Wearable devices are becoming an important interface between users and fitness activities. Their capabilities are improving exponentially and new strategies are being developed to track sports using sensors that are widely used in robotics. In combination with these wearable gadgets, smartphone applications are normally created to allow the user to visualise data, share data through social networks, or compete with other users. The technology behind these devices is often simple and uses sensors that can be found in a smartphone, such as GPS, accelerometer and gyroscope. However, there are currently no devices capable of measuring the gym activity of weight lifting. In this paper we present WeightBit: a system consisting of technologically enhanced gym gloves, comprised of the sensors previously mentioned, and an additional weight sensor to detect weight and arm movements. Using these data in combination with a smartphone application, it will possible to monitor a new series of sports activities, and specifically weight training. Furthermore, the data collected by the application will enable further research by medical researchers or institutions. The ultimate goal is to keep users focused and keen to live a healthy life, providing them a great tool to track their progress, and also to develop a system that will allow medical institutions access to these data for further study.