Dumbbells, Bands and Kettlebells Oh My!

Written by: Cassie Vanderwall, MS RD LDN CPT

The variety of exercise equipment that people find in their local gym, magazines and of course on late night infomercials can make identifying a safe and effective resistance exercise routine an intimidating process.  The best equipment is based on an individual’s exercise experience, balance, strength and range of motion.

Prior to exploring three pieces of resistance exercise equipment: Dumbbells, Resistance Bands and the lesser-known Kettlebells, it is important to explain the basic biomechanics of anaerobic exercise. Biomechanics are principles of how muscles work. There are two basic types of biomechanical systems: static and dynamic. Static mechanics are systems that are in a constant state of motion or no movement at all. Dynamic mechanics are systems that are in motion with changing speeds. Dynamic biomechanics are very similar to the physics of a lever. A lever is a rigid bar that moves around a fulcrum, or axis. The human body (skeletal system) is comparable to the rigid bar that moves around the joints, or the fulcrum. Force supplied by the muscles initiate movement. These movements can occur in one of three planes: sagittal, frontal or transverse.

Dumbbells

Dumbells are one of the most well-known pieces of exercise equipment and are typically utilized for strength-building exercises that also increase muscle size (hypertrophy). When used properly, dumbbells can build muscle mass and strength, while improving posture and stability. Dumbbells work only in the sagittal plane of motion, a static position and rely on leverage. Dumbbells can increase muscle size but often this does not correlate with strength. This is because hypertrophy is often caused by an increase in fluid (sarcoplasm) and not an increase in muscle fibers. Benefits of dumbbells are that they are easy to find and the symmetry of the dumbbell provides a balanced grip. Drawbacks include that it is impossible to use a dumbbell in the transverse plane and most practical movements and injuries occur in this plane of motion. Dumbbells can also be expensive and if not adjustable, individuals may need several pairs to accommodate a variety of exercises and muscle groups.

Resistance Bands

Resistance bands are most often used for prevention and rehabilitative exercises. They are rubber bands that may or may not have handles at the ends. Unlike dumbbells, they allow for more functional movements with greater range of motion. Resistance bands can help to increase strength, endurance and stability in joints. Bands provide for movements in the transverse plane. They are great for beginners, older adults and persons with unstable joints and poor balance. They provide gentler movement than other pieces of equipment. Resistance bands also cost the least amount of money in comparison to the others and are easy to store and very portable. Drawbacks include the fact that judging weight increments to increase resistance can be difficult.

Kettlebells

Kettlebells are an asymmetrical ball-shaped weight with one handle and require a higher level of technical skill for safe use. The movements promote instability and imbalance, which increase the use of core muscles. Kettlebell training is based upon the generation, redirection and deceleration of momentum. They are similar to dumbbells in that they come in different weight increments and differ in that the exercises can occur in a variety of the three planes.  When used correctly, researchers have shown that kettlebell routines utilize a lot more calories due to the incorporation of the nervous, cardiovascular, and skeletal systems in addition to the muscular system. Many women seek muscular strength without size and most experts have noted that kettlebells tend to increase the density of the muscle fibers (myofibrils) without hypertrophy. Unfortunately, kettlebells are not easily portable, can be quite expensive and require several weights to perform a varied routine.

Each of the pieces of equipment benefits a specific population and goal. In summary, my recommendations are as follows. Beginners, older adults and persons preventing and/or rehabbing an injury would greatly benefit from the use of resistance bands. Dumbbells are best for individuals who desire increased strength and muscle size with intermediate exercise knowledge. Kettlebells are ideal for persons with a strong exercise foundation and are looking to take their workouts to the next level.