“Which is most effective to gain mass in my arms – the rod, the barbell, or the curly?”  This question was posted on Quora.com recently.  While there are many exercise and fitness questions that I choose to skip over, I decided to answer this one because I felt it highlighted a common misunderstanding in the fitness industry.  There is a notion out there that the results you get from exercise are somehow dependent on the tool (machine, free weight, cable, band, etc.) that is used while exercising.  And, if you use one tool versus another, that you will get better results (more muscle, less fat, increased strength, improved endurance, and so forth).

Here’s the thing, though — the tool that is used is not the sole reason that specific results are attained.  The things that get you results are how appropriately the 1) tool and 2) conditions of the exercise challenge the principles of the mechanical, physiological, neurological, and biochemical systems within your body.

Let me explain.

Different tools, let’s say a barbell versus a dumbbell, provide different mechanical opportunities to challenge your body.  Some opportunities may be more mechanically “ideal” based on your injury history, your current joint motion capabilities, and the type of challenge you are wanting to create for yourself.  However, if the opportunity is not maximized through the exercise conditions that are created, such as the amount of time the exercise is done for (reps & sets), the intensity of the exercise (how great the challenge is), and where your focus is while performing the exercise (moving the weight vs. squeezing the muscle), the physiologic adaptations that you are hoping to glean will be much more difficult to come by.

Related: Doing The “Right Things” When You Exercise

With this in mind, here is how I answered this Quora question:

“It is not so much about the tool as it is how you are using the tool. In other words, your arms aren’t going to grow more simply because you are using a barbell vs. a dumbbell. But, your arms will grow more because of how you use the barbell or the dumbbell.

Specifically, your arms will grow relative to the amount of (appropriate) stress you challenge them with. There are actually 4 conditions that need to be present when you do an exercise in order for muscle tissue to maximally grow. First, you need to have a time under tension of at least 43 seconds, i.e. your set needs to last at least 43 seconds. Second, you need to be doing the exercise to momentary muscle failure, i.e. at the end of the set you should not be able to complete another rep. Third, you need to be directly challenging the tissue you are wanting to grow, i.e. if you want your biceps to hypertrophy, you need to be doing exercises that challenge your biceps, not doing squats. Fourth, you need to focus on squeezing the muscle you are trying to challenge while you are doing the exercise, not on moving the weight. In the biceps example, focus on squeezing your biceps while performing a curl instead of thinking about performing the rep itself.

Points number 1, 2, and 4 above are designed to maximally speed up the signal transduction pathways within the tissue you are trying to have grow. Point number 3 is often a myth-buster of sorts as it is common fitness practice to tell clients they have to lift legs in order to get a bigger upper body. This is complete nonsense, however.

At the end of the day, it does not matter whether you use a barbell or dumbbell from the standpoint of trying to get your arm muscles to hypertrophy. There are various mechanical considerations with each, but that falls outside the scope of this question. In order to give your arms the best chance to grow, you will have to do your sets for at least 43 seconds, do them with a light enough weight that you are not failing before that time, but challenging enough that you eventually work to failure, do exercises that directly challenge your arms, and focus on squeezing the muscles you are wanting to grow while you are doing the exercise.

If you are interested in reading more about these concepts, check out my blog on the topic here (references included).”

Related: Building Muscle: Four Exercise Necessities

How does this apply to you as a consumer and/or doer of exercise?  Basically, don’t get caught up in the hype that a specific exercise product will absolutely lead to you getting the results you want.  Whether it is an awesome-looking treadmill/stair climber combo, a sexy new abs machine, or a fantastic butt blaster, all of these machines are simply providing an opportunity for you to challenge your body.  While the mechanical considerations for each machine and tool are certainly important, at the end of the day, if you are not using the tool in a manner that appropriately challenges your physiology, you are unlikely to get the results you are wanting.

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Charlie Cates

Charlie Cates is the leading consultant to high-level professional, college, & high school basketball players in the Chicagoland area for injury prevention, recovery, & muscle performance. As a certified Muscle Activation Techniques® MATRx practitioner & former college basketball player, he uses his personal experience & understanding of the game & player demands to create customized exercise options for his clients to recover faster & perform their best. He is certified in the highest levels of MAT®, including MATRx, MATRx Stim, and MAT® Athlete. Follow him on Instagram @CharlieCates!