Study aim: Although exercise enjoyment is well studied in behavioral context, its associations to aerobic fitness adaptations during exercise interventions have received less attention.

Material and methods: Untrained participants (n = 37, 21 females), cycled either at low intensity (LIT) (n = 18, mean training time 6.7 ± 0.7 h/week) or high intensity (HIT) with 3–7 min working intervals (n = 19, 1.6 ± 0.2 h /week) for 10 weeks. Aerobic capacity, defined as the power associated with maximal oxygen uptake, was the performance outcome. Exercise enjoyment was measured after all exercise sessions during the first and the last week of the intervention.

Results: Exercise enjoyment did not predict the change of aerobic capacity (p = 0.93) and was not associated to the weekly perceived exertion (p > 0.20). Mean (95% CI) enjoyment decreased equally (time × group difference p = 0.98, ηp2 < 0.001 ) in both groups [LIT: −7 (−13–−1); HIT: −7 (−14–0)].

Conclusions: Overall, enjoyment does not seem to be a suitable method to individualize training for improving aerobic capacity. Further, exercise enjoyment decreased during strenuous exercise intervention, and it is not a variable that affects how participants rate their overall weekly perceived exertion.