Shaking or feeling unstable during a heavy bench press has two main causes: 1) you’re not using your legs to provide stability and 2) your core might be too weak to help stabilize the body during strain. Think about pushing your feet into the floor and driving your knees out throughout the entire press to get your legs involved. For your core, add things like planks and heavy carries to improve the stabilization strength of your core.
Source: Shinkle, J., Nesser, T. W., Demchak, T. J., & McMannus, D. M. (2012). Effect of core strength on the measure of power in the extremities. The Journal of Strength & Conditioning Research, 26(2), 373-380.
From being a mediocre athlete, to professional powerlifter and strength coach, and now to researcher and writer, Charlie combines education and experience in the effort to help Bridge the Gap Between Science and Application. Charlie performs double duty by being the Content Manager for The Muscle PhD as well as the Director of Human Performance at the Applied Science and Performance Institute in Tampa, FL. To appease the nerds, Charlie is a PhD candidate in Human Performance with a master’s degree in Kinesiology and a bachelor’s degree in Exercise Science. For more alphabet soup, Charlie is also a Certified Strength and Conditioning Specialist (CSCS), an ACSM-certified Exercise Physiologist (ACSM-EP), and a USA Weightlifting-certified performance coach (USAW).