By Aspasia P. Simeone
(A Speculative Analysis)
It would be difficult to describe Reformer jumpboard jumping to those that are unfamiliar with this activity, without a comparison first to a more common form, say various types of vertical high jumping. Even so, from the perspective of Pilates teachers or students that do participate, it would be informative to explore this subject matter further into the dynamics. Therefore for the unskilled or skilled, knowing ‘what we do’ is just as important as ‘how we do it’. It is my intention to provide a comprehensive yet discernable description for all to grasp, with partiality toward the Pilates jumpboard method.
The most significant difference in free style vertical jumping and horizontal Reformer jumpboard jumping are the effects of gravity and the impact on the musculoskeletal system.
In any free style vertical jumping activity gravitational forces have a direct effect on the takeoff and landing of the jumper with nothing amidst to absorb the final impact upon descent. While short in time and distance this type of motion can be considered free fall at its highest point. Basically all that is involved during the deceleration up-phase motion and the acceleration down-phase motion is a combined effort of the gravitational forces and the power supplied by the jumper to break ground contact. Although there are various other forms of vertical jumping, (running is not included in this analogy. See Example: Vertical High Jump, for other forms) they all have a common characteristic: jumping and landing are performed vertically with respect to the ground. For the purposes of this article, I will be considering the ‘high vertical jump’, where the jumpers’ musculoskeletal system bears the full weight of ground contact. Not so conventional when it comes to Reformer jumpboard jumping…
Various Pilates Jumpboard Positions
The one peculiarity of Reformer jumpboard jumping is the obvious; with Pilates, jumping is performed from a (supine) face-up laying position …or a seated position…or a kneeling position…or a lateral position…or for that matter, one may wonder if it can be done while in a (prone) face-down lying position. If so, then that would imply any anatomical orientation the Reformer can accommodate is suitable for jumpboard. Of course!
Jumping can be executed from a prone position, but who has ever heard of lying face-down on the torso while jumping from the hands? Answer: Anyone that knows Pilates knows this is not unusual because when the jumpboard was introduced into the Pilates repertoire, it was meant to adapt all the planes of movement into a single cardiovascular compilation of major muscle activation. (Perhaps some pictures would be useful here; see Fig.1-Fig.6). In doing so, jumping feet first or hands first is irrelevant since there is never contact with the ground and the movement is relative to the jumpers’ body connection to the Reformer. In all jumping cases, the jumper loses contact with the jumpboard for a time period proportional to the combined spring strength (restorative force) and the external force applied by the jumper. A brief description of spring mechanics will follow shortly to verify this theory.
Fig. 1 Supine Jumping
Fig. 2 Kneeling 1
Fig. 3 Kneeling 2
Fig. 4 Prone
Fig. 5 Lateral
Fig. 6 Seated
Note that during jumpboard intervals the carriage always moves in the direction of the spring tension, whether away or toward the home base. With the force of gravity exerted and pulled toward the ground, gravity is calculated into the combined mass of the moveable carriage and the jumper but does not affect the horizontal motion or the spring resistance. The positive (horizontal) motion of the carriage relies solely on one’s own muscle strength to overpower the spring restorative force and drive the carriage away from the static home position. The forces of gravity have no role in this direction, and as the carriage always moves back and forth with the spring resistance, any variation in anatomical position remains unaffected by gravity. This works during the return spring recoiling phase as well, when the muscles activate to slow the return of the carriage home. Although spring tension strengths are calculated by Hooke’s Law (F=-kX, F:force, -k:spring constant always opposing direction of force F, X:displacement) for spring mechanics, the numerical values in this description are inconsequential. Only the underlying concept is applicable for this nonnumeric assessment. An addendum to this article will further examine the selection of springs for various apparatus, and the method of calculation.
Is Jumpboard Jumping Plyometric?
“Is it plyometric?” one may ask and the answer being twofold; yes and no. As the definition of plyometric is based on explosive muscle contractions in short intervals of time, the choice and/or combination of Reformer tension springs could satisfy those conditions, when the muscle force applied overcomes the stationary static holding force of the carriage. Keep in mind the jumpboard platform acts as the ground and is stationary throughout the interval, while the jumper and carriage move as a single unit. Both closed and open kinetic chain exercises are applicable but not a necessary distinction in this account. More importantly are the lessened effects that rebounding forces have on the participant’s joints and the added benefits gained that constitute this form of aerobic activity.
When the motion is directly in-line to the force of gravity, Plyometric activity works with gravity in the down-phase of the exercise using the eccentric contraction to absorb and store the energy in the muscle for the explosive up-phase concentric contraction. Although the concept is the same on the Reformer, the motion of the carriage is 90 degrees to the ground and therefore gravitational forces are not applied to horizontal motion, as mentioned earlier. Instead the recoil phase of the spring works like the down-phase of the plyometric exercise, absorbing the energy in the muscles and springs for the explosive jump-up-phase cycle. A heavier combination of tension springs will require more power and less time for sequential jump intervals hence will fall into plyometric activity.
