A rather intense exercise primarily performed with the use of a single kettlebell weight, the kettlebell figure 8 is a full body compound exercise utilized by newbie gym goers and professional athletes alike so as to induce a significant level of training stimuli in a single convenient exercise.
The kettlebell figure 8 is considered a dynamic movement that oftentimes places significant stress on many of the muscular and connective tissues of the entire body, making it unsuitable for use with certain individuals for much the same reasons that it is an excellent exercise for the rest of the population.
Prior to performing the kettlebell figure 8, it is important to understand the exercise in its entirety, from the benefits to performing it to the exact mechanics behind its somewhat perplexing form.
And as such, the entirety of this article is meant to act as a general informational source for individuals wishing to prescribe or perform the kettlebell figure 8.
The kettlebell figure eight, in its most technical definition, is a unilateral compound exercise primarily performed using explosive strength and a small level of controlled endurance, with an additional cardiovascular effect owing to its dynamic nature.
The kettlebell figure 8, hence its name, primarily uses only a single kettlebell, with the only other requirement being a sufficiently wide enough space for the individual to swing the kettlebell while remaining in a semi-crouched and standing position.
The exact intensity of the kettlebell figure 8 may be tempered through the alteration of certain factors involved during its performance, such as the speed of each repetition, the amount of weight used, and even the volume of sets and repetitions the exerciser undergoes during the course of the workout.
This therefore allows the kettlebell figure 8’s intensity to be increased or decreased according to the needs of the exerciser, giving it a variable difficulty with no particular set point.
To begin performing the kettlebell figure 8, the exerciser will first place their feet in a wide stance, approximately several inches wider than their hips or as wide as is comfortable for their particular biomechanics.
Firmly planting their heels, the exerciser’s legs will then bend at the knees as they simultaneously lean forward at the hips, maintain a straight back and keep their head facing forward so as to protect their spinal column.
The exerciser will then grip a single kettlebell of appropriate weight in their dominant hand with their grip kept in a neutral position in order to prevent any impingement or spraining of the wrist. The kettlebell must not make contact with the floor save for the start and end of the set.
Now in the starting position, the exerciser will put the kettlebell into a controlled swing between their legs by “throwing it” behind the leg opposite their dominant hand, simultaneously reaching out with their non-dominant hand towards the rear of said leg so as to exchange the kettlebell from their dominant hand.
The kettlebell now gripped in the exerciser’s non-dominant hand, they will move the same hand gripping the kettlebell around the leg it was passed behind, forming a circular path around it.
The dominant hand of the exerciser will then move to once again grip the kettlebell as it makes its way around the leg, before once again circling the leg while gripping the kettlebell in their dominant hand – though this time, around the opposite leg.
This completes a single repetition of the kettlebell figure 8 movement, wherein it may be repeated until the set is complete and the exerciser has finished their workout.
Though the kettlebell figure 8 may seem unsafe and rather complicated to individuals that have yet to perform it, this is not entirely true.
With the use of proper form and a reasonable amount of weight, the kettlebell figure 8 can be perfectly safe, with nearly no risk of injury being presented.
The primary two concerns when performing the kettlebell figure 8 in unsafe conditions is the overuse of momentum, which may place unneeded shear force on the many joints involved during the movement, such as the wrists, shoulders and hips.
The second concern is the risk of the exerciser injuring themselves by utilizing too much speed or weight, causing their grip to slip and potentially striking themselves with the heavy kettlebell.
In order to avoid both of these concerns, as previously mentioned, it is best to utilize lower amounts of weight until the exerciser is comfortable and confident in their ability to perform the exercise with proper form.
The kettlebell figure 8 is a wide reaching compound exercise that involves practically every muscle found in the human body.
However, not all of these muscles are trained and activated in the same way, with some simply acting as accessory muscles that provide only a small fraction of the force output needed to perform the exercise, and others being reserved for the sole purpose of stabilizing muscles, preventing injury and hyperextension of the exerciser’s connective tissues.
The term primary mover or agonist refers to the muscle or muscle groups primarily involved in the production of kinetic force behind a movement, such as the entirety of the legs when leaping.
In the exercise of the kettlebell figure 8, the primary movers behind the force produced during its performance are the three gluteus muscles located on the hindquarters, the various smaller muscle groups referred to as the hamstrings, the quadriceps femoris, and the biceps brachii along the upper portion of the arm.
These muscle groups are directly responsible for the majority of the kettlebell figure 8 movement, and as such receive the most of the training stimuli, activation and risk of injury.
Unlike the primary mover muscles, the accessory muscles instead take a far more passive role while the exerciser is performing the kettlebell figure 8, making them less susceptible to injury but also coming with the caveat that they will not receive as much training stimuli or activation.
Therefore, the accessory muscles of the calves, the three heads of the deltoids, and the upper back muscles such as the latissimus dorsi and the trapezius will all receive less significant hypertrophy or strength “gains” by performing the kettlebell figure 8.
The stabilizing muscles on the other hand do not function as accessory muscles at all and are instead utilized during the exercise as a means to protect both the connective tissue and muscle groups themselves from injury via destabilization and overextension.
These muscles used as stabilizers while performing the kettlebell figure 8 are primarily the erector spinae located along the spinal column, the various muscles in the abdomen, the various smaller muscles along the forearms as well as the obliques serratus anterior in certain portions of the movement.
Stabilizing muscles tend to receive less significant training stimuli – if at all, and usually do not accrue significant hypertrophic muscle growth by being used in this particular capacity.
However, some research shows that muscles repeatedly used as stabilizer muscles over long periods of time tend to adapt to the stabilizing function, eventually growing strong enough to stabilize the same volume of weight with less fatigue incurred.
Much like all other forms of resistance exercise, the exact level of difficulty the exerciser may experience while performing the kettlebell figure 8 is directly proportional to precisely how heavy or light the weights in use are.
For experienced exercisers or professional athletes under the supervision or advising of a coach, using significantly heavier weights should present no issue.
In fact, these particular individuals may even benefit from using up to a seven or eight on the rate of perceived exertion scale (RPE), as their bodies are already conditioned to safely being able to function at such a high capacity, allowing more training stimuli to be accrued in a shorter period of time.
However, if the exerciser is new or a returning athlete whose body has yet to fully adapt to intense exercises like the kettlebell figure 8, it is best to reduce the amount of weight being used so as to create a small chance of injury or overexertion.
Owing to the rather complex and explosive nature of the kettlebell figure 8 and its subsequent form, certain mistakes are commonly found during its performance, especially in the case of individuals who are new to the kettlebell figure 8 or simply resistance exercises in general.
The first and most common of these training mistakes is the over tensing and rather awkward movement involved in performing repetitions of the kettlebell figure 8, with jerky and uncoordinated movements serving to increase the exerciser’s risk of injury due to more shear force being placed on the joints.
This may be remedied by simply utilizing a much lower weight and practicing the proper form for the kettlebell figure 8, ingraining the movement pattern in the exerciser’s neurology so they may perform it subconsciously and without effort.
The second of these training mistakes is not only reserved for the kettlebell figure 8 but in most types of resistance exercise, wherein the exerciser will round their back or otherwise avoid bracing their core, taking the stabilizing power of the abdominal muscles and spinal stabilizers out of the exercise.
This can be quite dangerous if repetitively done, especially with the use of higher weight kettlebells, as significant damage to nerves, the abdominal wall, and even the bones themselves can occur due to the unchecked stress of weighted exercise placed along the spinal column and abdomen.
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