When preforming testing on Athletes dietary intake should be standardized for all testing to ensure continuity across testing. As from this study and others diet has shown to affect performance. If diet is affecting performance and testing protocol is not standardized results from test to test will not comparable and will result in the prescription of training zones and also the evaluation of performance improvements from test to test.
When testing is undertaken to monitor an athlete’s progress toward competition goals or the effect of an intervention on athletic outcomes, sport scientists should aim to minimize extraneous variables that influence the reliability, sensitivity, or validity of performance measurement. Dietary preparation is known to influence metabolism and exercise performance. Few studies, however, systematically investigate the outcomes of pro- tocols that acutely control or standardize dietary intake in the hours and days before a performance trial. This review discusses the nutrients and dietary components that should be standardized before performance testing and reviews current approaches to achieving this. The replication of habitual diet or dietary practices, using tools such as food diaries or dietary recalls to aid compliance and monitoring, is a common strategy, and the use of education aids to help athletes achieve dietary targets offers a similarly low burden on the researcher. However, examination of dietary intake from real-life examples of these protocols reveals large variability between and within participants. Providing participants with prepackaged diets reduces this variability but can increase the burden on participants, as well as the researcher. Until studies can better quantify the effect of different protocols of dietary standardization on performance testing, sport scientists can only use a crude cost–benefit analysis to choose the protocols they implement. At the least, study reports should provide a more comprehensive description of the dietary-standardization protocols used in the research and the effect of these on the dietary intake of participants during the period of interest.
There are various levels of control or standardization of diet and nutritional preparation before a study or performance test. The unique characteristics of the individual study or test will determine the best approach to standardizing participants’ diet in the days before a performance trial. Researchers need to consider the advantages and disadvantages of each approach and match the level of dietary control required to maximize the findings with the logistics and resources of the study. However, given the potential impact that poor dietary control can have on the outcome of a study, more attention should be given to dietary standardization while planning and implementing the project. In addition, more details should be provided in research publications to describe how dietary standardization was undertaken and how well participants complied with protocols. Finally, measure- ment of the effect of dietary-standardization protocols on the reliability of metabolism and performance of various exercise protocols is an area of research that offers a wide range of possibilities with the potential for valuable insights. The outcomes could help us better understand the effects of nutrition on performance, as well as sharpen our ability to detect small but worthwhile differences in performance from a variety of other interventions.
Full Article: http://journals.humankinetics.com/ijsnem-back-issues/IJSNEMVolume20Issue2April/MethodstoStandardizeDietaryIntakeBeforePerformanceTesting