Self-control is a key determinant of physical endurance (e.g., Bray et al., 2008). According to control theory (Carver & Scheier, 2011), performance feedback influences self-control such that when people underperform (low feedback) they increase effort, while those who overperform (high feedback) withdraw effort. This perspective clashes with self-efficacy theory (Bandura, 1997) which proposes that positive performance increases self-efficacy and performance. The purpose of this study was to investigate the independent and interactive effects of self-control strength depletion (Baumeister, 2014) and feedback on self-efficacy and endurance performance. Participants (N = 78) performed two isometric endurance handgrip trials separated by a congruent (no depletion) or incongruent (depletion) Stroop task and a normative (high/low/no) feedback manipulation regarding their performance on the first handgrip trial. A 2x3 ANOVA of the change in endurance performance from trial 1-2 produced several significant effects. Of primary interest, there was a significant interaction between depletion and feedback (p < .001). In the no depletion conditions, high feedback led to lower self-efficacy and performance while low feedback led to higher self-efficacy and performance. However, the reverse was seen in the self-control depletion groups. The effects of feedback on performance in the control conditions support control theory as well as self-efficacy theory insofar as self-efficacy was positively associated with performance. The results from the depletion conditions suggest performance feedback information is processed differently when self-control resources are compromised. Researchers and practitioners should be considerate of participants' level of self-control depletion when providing performance feedback to manipulate self-efficacy and exercise performance.