Magnesium Carbonate as Placebo?

This study from 2016 brings up an interesting observation wrt. chalk use among climbers. Even though there is no measurable “material” difference (e.g., coefficient of friction) between “chalk” and “no chalk” use, climbers were performing measurably better with chalk than without. This suggests that either our measurements are wrong or a strong “placebo” / psychological effect is at play here. Is chalk all in our mind? This post is part of a series where we highlight the existing research around chalk.

Abstract, Emphasis ours: Rock climbers believe chalk dries the hands of sweat and improves the static coefficient of friction between the hands and the surface of the rock. The purpose of this study was to assess whether chalk affects geometric entropy or muscular activity during rock climbing. Nineteen experienced recreational rock climbers (13 males, 6 females; 173.5 ± 7.0 cm; 67.5 ± 3.4 kg) completed 2 climbing trails with and without chalk. The body position of the climber and muscular activity of the finger flexors was recorded throughout the trial. Following the movement sequence participants hung from a standard climbing hold until they slipped from the climbing structure, while the coefficient of friction and the ratio of the vertical forces on the hands and feet were determined. Although there were no differences in the coefficient of friction (P = .748), geometric entropy (P = .359), the ratio of the vertical forces between the hands and feet (P = .570), or muscular activity (P = .968), participants were able to hang longer after the use of chalk 62.9 ± 36.7 s and 49.3 ± 25.2 s (P = .046). This is advantageous because it may allow for prolonged rests, and more time to plan the next series of climbing moves.

PubMed Link Photo by Brook Anderson