Physics of Powerlifting: Bar Force Profile During Deadlift Using Video Analysis and Accelerometers

The deadlift is a popular weightlifting exercise and a common everyday move. Despite this, there are few weightlifting examples in the physics education literature. We calculated the force that the lifter applies to the bar using video analysis and accelerometers, with an inverse dynamics procedure. The presented example is safe, practical, affordable and applicable to any classroom. We compared a one-dimensional to a two-dimensional treatment of the problem, video analysis to accelerometers, and different types of accelerometers. The results are in very good agreement. This allows a variety of approaches and educational opportunities—from a quick demonstration to a small student project. Students have the opportunity to learn about Newton’s second law with non-constant acceleration, inverse dynamics, vector components in different frames of reference, and connections between force, acceleration and velocity in the context of an interesting real-life example.