The key to increasing physical activity levels is starting with small increases.
Consider your child’s baseline level of physical activity and build up slowly to allow the body time to adapt. For example, if your child’s baseline level is no physical activity, starting with a 10 minute walk in the neighbourhood might be an appropriate place to start.
A conservative approach to increasing physical activity levels and avoiding injuries, especially for an activity like running, is the 10 percent rule. This means progressing time or distance by 10% each week (e.g. if currently doing a maximum walk/run of 5km, aim to progress to 5.5km the following week). You may find you can progress more than this with other activities, like ball games or free swimming.
Most importantly, encourage your child to listen to their body. There is a balance between doing too little, and too much!