Placebo Effects on the Enjoyment of Physical Activity and Performance among Kindergarten Children: A Randomized Controlled Trial.

Studies with adults and school children have shown that placebos can enhance motivation and performance in physical activities. This study aimed to investigate whether similar effects are present in kindergarten-aged children. A total of 101 children (58 girls, 43 boys) aged 3 to 6 years were randomly assigned to one of two groups that either received a deceptive placebo (DP: "magic potion") or a nondeceptive placebo (NDP: "water") to enhance physical abilities. Each child completed three tasks (sprinting; balancing: standing on a balance board; strength: using a handheld dynamometer) both with and without the placebo. The variables assessed included task performance, enjoyment, and expected and perceived placebo efficacy (measured with nonverbal pictorial rating scales). Results showed that both the DP and NDP increased speed. For strength, balance, and task enjoyment (which was very high), no placebo-induced changes were observed. Expected efficacy was higher for the DP; perceived efficacy did not differ between DP and NDP. In conclusion, reported outcome expectations indicated that kindergarten-aged children were already able to differentiate between the two types of placebos which exhibited positive effects concerning running performance. This encourages further research on using nondeceptive placebos to enhance physical activity, which is crucial for children's overall health.