We all realise that young children benefit from being outside, but what you might not appreciate is that they value being given free access to play outside whenever they want. Some children are naturally inclined to remain indoors, and they may need encouragement to play outside, but other children would rather be outdoors than indoors.
Try to allow your little ones to play outside whenever they wish. Obviously outdoor play may not fit in with your routine if you don't have a secure garden or they are so young that they need constant supervision, but if you have a safe outside area then encourage your little ones to take themselves outside whenever they wish to.
Besides the fresh air, there are so many reasons why outdoor play is so important. Children playing outside will interact in different ways to when they are inside. They have space to run or move more quickly, they can jump about without fear of being told off for causing danger! They are able to make more noise than when they are indoors, and they will find objects in the garden to play with that help them explore different materials, such as sticks, stones, plants and so on.
Try to offer a freeflow environment where children can choose to go outside whenever they want. Obviously they may not always be able to go out, but giving them an outdoor option will benefit their development in so many different ways.