Mean (◾) effect size (95%CI), overall composite effect size (—), 95%CI of overall composite effect size (- ·—· -) for magnitude of difference between predicted 1RM by two-point method and 1RM value by direct method.

A: linear position transducers (LPT); B: camera-based optoelectronic device (CBOD); C: inertial measurement units (IMU); D: smartphone application (APP). It should be noted that the smaller the ES, the more accurate the two-point method predicts 1RM.