Author: Ella Ward, date published: 28/10/13
The problem of using placebo’s in sport arises when a coach’s desire to improve performance involves deception and compromises the coach-athlete relationship. A solution would be to demonstrate a placebos efficacy without deception (Benedetti et al., 2011). Recently, a study by Friedlander et al. (2010) supported the solution, concluding open-label placebos improved the symptoms in patients with Irritable Bowel Syndrome (IBS). Conversely, a study by Fitzpatrick et al. (2007) reported a decline in force production after disclosing the nature of the placebo intervention. Contrary to these two studies, the solution is sparsely investigated in the literature. Thus, a research proposal will be constructed to investigate a placebo intervention without deception. This will also provide coaches and sports scientists with a framework to optimise a placebo effect without deception.
The purpose of the proposed study is to determine whether Kinesio-tape improves circulation in the gastrocnemius muscle during cycling. The study design will be within-group. This is an improvement to Friedlander’s between-group design, where participants assigned no treatment may have been disappointed. This may have negatively influenced the results (Kaptchuk et al., 2011). Furthermore, the study will be unblinded. This is integral to its validity because it needs to reflect the circumstances where both the coach and athlete are agreeable to the placebo. However, unblinded studies have associated risks of bias (Chen et al., 2011; Kaptchuk et al., 2011).
For example, participants may change their behaviour during experimental research. This change is known as the Hawthorne Effect (Campbell et al., 2009; Rowland, 1994). Despite being difficult to overcome in a laboratory environment, measures will be taken to prevent this. For example, the cycle ergometer wattage and revolutions per minute would be maintained at constant values throughout the testing to prevent participants exercising at a higher work rate.
Another limitation is response bias, which occurs through self-reporting methods (Kaptchuk et al., 2011). An example of this occurs when participant’s who are overweight tend to over-estimate duration and intensity of exercise to “please” the experimenters (Acra et al., 1999). This bias was a limitation of Friedlander’s study because only subjective measures were collected. This inhibited researchers from discriminating between response bias or the placebo physiologically improving the condition (Kaptchuk et al., 2010). Therefore, this study will collect objective measures (Kaptchuk et al., 2011). For example, circulation will be measured by exercise physiologists using a non-invasive Laser Doppler. This method has been used in previous studies investigating KT and circulation (Docherty et al., 2012; Hashimoto & Kase, 1998). Differences between responders and non-responders will be investigated by sports psychologists. This would consist of a pre-participation questionnaire, examining the individual’s expectations, beliefs and personality traits such as Five Factor Model (McCrae & John, 1992). Each participants subjective results would be compared to their objective results.
Lastly, an unblinded study may heighten a placebo effect through the expectancy effect (Kaptchuk et al., 2011). Expectancy plays an important role in the efficacy of placebos (Benedetti et al., 2005). Friedlander’s study contained this bias due to its persuasive debriefing, which inadvertently communicated to the participants the expected results (Campbell et al., 2009; Kaptchuk et al., 2010). It is important to note that discussion of the pros and cons of treatment and shared decision making is an integral component in the coach-athlete relationship (Miller et al., 2012). Therefore, the debriefing rationale will not induce expectation, but will present multiple findings from clinical studies. For example: “one study concluded KT did not affect circulation, however another study concluded KT improved circulation when combined with low-strength exercises” (Docherty et al., 2012; Hashimoto & Kase, 1998).
The results from this study would further advance the knowledge in this field. It would also have the potential to improve performance and provide an alternate route for coaches to pursue which does not compromise the coach-athlete relationship. However overall, there is no empirical evidence supporting the efficacy of placebo’s without deception (Fitzpatrick et al., 2007). Thus, the solution would require large amounts of clinical research to match the literature that has been previously published on placebos, which may be unrealistic. The solution may also have implications to previous research, which may become invalid and meaningless when compared to overt placebo trials. The question still exists that if the research yields significant findings, will sports scientists and coaches use the results? Or will the traditional method of deception still be used due to its simplistic nature?
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