|If it's not cancer, but something as simple as exercise performance believing that a pill will fix it will often suffice to fix it ;-)|
Now, Danilo V. Tolusso, C. and colleagues from the Green State University did not investigate the subtle ways in which ads, sponsored athletes and the price of a supplement enhance its "efficacy", but their study which was designed give us "a more realistic understanding of the placebo effect in a sport or exercise session" is still enlightening with respect to the powers of belief.
Ten healthy, asymptomatic men (age = 22.2 ± 2.4, height = 1.8 ± .01 m, body mass = 81.2 ± 7.4 kg, body fat (%) = 8.1 ± 2.4) volunteered to participate in this no blind (if it was "blind" you could hardly have a good placebo effect ;-) study.
"To be included in this study,subjects must have reported performing sprint training or competition in an intermittent-type sport (e.g., basketball, football, tennis, soccer) at least two days per week. Prior to testing, subjects were instructed to refrain from drinking alcohol 24 hours and caffeine four hours before beginning physical activity. Subjects were also instructed to abstain from intense physical activities 48 hours before testing. Prior to each testing session, subjects were queried regarding adherence to the guidelines set for dietary intake and physical activity.At the beginning of the study, all subjects were provided a brochure upon arrival to the laboratory. In the brochure the scientists claimed that the purpose of the study is to determine the impact of an "FDA approved substance has on performance during multiple sessions of repeated sprint work" (Tolusso.). The brochure contained an overview of previous research regarding the substance that they will be given- obviously one that was very beneficial.
[...] The subjects must not have had a negative bias as to the effectiveness of ergogenic aids, as this may decrease the expectancy of the ergogenic aid to work and result in no placebo response. This was used as a criteria of exclusion to ensure that no subject had a preconceived bias against ergogenic aids (Tolusso. 2015)."
How does "PLACEBO" work? This is how Tolusso et al. explain it: "In brief, the expectancy theory states that any resultant change in performance is largely mediated to the degree that an individual who was administered a treatment (i.e., placebo) believes it to be beneficial. Interestingly, improvements in performance are most commonly associated with the analgesic effect (i.e., pain mediating) that a placebo is known to induce, as research has confirmed that the anterior cingulate cortex, an area of the brain with a high concentration of opioid receptors, is similarly activated during placebo and opioid analgesia trials. This suggests that a placebo may elicit the same neural response associated with decreases in pain sensitivity owing to the binding of opioid receptors. This may yield increases in performance as studies have found that pain sensation can negatively impact performance" (Tolusso. 2015).After the obligatory familiarization trial (obviously the whole study was designed as any good clinical study would be... well, with the exception of the blinding, obviously), the subjects consumed 600 mL of the placebo beverage which contained nothing but distilled water and a commercially available, noncaloric, ‘water enhancer’ (sucralose + acesulfame-K) used to flavor the water. What is interesting is how this was done:
"The first dose of 600 mL was prepared in front of the subjects. Researchers extracted 1 mL of the ‘water enhancer’ from a beaker and extracted it into an Erlenmeyer flask containing approximately 600 mL of distilled water chilled to 10 ̊ C. The other doses of 150 mL were prepared beforehand, with the same concentration as the first dose. Subjects were informed the beverage they were consuming upon arrival and the additional doses of 150mL that they would be consuming during the sprinting trials were the same beverage and that they should expect the same ergogenic benefits listed in the expectancy brochure" (Tolussu. 2015).Immediately after ingestion of this 'powerful ergogenic' *rofl*, the subjects performed a standardized warm-up and three RAST protocols which consisted of 6x35m sprints + 10s active recovery in-between.
|Figure 1: Overview of the study design (modified based on illustration from Tolusso. 2015).|
|Figure 2: Pretty neat performance gains (from Tolusso. 2015) for flavored water, right?|
- Tolusso et al. "The Placebo Effect: Influence on Repeated Intermittent Sprint Performance on Consecutive Days." Journal of Strength and Conditioning Research (2015): Ahead of print.