Showing papers by "Ben Desbrow published in 2011"

Caffeine withdrawal and high-intensity endurance cycling performance

Abstract: In this study, we investigated the impact of a controlled 4-day caffeine withdrawal period on the effect of an acute caffeine dose on endurance exercise performance. Twelve well-trained and familiarized male cyclists, who were caffeine consumers (from coffee and a range of other sources), were recruited for the study. A double-blind placebo-controlled cross-over design was employed, involving four experimental trials. Participants abstained from dietary caffeine sources for 4 days before the trials and ingested caspulses (one in the morning and one in the afternoon) containing either placebo or caffeine (1.5 mg · kg−1 body weight · day−1). On day 5, capsules containing placebo or caffeine (3 mg · kg−1 body weight) were ingested 90 min before completing a time trial, equivalent to one hour of cycling at 75% peak sustainable power output. Hence the study was designed to incorporate placebo–placebo, placebo–caffeine, caffeine–placebo, and caffeine–caffeine conditions. Performance time was significan...

Exploratory investigation of factors affecting dietetic workforce satisfaction

Abstract: Aim: The purpose of the present study was to explore factors cited by metropolitan dietitians as being critical to their workforce satisfaction in the literature and a previous study. Methods: Twenty dietitians from three metropolitan hospitals in Brisbane, Australia, were recruited by convenience sample to participate in seven focus group sessions. Group discussion transcriptions were thematically analysed by two independent researchers. Results: Participants identified career progression, professional development, resource availability, team and physical environment, reward and recognition as impacting upon their satisfaction. Overwhelmingly, they identified the availability of flexitime arrangements as symbolising workplace flexibility, which was considered the most influential of satisfaction factors. Intangible forms of reward and recognition were also desired and highly valued. Conclusions: Workplace satisfaction among this sample of metropolitan dietitians is multifactorial. Increasing perceived flexibility in work hours may increase satisfaction. Provision of intangible reward and recognition is likely to be well accepted. Future research should involve another survey of a representative sample of practitioners and managers, with the view to developing practical initiatives to improve satisfaction and maintain service delivery.

Caffeine and Physical Performance

Abstract: Dr. Bloomer: Thanks, Jack. In looking at reviews of the literature, concerning both aerobic and anaerobic exercise, as well as some field studies, there is significant evidence that caffeine can provide an ergogenic benefit. However, this is not the case in all studies. Results are mixed and dependent upon many factors including: the sport as well as the type of exercise, whether it be aerobic or anaerobic; rest interval lengths; dosing of caffeine, as well as whether or not it is used alone or in combination with other ingredients such as other stimulants, which are commonly used in the sports nutrition market, or something as simple as carbohydrates.

Development and effectiveness of a placebo beverage similar in sensory properties to an alcoholic beverage

Abstract: Dear Editor, Studies employing a balanced placebo design to examine the effects of alcohol consumption, often report that the non-alcoholic placebo beverage used was credible as an alcoholic drink. In the majority of cases, subjective ratings of beverage sensory properties are used as validation for successful manipulation of the beverage. However, few studies report on participants’ certainty of perception when reporting the success of the placebo manipulation. This letter presents findings from a study examining the effectiveness of a nonalcoholic beverage developed to have similar sensory properties to an alcoholic beverage. It aims to discuss the findings with reference to participants’ certainty of perception. These findings may assist researchers using placebo beverages in future studies, providing some level of confidence in the beverage manipulation used.