## 1 Introduction  
It has been proposed that athletes set their pacing strategy in an anticipatory manner but continue to make adjustments during exercise so as to achieve their best performances [1]. This self-regulation is hypothesized to be based on information about the exercise, which is then used to prevent severe disturbances to homeostasis and to achieve an optimal performance [2; 3; 4; 5; 6]. Related to this is the concept of teleoanticipation, which states that athletes combine multiple sources of information about the exercise (e.g., endpoint, previous experience, external environmental conditions, energetic reserves, and metabolic conditions) to calculate how much energy they need to finish the exercise without harming the physiological systems and to devise an exercise strategy that will optimize performance [2; 3; 5; 6; 7; 8; 9].  
Studies manipulating the information athletes receive about the exercise they are performing have been conducted to better understand how pacing and performance are regulated [1; 10]. Among the many deception methods, exercise endpoint and time manipulation have been observed to influence physiological responses, performance, and pacing strategy [7; 11; 12; 13; 14; 15; 16; 17; 18]. When false endpoint expectations are given, studies reported that physiological responses, average power, and pacing strategy were similar between trials, while performance (total time) was different [15; 16]. These authors stated that participants selected their pacing strategy based on the perceived distance of a trial rather than the actual distance. Using a similar methodology, one study found that the performance is downregulated when the perceived distance does not meet the actual distance [19], while another study demonstrated that the participants selected their pacing strategy according to their perceived effort [17]. Moreover, when the information about activity is not given during the exercise, the performance was reduced with a slower pacing strategy in comparison with the given information [20]. In contrast, when time was manipulated (modified chronometer) and actual time was slower than expected by the volunteers, participants increased their efforts, affecting both performance and pacing strategy [14; 18].  
Most of the findings in these previous studies are based on exercise in cyclists. Few studies are based on endurance runners [12; 13], and only one study (in cyclists) applied the chronometer manipulation methodology in a closed-loop exercise [18]. Furthermore, physiological differences between running and cycling, together with terrain characteristics and the relationship between exercise duration and strength, may influence pacing differently in those exercise modes [21; 22; 23]. Therefore, it is still not clear how time manipulation, leading to different exercise endpoints, might affect physiological responses, exercise regulation, and performance in runners. To the best of our knowledge, this is the first study to apply chronometer alteration methodology in runners during a closed-loop activity. Given that training sessions are usually a closed loop exercises and time is often the tool use to control exercise duration [24], we believe that this study will contribute to the understanding of the time manipulation exercise responses to improve training models and to achieve the best of the athlete's performance. The aim of this study was to investigate if recreationally active subjects' given incorrect/correct information about the time, leading to different exercise endpoints (54, 60, or 66 min of exercise), would alter their pacing strategy, performance, and physiological responses. We hypothesized that the time information given about the exercise (regardless of the chronometer alterations) might influence the teleoanticipation process and result in similar physiological responses and pacing strategies, but different results for distance completed due to the different endpoints.