The measurable benefits of the barbell are obvious and stand without question. However, the goal of CrossBox training is to perform constantly varied programming over time. Their is no question dumbbells should be included in the mix. Here are the top five benefits to to adding dumbells to your training:
1. Dumbbells can provide the two types of overload that lead to muscle growth: mechanic and metabolic. Mechanic overload is the result of damaged caused by muscle contractions, which stimulates the repair process and leads to an increase in muscle size. Metabolic overload occurs when a muscle is worked to fatigue, which leads to the adaptation of muscle cells being able to store more glycogen which can cause muscles to increase in size. Heavy dumbbells can generate mechanical overload, while moderate-weight dumbbells combined with high reps (to fatigue) can produce metabolic overload.
2. Dumbbell exercises can create both inter- and intramuscular coordination, leading to greater levels of muscle activation. Intermuscular coordination is the ability of a number of different muscles to work together to produce and stabilize joint motion. Intramuscular coordination is the amount of muscle motor units and their attached muscle fibers that are activated within a specific muscle. Using dumbbells for compound, multijoint or multiplanar movement patterns improves coordination between different body segments. Using heavier dumbbells can increase the number of muscle fibers activated within a specific muscle.
3. Dumbbells can benefit both the contractile element and elastic component of muscle tissue. The contractile element is the specific actin-myosin muscle proteins responsible for sliding across one another to create concentric shortening actions or control eccentric lengthening. The elastic component is the fascia and connective tissue that attaches each individual muscle fiber and groups of fibers to one another. The elastic component stores mechanic energy as it is lengthened, which is then released during a rapid muscle-shortening action. Traditional exercises with heavy dumbbells can increase the force production capacity of the contractile element, while multiplanar movement patterns with light dumbbells can enhance the resiliency and strength of the elastic component.
4. Dumbbells can be used for a variety of exercises. The bar is limited in the sense that it will only allow one motion in one specific movement pattern to place load on one muscle or muscle group. Due to their length, standard barbells are best used for compound movements in one specific plane of motion. Due to their size and the fact they can be held in each hand, dumbbells can be used to create a variety of different movement patterns to develop task- or movement-specific strength.
5. Dumbbells allow the user to focus on one arm or leg at a time, which is one way to initiate strength gains by using a heavy overload. A single dumbbell can be used for exercises such as a one-arm overhead press or a split-leg goblet squat to create overload in one limb at a time.