- Agonist: Muscles that perform a joint action, including the prime mover and synergists - Prime Mover: The muscle contributing the most force to a joint action when resisted by an external load. - ...

Add Yahoo as a preferred source to see more of our stories on Google. What Are Stabilizer Muscles (and Do You Really Need to Train Them)? - Maridav - Shutterstock You may have heard dumbbell exercises ...

Beth Skwarecki is Lifehacker’s Senior Health Editor, and holds certifications as a personal trainer and weightlifting coach. She has been writing about health for over 10 years. This is going to get ...

You may have heard dumbbell exercises are better than barbell ones because they work more of your “stabilizers,” or that free weights are better than machines for the same reason. But what are ...