TY - JOUR

T1 - “My Goal Is to Lose 2.923 kg!”—Efficacy of Precise Versus Round Goals for Body Weight Reduction

AU - Frech, Marie Lena

AU - Friese, Malte

AU - Loschelder, David D.

N1 - The research was supported by a grant from the German Research Foundation (DFG LO 2201/2-1) which was awarded to DL and MF. Copyright © 2022 Frech, Friese and Loschelder.

PY - 2022/2/7

Y1 - 2022/2/7

N2 - Overweight individuals often struggle to lose weight. While previous studies established goal setting as an effective strategy for weight loss, little is known about the effects of numeric goal precision. The present research investigated whether and how the precision of weight loss goals—the number of trailing zeros—impacts a goal’s effectiveness. In two preregistered, longitudinal experiments, we contrasted competing predictions as to whether precise (e.g., 2.923 kg) or round (e.g., 3.000 kg) goals are more effective compared to a waiting control condition. In Experiment 1 (N = 121), participants in the two goal conditions lost more weight compared to the control condition—an effect that was mainly driven by precise (rather than round) goals. In Experiment 2 (N = 150), we sought to replicate this effect but found no significant weight loss differences. An individual participant data (IPD) meta-analysis across both experiments revealed that (a) the goal groups jointly lost more weight than the waiting control group and (b) the precise and round goal groups did not differ in weight loss success. An IPD-based multiple mediation analysis showed that healthier eating, but not physical exercise accounted for goal-setting-induced weight loss. We discuss possible explanations for the null findings in Experiment 2 and highlight directions for future research.

AB - Overweight individuals often struggle to lose weight. While previous studies established goal setting as an effective strategy for weight loss, little is known about the effects of numeric goal precision. The present research investigated whether and how the precision of weight loss goals—the number of trailing zeros—impacts a goal’s effectiveness. In two preregistered, longitudinal experiments, we contrasted competing predictions as to whether precise (e.g., 2.923 kg) or round (e.g., 3.000 kg) goals are more effective compared to a waiting control condition. In Experiment 1 (N = 121), participants in the two goal conditions lost more weight compared to the control condition—an effect that was mainly driven by precise (rather than round) goals. In Experiment 2 (N = 150), we sought to replicate this effect but found no significant weight loss differences. An individual participant data (IPD) meta-analysis across both experiments revealed that (a) the goal groups jointly lost more weight than the waiting control group and (b) the precise and round goal groups did not differ in weight loss success. An IPD-based multiple mediation analysis showed that healthier eating, but not physical exercise accounted for goal-setting-induced weight loss. We discuss possible explanations for the null findings in Experiment 2 and highlight directions for future research.

KW - field experiments

KW - goal setting

KW - health

KW - numeric precision

KW - weight loss

KW - Business psychology

UR - http://www.scopus.com/inward/record.url?scp=85125086754&partnerID=8YFLogxK

U2 - 10.3389/fpsyg.2022.793962

DO - 10.3389/fpsyg.2022.793962

M3 - Journal articles

C2 - 35197900

AN - SCOPUS:85125086754

VL - 13

JO - Frontiers in Psychology

JF - Frontiers in Psychology

SN - 1664-1078

M1 - 793962

ER -