Though the myth of the "dumb jock" persists, the truth is that weight training involves many complicated decisions and lots of wise planning. One consideration you'll have to tackle is whether you want to perform multiple muscle exercises or isolated muscle exercises. Though the difference between exercises that focus on one or multiple muscles may seem minor, the distinction can significantly impact your results. Choose one or the other depending on your goals, or choose both -- they each have advantages, so that's a valid workout option, too.
Multiple Muscle Exercises
Multiple muscle exercises, also known as compound exercises, are those in which the movement requires at least two muscles to work together to perform. Such exercises may also be termed multi-joint exercises, as they tend to involve movement across multiple joints. For example, the squat involves movement at the hip and knee joints, with a number of muscles acting upon each joint to drive the motion. Other examples of multiple muscle exercises include the bench press, the deadlift, the squat jump and the lat pulldown. None of those movements could be successfully completed with just one muscle group active.
Isolated Muscle Exercises
Isolated muscle exercises are sometimes referred to simply as isolation exercises or single-joint exercises. These exercises aim to isolate one muscle that provides all of the force needed to perform the movement. Because muscles tend not to cross multiple joints, isolation exercises typically only involve motion at one joint. A great way to tell if you're doing an isolation exercise is to check to see how many joints are moving. If the number is more than one, your form probably needs adjustment. For example, the biceps curl relies on your biceps to promote motion at the elbow joint only -- not the shoulder or wrist. Other examples of isolation exercises include the triceps kickback, calf raises, leg curls and leg extensions.
Benefits of Multiple Muscle Exercises
Multiple muscle exercises tend to be intense -- the squat is definitely not for slackers! -- but the results make the effort worthwhile. These exercises can make your workouts more efficient and allow you to work more muscles in less time. Additionally, the stress of multiple muscle exercises promotes increased release of growth hormone, a muscle-building hormone. If you play sports, you've probably noticed that most movements involve the coordination of multiple muscles, so some of these exercises may also help you improve your sports performance. And when it comes to shedding pounds, multiple muscle exercises are ideal because they burn calories more quickly than isolation exercises.
Benefits of Isolated Muscle Exercises
The fact that multiple muscle exercises are valuable doesn't make isolated muscle exercises useless. In fact, isolation exercises can help you focus on muscles you feel are lagging without tiring out muscles you feel are developing well. Also, isolation exercises can be effective for rehabilitating muscles that were previously immobile due to injury or surgery. If you want to maximize muscle mass and thus don't want to burn too many calories, isolation exercises may be preferable to multiple muscle exercises.
Brian Willett began writing in 2005. He has been published in the "Buffalo News," the "Daytona Times" and "Natural Muscle Magazine." Willett also writes for Bloginity.com and Bodybuilding.com. He is an American Council on Exercise-certified personal trainer and earned a Bachelor of Arts in journalism from the University of North Carolina.