First on the agenda for day 2 at #SSAC was my former colleague and current countryman Peter Blanch, who provided a compelling account that there is no such thing as responders and non-responders, rather, that there are believers and non-believers.
Peter showed a powerful placebo effect with evidence that when subjects in experiments where told they had received performance enhancing supplements such as caffeine, sodium bicarbonate, or even beetroot juice, their performance in a range of timed performance tasks (eg. 1000m running time trial) improved by 1% or more, regardless of whether they actually received the supplement. Likewise, in the same experiments where the subject were told they did not receive the performance enhancing supplement, their performance did not improve, again regardless of whether they actually received the supplement.
His discussion touched on important methodological considerations for designing double blind experiments that test the efficacy of nutritional or therapeutic interventions. He proposed that the expectancy of a positive impact of an intervention participants should always be measured.