A system to monitor hit impact force and to predict the likelihood of a concussion which includes a wearable device with an impact sensor and an application processor for prediction, a smartphone mobile application, a cloud-based data storage system, and an algorithm improvement system. The wearable device is mounted to the players helmet or other locations where the impact force to the head is measured and a prediction algorithm is used to predict the potential risk of concussion. The wearable device wirelessly communicates with a smartphone, where data is viewed and associated information is managed. The impact force data and all related information are also automatically uploaded from the smartphone to a cloud-based database for storage. An algorithm improvement system will periodically analyze the data in order to build a better prediction model between impact force measured and the concussion diagnosed. Once a better prediction algorithm for such model is identified, such algorithm will be sent to the smartphone and hence downloaded to each athletes wearable device automatically for a better prediction of concussion risk.