Submitted by: Brenda G. Griner, Douglas Boatwright, and Dan Howell
One query that many dancers ask is, “How can I get my jumps greater?” The repetitive execution of demi-plie is used to enhance timing, alignment, power, torso stability, and coordination of joint motion; it’s also a primary element of different actions, reminiscent of pirouette, releve, and all aerial actions (Trepman, Gellman, Micheli, & De Luca, 1998). 4 rules should be utilized when executing jumps of any type. First, any soar should start in demi-plie. Second, as a way to take the soar into the air, the dancer should press off the ground by absolutely pointing the foot. Third, the dancer should land on the balls of the toes, rolling by way of to the heels. Fourth, the soar should finish in demi-plie (Kraines & Pryor, 2001).
Little info is discovered analyzing how dancers use their muscle tissue to carry out extremely skilled actions reminiscent of leaps and jumps. As an alternative, most research give attention to the remedy of accidents sustained by dancers (Trepman et al., 1998). Some accidents, based on Pastime and Hoffmaster (1986), contain “muscle imbalances” ensuing from dance coaching that “locations particular calls for on . . . our bodies” (p. 39). Incorrect coaching can, in different phrases, produce underdeveloped or overdeveloped muscle teams. A examine by Simpson and Kanter (1997) indicated that harm to decrease extremities is frequent amongst dancers pursuing varied types of dance, as an example fashionable dance, jazz dance, and ballet. It linked persistent dance accidents to improper touchdown when leaping.
Lots of the expertise required in dance are additionally utilized in sports activities like determine skating and gymnastics (McQueen, 1986). Sure sport coaching strategies, subsequently, will be helpful to dancers (McQueen, 1986). Fahey (2000) famous that, “Leaping workout routines and plyometrics improve efficiency in strength-speed sports activities as a result of they enhance leg energy and prepare the nervous system to activate massive muscle teams whenever you transfer” (p. 76). Hutchinson and colleagues’ examine of elite gymnasts prompt that leap coaching using a swimming pool in addition to Pilates safely enhanced leaping potential (Hutchinson, Tremain, Christiansen, & Beitzel, 1998). Within the examine, after one month of coaching, gymnasts improved their explosive energy by 220%, their floor response time by 50%, and the peak of their leaps by 16.2%.
The target of plyometrics is to generate the best quantity of pressure within the shortest period of time (Seabourne, 2000). Plyometrics trains the nervous system and metabolic pathways to extend explosiveness, giving the athlete an additional push to maneuver greater and sooner. Plyometrics requires acceleration by way of a whole vary of movement, adopted by rest right into a full stretch. The fast stretch utilized to the muscle by the athlete throughout preliminary push-off is assumed to extend muscle contraction, in flip growing energy. The Cincinnati SportsMedicine and Orthopaedic Heart has developed a plyometrics-based program known as Sportsmetrics, which has been proven to extend soar top and reduce dangerous landings (Hewett & Noyes, 1998). Hewett, Stroupe, and Riccobene (1999) analyzed the results of 6 weeks of Sportsmetrics coaching in feminine athletes, discovering that, after finishing this system, the athletes’ peak touchdown forces decreased by 22%, lateral and medial forces on the knee dropped by 50%, and the peak of jumps elevated 10%. Moreover, hamstring-to-quadriceps power ratio rose from 50% to 66%, creating “a extra favorable situation for the ACL [anterior cruciate ligament]” (Boden, Griffin, & Garrett, 2000, p. 57). Plyometrics coaching has been proven to generate better power output with fewer accidents, and the current examine’s objective was to evaluate the results of a 7-week plyometrics program on the vertical jumps and leaps executed by collegiate dancers.
With approval of the appropriate human subjects review board, a sample of 12 female members of a Division I college dance team participated in a plyometrics training program. The specific program used was the Cincinnati SportsMedicine and Orthopaedic Center’s Sportsmetrics program, in which the dancers participated for 7 weeks. Vertical jumps were measured using a Vertec vertical height measuring device. Strength measurements were made using a CYBEX II isokinetic testing and rehabilitation system and HUMAC software for CYBEX by CSMI.
