It is, unfortunately, a rare event in science to publish unexpected effects of an experiment. Sometimes, results even turn out to be the opposite of what to tried to show with the use of an experimental setting. The learning for the science community, however, is bigger in such cases. Why? A carefully designed experiment (Oliveira et al. 2025) to measure the effects of 2 different 12 month long yoga trainings to prevent falls in 60+ persons (mean age 67) revealed that the less challenging “seated yoga” was better in preventing seniors from falls.
Participants in the more challenging Iyengar yoga-based sessions reported more falls in the 12 months follow-up period. Due to Covid-19 the trainings took place as an online course, which might have reduced the influence of a coach in correcting positions and observe other physiological or psychological issues with participants.
However, the insights are a great lesson for experiments to produce opposite results of expectations with the lesson that human beings can be rather complex. From a health psychology perspective, it might be the case that participants in the more challenging yoga classed became also more daring in balance as well as other exercises.
Just being overly confident compared to their positive improvements, which might turn around an initially positive effect on balance and falls. From a socio-economic perspective, we would question the implicit assumption of the study that participants have a random distribution or underlying tendency towards risky behaviour. The longer the observation window (post-intervention) is, the more intervening socio-economic factors enter into the physiological-behavioural equation. Hence, expect unexpected effects.