You don’t have to be a physicist to understand the dynamics behind the method but some background information will emphasize the great benefits Pilates jumping has when compared to other vertical methods especially on the joints due to the ill effects of compression forces. This is a fact of Newton’s laws of motion coupled with spring mechanics and the conservation of energy (kinetic-motion, potential-stored/static).
Example: Supine Jumpboard
- The carriage is stationary-static at the home base. The jumper is in ready position in direct contact with the jumpboard prepared for first interval:
- The energy stored in the jumpers’ ready muscles and the springs will be released in the first jump. The body is supine, knees bent, pelvis neutral with full foot contact in parallel. The Breathing will be spontaneous during the aerobic activity, and less intentional.
- In a stationary pose, the effects of gravity in this position are proportional to the combined weight of the carriage and the jumper. Gravity forces are not applied in the direction of motion, which is horizontal.
- Jumpboard Jump (plyometric activity optional): From the moment direct contact is broken with the jumpboard and the feet are no longer in connection, the contraction of the muscles have exerted enough force to drive the carriage and extend the springs a proportional distance away relative to the home base. From this vantage point the initial restorative force of the springs has been overcome. The spring force instantaneously pulls back on the carriage in the opposite direction of the displacement once the external jumping force is applied. The carriage motion is totally dependent on the jumper’s activity. Aside from the Breathing which becomes spontaneous during the jumpboard activity, the remaining Pilates Principles; Centering, Concentration, Control, Precision and Flow are employed throughout the interval to ensure proper form and command.
- The most significant aspect is the landing phase or the return to the home position. The timing derivative is directly dependent on the restorative force of the springs and the jumper’s resistance against the recoil. The landing forces are absorbed into the soft jumpboard platform, the recoiling springs and the musculoskeletal system, as the eccentric contraction of the muscles controls the return speed once foot contact is made back on the platform. This affects the timing and setup up for either the next sequential jump interval or halt and jump interval.
- The cardiovascular response can be either aerobic or anaerobic depending on the jump frequency and the spring tension. This can be predetermined by selection but also dependent on jumpers ability.
- In this method as gravity has minimal force effects on the musculoskeletal system, the compression forces on the joints are much less substantial. The stress is absorbed into the other components connected to the jumper; the recoil springs, the cushioned platform, the shoulder blocks etc.
- High Spring Count: In this form of supine jumping, the back body is supported. Since the timing cycle is dependent on the spring strength and the force applied, the higher restorative force will shorten the jumping cycle and allow the back body to remain connected to the moving carriage. Less voluntary effort through the core is required to keep the lumbar and pelvis a neutral holding position. This method permits intense muscle response and stimulates muscle gains and growth.
- Low Spring Count: In this form of jumping, there is more air time as the carriage is propelled away for the base with less effort but more time for the limbs to be unsupported. When the legs are suspended in ungrounded space horizontal to gravity, the deep core must activate voluntarily to secure the lower region of the back body. The hip muscles spontaneously activate to keep the legs energized until jumpboard contact is made again. e. Many variations are available as there is more air time to utilize props and inventive jump routines both unilateral and bilateral. Usage of the upper limbs moving opposite in the direction of the restorative force will lessen the load upon landing. This is enhanced when using small hand weights during jumping cycles.
Example: Vertical High Jump
- The jumper positions themselves in close proximity to the ground in ready position for the first jump.
- Vertical Jump (plyometric activity): It can be deduced that the effect gravity has on the participant regarding compression forces is significant when the motion is in the direct line of the opposing force. To break ground contact and propel vertically in an upward direction, the force exerted by the muscles must exceed the forces due to gravity. This would agree with vertical jumping including but not limited to jumping rope, jogging in place, box jumps, high vertical jumps, squat and jump, burpees, clapping pushups, lunge knee hops etc. where returning to the lowest energy requires the greatest resistance to the gravitational force in the vertical direction. Here the muscle and skeletal systems must absorb the full impact of contact when the feet first (or in some cases the hands) return to the ground.
- The forces of gravity coupled with the jumpers muscle power and mass will control the timing and deceleration in a vertical upward jump. As the direction of motion is subjective, the jump ‘negative is up’ and ‘positive is down’ and is defined relative to the ground forces of gravity for deceleration and acceleration respectively. The gravitational force on the jumper remains unaffected and is directly in line with the motion.
- Not much aside from the musculoskeletal systems to absorb the impact forces when landing on a firm ground.
- The feet, ankle and knee joints bear the initial impact upon ground contact before rebounding if planned. The joints, tendons and ligaments can be subjected to over-use over time.
About the Author
Aspasia P. Simeone is a certified Pilates instructor through the Pilates Institute of America (PIA) as well as a Personal Trainer & Weight Management Consultant through the American Council on Exercise (ACE.) She has an engineering background spanning almost twenty years in the aerospace and telecommunications industry. Her degree in applied physics lends itself to her highly technical and analytical approach to composing kinesiology, exercise, and nutrition documents. Aspasia has maintained an active Pilates and /or fitness business for over 20 years, and designed, created, and copyrighted a comprehensive weight management program called Absolute Fitness & Weight Management which is registered with the Department of State to create caloric deficits through exercise and diet. She currently teaches Pilates at Pilates by the Sea and blogs about Pilates and Fitness on Absolute Fitness Blog.
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