Training Q & A: Barbells, Dumbbells, and Machines – Which Do I Use In My Workout And Why? – Part 1

By Lee A. Mancini, MD, CSCS, CSN

When I design strength and conditioning programs for my clients, the first few questions that I get are usually along the following theme – “Can I substitute a machine exercise for a barbell exercise or a dumbbell exercise?” “Can I use the leg press machine instead of doing barbell squats?” “Is there a difference between machines and free weight exercises?” “Is there an advantage of one type of exercise equipment over another?”

These are all excellent and intelligent questions and worthy of some good answers. Before I directly address some of these questions, let me give everyone some basic definitions on the equipment that I will be discussing.

Free weights is a broad term encompasses all training equipment that is not a machine, a cable device, or any other piece of equipment where you are not moving the weights directly. Common examples of free weights are dumbbells, barbells, medicine balls, and kettlebells to name a few.

Barbells
Barbells are one of the most easily recognized strength training equipment. They are the long bars that may be anywhere from three to seven or more feet in length. Olympic barbells are traditionally seven feet long and weight 45 pounds. Barbells are usually used for two-handed exercises, gripping the bar with both hands. Some examples of common barbell exercises are barbell squats, barbell deadlifts, barbell bench press, and barbell curls. Weight is added to both ends of the barbell or in some cases the barbell comes with the weight already fixed.

Dumbbells
Dumbbells are short bars usually only eight to twelve inches in length. Most dumbbells are a fixed weight with the majority of the weight at each end, but some dumbbells allow one to add or remove weight. Dumbbells are usually used by placing one dumbbell in each hand. Each hand operates independently of the opposite hand. Even though your right hand may be performing same movement at the same time as your left hand, they are each moving their own dumbbell through space separately.

Medicine Balls
Medicine balls come in all shapes, sizes, and materials. In simplest terms a medicine ball is a ball usually the size of a soccer or basketball that has weight added to it. Some medicine balls are made of materials that make them bounce higher, that make them not bounce at all, that make them waterproof, or that give them some other special quality. Medicine balls can range from weighing one to 100 pounds. Some medicine balls may be as small as a baseball, while others are twice the size of a basketball. Today, there are medicine balls with hand grips attached, with a rope coming out so one can swing them, and a variety of other modifications.

Machine training has a long list of commercial products such as Bow Flex, Nautilus, Universal, Smith, Cybex, and many others. These strength machines use specialized cables, pulleys, bands, and other devices to create tension, provide resistance, and move weight stacks in specific motion. Machine strength equipment really exploded onto the strength and conditioning scene in the 1970s with the start of the fitness craze.

Before we go any further I would like to make two things perfectly clear -

Statement #1 – Doing strength training is better than NOT doing strength training!

Statement #2 – When I design programs for clients of all ages, I use barbells, dumbbells, medicine balls, body weight exercises, and machines. Each piece of equipment has its benefits or drawbacks.

Now, I would like to give you a homework assignment if you choose to accept. The next time you go to your gym or workout facility try this following test. Make sure to use correct form for all the exercises.

Homework Assignment (Read this through twice before you attempt it)

Step #1 – Grab a pair of dumbbells with which you think you could perform NO more than 10-12 repetitions for a single set of flat dumbbell bench press.

Step #2 – Record what weight you are using by adding each dumbbell’s weight together. For example, if you are using a pair of 30 lb. dumbbells, then the total weight is 60 lbs.

Step #3 – Load up a barbell to use for a barbell bench press with an equal amount of weight. Make sure you subtract the weight of the barbell from the total. For example, if the bar weights 45 lbs., and you are trying to make it total 60 lbs then you need to add only fifteen lbs.

Step #4 – Find the Nautilus, universal, or machine flat bench press piece of equipment in your gym. Set the weight at 60 lbs. one final time. Now you are set to begin.

Step #5 – Perform one single set of dumbbell flat bench presses. Try to get as many repetitions as possible until you can not get any more.

Step #6 – Now quickly go to your barbell flat bench. Do NOT rest! Perform as many repetitions as you can of barbell flat bench press.

Step #7 – Without resting go to the flat bench press machine at your gym. Now again perform as many repetitions as possible of the flat machine bench press.

In part two of this series I will discuss your results.

Send any questions or ideas for topics of future interest to questions@DoctorOfFitness.com.

Note:  Lee A. Mancini graduated from Harvard as a two-sport athlete with honors in biology. Board certified in sports medicine and family practice, he works at the Family Health Center and UMass Sports Medicine Center in Worcester . He trains select clients as a certified strength and conditioning specialist and sports nutritionist. If you are interested in hiring him to design an individualized program, click here for our paid consultation services.