Background: Consumers are adopting wearable activity trackers to stay healthy and monitor their fitness progress. Purpose: The study investigates the acceptance of WAT by Generation Z users and draws upon achievement goal theory by theorizing how and why consumers use WAT. Methods: Structural equation modeling was employed to analyze intentions to use wearable activity tracker by Generation Z. Further, the study hypothesized relationships of motivational affordances -- self-monitoring, rewards, social comparison on intentions to use WAT, and goal orientations' moderating effect. Results: The SEM results indicated that the structural model had satisfactory levels of fit indices: X[superscript 2]/df = 2.651, CFI = 0.955, GFI = 0.817, NFI = 0.916, TLI = 0.935, AGFI = 0.931 and RMSEA = 0.064. The moderating effect of goal orientations for the intentions to use WAT was significant for some affordances. Discussion: The study suggests Generation Z users show intentions to use WAT. Motivational affordances resulted in intentions to use WAT with moderating effect of some goal orientations impacting the intentions. Translation to Health Education Practice: Self-tracking using wearable technology and personal health management is gaining importance.