Mixed

Chronotype significantly modulates sleep duration, social jet lag, and sleep disturbance in shift-workers, with early chronotypes suffering worse outcomes on night shifts and late chronotypes suffering worse outcomes on morning shifts.

If you work rotating shifts, your natural sleep preference (early bird vs. night owl) determines which shifts are hardest on you. Early birds struggle most with night shifts, while night owls struggle most with morning shifts. To minimize sleep loss and jet lag, employers should consider assigning shifts that align with an employee's chronotype, or at least be aware that mismatched shifts will cause significant sleep debt regardless of the employee's effort.