ABSTRACT
There is a growing body of nutrients and substances purported to enhance exercise performance, however the practicality of what translates to ‘performance enhancement’ is now broader than the simple improvement of an isolated competition or training performance. As discussed in Chapter 3, the goal of sports nutrition is to optimise the adaptations to training, and maintaining an athlete’s capability to train consistently over a period of time provides a platform for this. A dietary supplement may enhance the ability to train consistently in a number of ways. For example, a probiotic (specific bacteria ingested for the purpose of optimising gut microflora)
11.1 Introduction .................................................................................................. 167 11.2 Definition of Dietary Supplements ............................................................... 168 11.3 Potential Benefits of Supplement Use ........................................................... 170
11.3.1 Nutrient Supply in a More Convenient Form (Situation or the Amount) ............................................................................................ 170
11.3.2 Evidence Base Supporting the Use of Dietary Supplements ............ 171 11.3.3 Enhanced Exercise Capacity vs. Performance Improvement ........... 172
11.4 Concerns with Dietary Supplement Use ....................................................... 173 11.4.1 Expense ............................................................................................. 173 11.4.2 The Perception of Superior Nutrition Sources .................................. 173 11.4.3 Negative Health Consequences......................................................... 174 11.4.4 Contamination and Doping Concerns .............................................. 174
11.5 Supplement Use in Paralympic Athletes ...................................................... 176 11.5.1 Practical Considerations for Dietary Supplementation in
Paralympic Athletes .......................................................................... 177 11.5.2 Other Considerations When Using Supplements in Paralympic
Sports ................................................................................................ 182 Key Readings ......................................................................................................... 183 References .............................................................................................................. 184
may be considered ergogenic by reducing the incidence, severity and duration of upper respiratory tract infections (Gleeson et al. 2011; West et al. 2011), thereby allowing the athlete to achieve uninterrupted training. Creatine monohydrate may be considered ergogenic because of its ability to improve training capacity (Maughan et al. 2011) as well as secondary benefits such as enhanced glycogen re-synthesis (van Loon et al. 2004). A formulated sports food such as a carbohydrate gel or formulated protein powder may be considered ergogenic as it can enhance a one-off training performance (Patterson and Gray 2007) and muscle recovery process (Hayes and Cribb 2008), hence optimising the outcome of training in addition to the convenient nutrient source these formulated sports foods provide. It is therefore evident that what traditionally has been held as a definition for performance enhancement needs to be expanded to encompass all areas being identified to contribute to competition performance over acute and chronic time frames. This will also bring clarity to decisions around what constitutes an ergogenic dietary supplement.
