If you're hitting the gym in an effort to increase upper-body strength, the deltoids are one of the major areas you should be focusing on. Many men and women find using machine exercises to be a simpler and more focused alternative to free weights. Before you commit to an exercise routine to tone your deltoids, you need to find out which machines target them. It's important to train the anterior, lateral and posterior deltoids to prevent muscular imbalances in the shoulder.
Pec Deck Machine
A 2012 study sponsored by the American Council on Exercise set out to determine the most effective chest exercises. Topping the list of mechanical exercises was the pec deck machine, which had a muscle activation score nearly equal to the barbell bench press, the top-performing exercise measured. Defining your chest works hand-in-hand with strengthening your deltoids.
In addition to the pec deck machine, plate-loaded exercises such as the military press, reclined shoulder press, shoulder press and front raise target your anterior deltoids. The anterior deltoid can be seen as a bridge muscle between the chest and shoulders; it's activated most in pushing exercises. If you feel uncomfortable performing a more demanding exercise such as the barbell bench press, use weight machines to take instability out of the equation.
Lateral and Posterior Deltoids
Your lateral and posterior deltoids aren't quite as easy to target as your anterior deltoids, but several machines can help you target these muscles by changing the angle of resistance. For the lateral deltoids, upright rows and lateral raises are simple and effective, while rear delt raises and seated rear delt rows will target the posterior deltoids.
In some experts' minds, mechanical exercises trade true effectiveness and full-body development for ease and comfort. Fitness guru Scott Lardella cites five major disadvantages of using exercise machines: They ignore true mobility and stability; they don't allow you to train in multiple planes of motion; they train isolated movements; they are unnatural training methods for the musculoskeletal system and they do not improve functional strength. If you're concerned about full-body functionality, consider using exercise machines as just one component of a more well-rounded strengthening program.
Steven Kelliher is an experienced sports writer, technical writer, proofreader and editor based out of the Greater Boston Area. His main area of expertise is in combat sports, as he is a lifelong competitor and active voice in the industry. His interviews with some of the sport's biggest names have appeared on large industry sites such as ESPN.com, as well as his own personal blog.