Gradually increase the time spent on his tummy as he comes to love this special time with you. (confessionsofadrmom.com)
Play therapy increases social communication and improves language development by increasing time spent in enjoyable interactive play. (playconnectgrow.org)
Keep in mind that there is definitely a point of diminishing returns with increasing time under tension, but it is a way to progress. (mollygalbraith.com)