I found that if my boy doesn't sleep for a nap at least every 3 hours, he will stay awake because of the adrenaline staying awake creates. (babycenter.com)
He stopped breastfeeding to sleep for his nap so I would try in the baby carrier, then when that stopped working I would have to put him in the carrier while vacuuming!! (themilkmeg.com)
If you are feeding, rocking, walking, lying down with your child to get them to go to sleep for their nap then they will need you to do this to help them get back to sleep when they wake at a normal arousal during a nap. (sleeplady.com)