Adjustable Dumbells

If you look around today at sporting goods stores or surf some fitness websites, you’re going to see a lot of modern adjustable dumbells that have different types of locking mechanisms to add and remove plates.  These mechanisms do not require that you actually take a plate off, rather, you simple select the weight you desire and lift.  The plates come with it.

Contrast that with our friends to the left here, which although are still a new set of adjustable dumbells, are very old technology.  Old, inconvenient, and cumbersome.

If we look at their construction, it’s quite basic.  Two bars that are threaded on each side to accept a collar.  This collar screws onto the bar and compresses the plates against a shoulder that rests just outside the grips.  You can add just about any amount and configuration of plates that will fit on each side of the grip.  It’s so simple it’s almost genius.  But not quite.

The problem comes when you want to change weights.  Don’t get me wrong, the whole contraption is very secure and safe.  There’s probably no safer way to secure weights to a bar.  The problem comes when you want to shuffle weights.  Adding plates onto the outside is relatively simple, as long as you don’t mind having them stacked randomly.  those of you who are OCD and demand that your largest plates be on the inside will soon find this to be an unacceptable situation, and start removing smaller plates before you put on the larger ones.  This takes time, and is tedious.

When taking plates off, you can’t simply strip off the 5 lb plate on each side if there’s a smaller one closer to the collars.  You’ll need to take the smaller weights off the adjustable dumbell, remove the larger one, then add the smaller plate back on before tightening the collars.  Again, messy.

Working out is enough of a hassle that I like to minimize as many interruptions as possible to get maximum return on my time invested.  I think most people will agree.

Adjustable dumbells are great. They have many advantages over bar and plate weights and weight machines, and can really fit well into a small area of your home or gym. On top of their size advantage, they do a much better job isolating all your peripheral and supporting muscles during an exercise than solid-bar lifting does, and a much better job than weight machines in general. The reason for this is pretty simple, but let’s start with the shortcomings of solid-bars and machines

Looking at weight machines, you’re basically lifting a weight attached to a hinge. That means that the arm the hinge is attached to can only follow a set arc, and will not take any effort to keep from deviating left or right, front or back. All you have to do is push the weigh up and down, and this movement only strengthens very specific muscle groups, depending on which exercise you’re doing. Not so with adjustable dumbells.

If we take a look at solid-bar weights, we’re eliminating one of the supports, but the other still exists in some form or another. That is, free weights can fall forward or backward if you don’t stabilize them where on a machine they cannot. Too, they require some effort to keep from falling side to side, but not as much since the bar is linked and your arms are working together in the effort to stabilize. So the conclusion is that solid-bar free weights are better than machines, which are better than nothing.

Now let’s analyze adjustable dumbells. You have two independent weights that your arms must not only push up, but also keep from falling out, in, back, forth, and every other direction. And they must do this with no stabilization from the other side. So, with a solid-bar setup if the bar is moving to the left with a 2 Nm force, each arm really only has to contribute half of that to stabilize it. With a separate weight in each hand, the arm with the weight in motion will have to correct the movement by itself. This makes both arms stronger.