By Ramzy Ross, Ph.D., Cindy M. Gray, Ph.D. and Jason M.R. Gill, Ph.D.
In competitive sport, athletes are constantly seeking novel methods to improve performance and gain an edge on the opposition. The line between what constitutes a legal or illegal ergogenic aid may not be a sharp one, and the prohibited list of substances and methods from the World Anti-Doping Agency (WADA) continues to evolve and be updated. For example, taking human recombinant erythropoietin (r-HuEPO) to improve the oxygen-carrying capacity of the blood is currently banned. However, sleeping in an altitude tent which elicits a similar physiological effect is not banned. Many athletes delve into the ethically grey area of taking supplements which, although not on the prohibited list, claim to produce similar effects to those substances which are banned. Many of these supplements have no clear evidence supporting an ergogenic effect: however, despite such substances potentially being biologically inert, it is possible that the belief of the athlete that such substances are beneficial may improve physiological performance via a placebo effect.
The placebo effect is real and measurable. It is because of this that the placebo controlled trial is the gold standard for medical research. This raises the possibility that some of the benefits of illegal performance enhancing drugs, such as r-HuEPO, may be mediated by a placebo effect.
In our research, reported in the August 2015 issue of MSSE, we sought to quantify the effect of a placebo on running performance, by providing participants with daily injections of saline but fictitiously informing them that they were receiving a drug with similar effects to r-HuEPO. Our randomized crossover study in 15 club-level runners assessed running performance over 3000m in a “‘real world,”’ field-based, head-to-head competition setting on a 200m indoor track. We found a statistically significant 1.2 percent improvement in performance following one week of daily placebo administration. Qualitative analysis of interviews with participants suggests that the placebo improved performance in two ways. First, by reducing the perception of effort and, second, by increasing potential motivation – in other words, the highest amount of effort that the athlete was prepared to exert during the race. We also found a role for cognitive beliefs and expectations in mediating the placebo effect – those who anticipated the greatest positive change from taking the placebo and perceived decreased physical effort during training, had the greatest improvements in performance. Thus, like lucky horseshoes, you need to believe in the effect for it to work.
This magnitude of improvement with placebo, at 1.2 percent, was smaller than the reported effect of r-HuEPO on performance in similar competitive events (~5-6 percent). However, this effect is nevertheless of clear sporting relevance. In the 2012 Olympics, the difference between the gold medal and fourth place was less than one percent in all track events from 1500m to 10000m for both men and women. Thus, this real ergogenic effect of placebo perhaps raises an interesting philosophical and ethical issue. Is a coach who provides his/her athlete with “‘supplements”’ to improve performance facilitating a placebo effect by instilling the belief that ergogenic effects will occur? Moreover, if they do this in the absence of objective evidence that the supplement is beneficial, are they engaging in a morally questionable and deceptive practice or simply following their duty, as coaches, to use all (legal) means possible to get the best out their athlete?
Viewpoints presented on the SMB blog reflect opinions of the authors and do not necessarily reflect positions or policies of ACSM.
|Ramzy Ross, Ph.D.||Cindy M. Gray, Ph.D.||Jason M.R. Gill, Ph.D.|
Ramzy Ross, Ph.D., is an exercise physiology and physical performance specialist currently working with governmental entities of the United Arab Emirates. In addition to physical performance-based research, his roles within the Ministries of Defence, Health and Education involve the health and physical development of youth, enhancement of occupational and military performance, as well as the development of public health initiatives.
Cindy M. Gray, Ph.D., is a Lord Kelvin Adam Smith Fellow in Health Behaviour Change at the University of Glasgow in Scotland. She is a psychologist with a main research focus on using social innovation to engage hard-to-reach groups in physical activity and dietary behaviour change, employing both qualitative and quantitative methods. An example of this is the award-winning Football Fans in Training (FFIT) project, and its follow-up, European Fans in Training (EuroFIT).
Jason M.R. Gill, Ph.D., is a reader (associate professor) in exercise and metabolic health in the Institute of Cardiovascular and Medical Sciences at the University of Glasgow in Scotland. While the majority of his research relates to the effects of exercise and diet in the prevention and management of vascular and metabolic diseases, he also has an interest in sports performance. He has been a member of ACSM for nearly 20 years.
This commentary presents the views of these authors in a research article published in the August 2015 issue of Medicine & Science in Sports & Exercise® (MSSE).