A dumbbell is a simple tool used in weight training. It is often a single piece of metal or other heavy material that the user holds in their hand. Some nicer models, however, do have variables weights just like a barbell. The dumbbell's weight provides resistance, helping the user to build muscle in the upper body through repeated motions.
The dumbbell has a long history as one of the earliest man-made exercise tools. Some date the dumbbell's use back more than a millennium. Today, dumbbells are still popular in gyms, but in some places, they are being replaced by fixed weight machines, resistance bands, or other newer weight training tools. New tools may have additional benefits over what a dumbbell set can offer for everyday training for athletes or other fitness participants.
The origin of the word "dumb-bell" is a strange one. According to many fitness sources, the first dumbbells were used in Tudor England, where athletes and others used church bells to build muscle. Specific bell shaped tools were fashioned from heavy metals, and made so that they did not make noise when used. These were then referred to as "dumb bells" or bells unable to produce sound.
Although the traditional "dumb bell" tool is just a single piece, some newer types bring innovation to simple exercise routines. Hexagonal dumbbells provide more stability than the traditional round designs, to prevent rolling on a surface. Other types of these tools include customizable design for progressive resistance training, where users gradually add weight in increments for optimal muscle work.
Dumbbells are often used in specific routines that build upper body strength. A similar tool, called a barbell, is two sets of weights attached to a longer bar, so that the user lifts the weight with both hands simultaneously. With dumbbell exercises, the user works with each hand individually, in coordinated exercises that may incorporate speed and resistance elements. Other similar tools include the kettlebell, which has a handle. The kettlebell provides for similar routines, but with an additional "imbalance" element that helps to train core muscles that provide stability for the spinal column and the body in general.
Gyms that include dumbbell sets often help clients to learn how to use them. Some gyms post handy dumbbell training routine activities on the wall near a set of dumbbells. Other offer free initial consultations with a trainer. Visual charts or one on one training can both be good for helping an individual to see how using dumbbells can help achieve the fitness results they want.