What is an adjustable free weight?

Powerblock 90LBS
Powerblock dumbbells are a type of exercise equipment that are growing in popularity called adjustable free weights.  If you do any type of home workout circuit video such as P90X or ChaLEAN, adjustable free weights, sometimes called dial dumbbells are much more convenient and less expensive than purchasing a full rack of dumbbells.  One set of Powerblock dumbbells replaces over 1000lbs in traditional free weights.  The way they work is essentially by taking a 50lbs (or 90lbs depending on the model) dumbbell and dividing it up in several slides or slices.  Then, indestructible rods connect the two slides on either side and the rod you insert the pin into determines how many slides are picked up and therefore how much weight.  

Benefits of adjustable dumbbells:

The savings of Powerblock dumbbells over traditional free weights is not the only benefit.  In fact there are many reasons why using adjustable dumbbells is actually more convenient than a full rack:

Space Savings - If you live in a smaller home or apartment, or even if you just don’t have an entire room to dedicate to workout equipment, dial dumbbells save more space than any other exercise investment.  Not only does a traditional dumbbell rack put over 1000lbs of weight on one area of your floor, but they can also take up over 60 inches of space.  One Powerblock dumbbell is 12 inches x 6 inches x 6 inches.  Two together take up exactly one square foot of floorspace, but can easily be slid under a bed, table, or shelf.  

Portability - If you travel often, you know you can’t expect to find decent exercise equipment at hotels or friends homes.  Powerblock dumbbells are extremely easy to transport in the back seat of your car, so you can get a consistent exercise routine no matter what your schedule is like.  

Convenience - Rather than having to go back to the rack in between each workout, using adjustable free weights allows you to stay in the zone and keep plowing through your routine.  If you purchase the Powerblock dumbbell rack, you can avoid damage to your back by changing the weight settings at waist level.  

Benefits of Powerblock Dumbbells:

There are a number of features that set Powerblock dumbbells apart from the competition.  Products like the Iron Master Quick-lock Dumbbells, or the Dial Up Bowflex SelectTech claim to be superior but have several flaws:

Balance - Unlike the Dial Up Bowflex which are rather awkward to use with low weight settings, the Powerblock dumbbell adjusts it’s actual size in relation to its weight.  When you pick up 15lbs with the Powerblock it is much smaller than if you picked up 50lbs.  The Dial Up Bowflex uses the same rod size no matter how much weight you use, so lifting 10lbs still uses all 14 inches of barbell.

Reliability - Although the Dial Up Bowflex SelectTech seems like it may be easier to use, it is in fact quite difficult to change settings as the disks must be perfectly aligned for the dial to spin.  The Powerblocks seem less advanced because they manually use a polymer rod to select the proper weight, but they were specifically designed to be as easy and reliable as possible.

Quiet - Unlike both the Iron Master Quick Lock Dumbbells and the Dial Up Bowflex which can be extremely noisy and annoying to housemates and neighbors, Powerblock Urethane Dumbbells are nearly silent during use and when changing the weights.  

If you have committed to any work out routine that requires the use of free weights, rather than commit to a gym membership, or invest in a full rack of free weights, consider an adjustable dumbbell and start working towards the body you want.