and a Yo-Yo test. Testosterone and cortisol concentrations were measured via salivary analysis at 4 different time-points; T1 to T4, representing baseline, and pre- and post-aerobic components, respectively. Overall no significant differences were detected comparing the different sleep states for testosterone or cortisol concentrations. A trend existed whereby the sleep-deprived with caffeine ingestion state mirrored the non-sleep deprived state for cortisol concentration. Therefore, caffeine supplementation may have potential benefits for athletes during short-term aerobic exercise when sleep-deprived. An increase in mean testosterone concentration post-aerobic exercise was only observed in the sleep-deprived with caffeine ingestion state

Hip abduction pillow use following total hip arthoplasty does not decrease acute hip dislocation rates

BackgroundDislocation following total hip arthroplasty (THA) is a complication with reported incidence rates varying from 0.5% to 10.6%. Placement of an abduction pillow is a precautionary measure undertaken to help prevent acute hip dislocation. Our primary aim is to compare the rates of acute hip dislocation between THA patients who received a post-operative hip abduction pillow and those who did not. Methods This is a retrospective single-center, multi-surgeon case-series of patients who underwent primary THA between June 1, 2014, and June 01, 2018 at our National Orthopaedic Hospital. Exclusion criteria included revision surgery, conversion surgeries. Dislocation rates were compared between the 2 groups: reported as relative risk (RR) estimates.Results 1154 patients  received hip abduction pillows following THA compared to 1296 patients  who did not. 2 patients suffered an acute hip dislocation in the former group compared to one patient in the latter.The relative risk of suffering an acute hip dislocation was 2.25 times higher if the hip abduction pillow was utilized.  Conclusion Removal of the hip abduction pillow following primary total hip arthroplasty does not increase the risk of in-hospital acute hip dislocation, regardless of approach used.

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