Purpose: This study investigated the effects of previous exhaustive upper body exercise on performance and neuromuscular fatigue following a 4-km cycling time-trial (4-km TT). Methods: Eight recreational cyclists performed a 4-km TT with (ARM[subscript PRE]) or without (CONTR) a previous arm-crank maximal incremental test. In each experimental session, neuromuscular fatigue was evaluated with a series of electrically evoked and maximal voluntary isometric contractions (MVC). Oxygen uptake (VO[subscript 2]), heart rate, electromyographic muscle activity (EMG[subscript RMS]) and rating of perceived exertion (RPE) were also recorded throughout the 4-km TT. Results: The average power output during the 4-km TT was reduced (P = 0.027) for the ARM[subscript PRE] (299 ± 59 W) group, compared with CONTR (310 ± 59 W) and overall performance in 4-km TT was impaired (P = 0.021) in ARM[subscript PRE] (382 ± 28 s) compared with CONTR (376 ± 27 s). The decrease observed in MVC (P = 0.033) and potentiated peak twitch force (P = 0.004) at post-TT were similar between the ARM[subscript PRE] and CONTR conditions (P = 0.739 and P = 0.493, respectively). There was no (P = 0.619) change in voluntary activation at post-TT between conditions. VO[subscript 2], EMG[subscript RMS] and RPE measured throughout the 4-km TT were not significantly different between the conditions (P = .558, P = 0.558 and P = 0.940, respectively). The rate of RPE change relative to power output average and heart rate was higher (P = 0.030 and P = 0.013, respectively) in ARM[subscript PRE] (0.031 ± 0.018 AU/W and 168 ± 8 bpm) than CONTR (0.022 ± 0.010 AU/W and 161 ± 7 bpm). Conclusion: These results suggest that impaired performance in ARM[subscript PRE] was mostly due to pronounced perception of effort rather than neuromuscular fatigue.