Brief periods of NREM sleep do not promote early offline gains but subsequent on-task performance in motor skill learning

•Sleep modulates motor learning.•Brief periods of NREM sleep do not promote early offline gains in motor learning.•Brief periods of NREM sleep improve subsequent on-task performance in motor learning.•Our findings inform the optimization of sleep-wake schedules for motor performance.•Future work is needed to clarify sleep’s impact on training-induced performance gains.•Future work is needed to specify sleep’s impact on detrimental on-task processes.