Initially, a meeting was convened during which the Sportsmetrics program was explained in detail to the 12 participants. They were told that the program would be used 3 times a week for 7 weeks. The program featured approximately 40 min of various jumping exercises. Every week, the amount of time devoted to each exercise increased. The participants kept records of how many repetitions of each they completed. After completing the session, the participants continued with a rehearsal lasting 1–2 hr. Every two weeks, the participants were taught a new program of increased difficulty. The plyometrics program carried the dancers into the beginning of their regular season workouts and game performances.
The 12 participants completed a pretest consisting of a 5-min warm-up and 5-min stretch. Height and weight of each participant were recorded. For each participant a standing reach measurement was also obtained, as the participant stood with feet hip-width apart, eyes forward, and reached vertically, the dominant hand on top of the other hand, using the Vertec vertical height measuring device. Using the Vertec vertical height measuring device, each participant executed a standing two-leg jump; the best of three efforts was recorded.
Using the same device, a two-step leap off of the right leg and a two-step leap off of the left leg were evaluated. Participants stood behind the Vertec and attempted a run, run, leap off of the right leg, with the left leg flexed at the knee and the right hand reaching up. The foot was plantar flexed and placed against the medial side of the knee in passe position. The same leap was executed off of the left leg, with the right leg flexed at the knee.
To obtain strength measurements, the participants were evaluated in a sports medicine laboratory. Each dancer was first of all familiarized with the CYBEX II equipment. Standard protocols for measuring thigh strength with the CYBEX II were used. All posttest measurements were taken after the participants had completed 7 weeks of training. Pre- and posttest data were analyzed using a paired t test, with alpha set at 0.05.
]Outcomes and Dialogue[
There were five freshmen, one sophomore, four juniors, and two seniors on the dance team from which the study participants were drawn. The participants’ biometric data were as follows: age in years, 19.7 + 1.5; height in meters, 1.65 + 0.06; and weight in kilograms, 57.4 + 6.38. In posttests after 7 weeks of plyometrics training, the right quadriceps peak torque at 180 deg/s (M = 57.9 ft lb) was significantly higher than that from the pretest (M = 54.3 ft lb), t (11) = -2.435, p < .05. Furthermore, although the difference was not statistically significant, the change between pretest means for the left quadriceps peak torque at 180 deg/s (M = 54.2 ft lb) and posttest means (M = 57.8 ft lb) did indicate improvement, t (11) = -1.904, p > .05. Vertical jump measures taken after 7 weeks of plyometrics training indicated a significant difference, t (11) = -4.59, p < .05. Also noted was significant improvement in the two-step jump off the right foot, t (11) = -2.5, p < .05. No such improvement was noted for the two-step jump off the left foot, t (11) = -1.05, p > .05.
Thus after 7 weeks of plyometrics training, there were increases in strength in the right leg at 180 deg/s. Strength in the left leg also showed improvement in peak torque performance at 180 deg/s, although not at the level of significance. Significant improvement was seen for the vertical jump and the two-step jump off the right foot.
Most dance teachers teach leaps off of both feet, off the left foot, and off the right foot. However, because many dancers jump off the left foot when executing leaps in classroom combinations at center or in performance, many if not most dancers may exhibit an imbalance in lower limb strength. The 7-week plyometrics program employed in this study may have diminished any imbalance of strength in these dancers.
Further investigation with other dancers is warranted on this topic. It may prove useful to test dancers in middle school, high school, and college. In addition, it may be beneficial not only to take isokinetic strength measures, but a measure of isometric strength as well. The possibility that dance training may develop lower-limb muscle imbalances in dancers should be investigated, as should the usefulness of plyometrics training for younger dancers to prevent any such imbalances.
Boden, B. P., Griffin, L. Y., & Garrett, W. E. (2000). Etiology and prevention of noncontact ACL injury. The Physician and Sportsmedicine, 28(4), 53–50.
Fahey, T. D. (2000). Super fitness for sports, conditioning, and health. Needham Heights, MA: Allyn and Bacon.
Hewett, T. E., & Noyes, F. (1998). Cincinnati Sportsmetrics: A jump training program proven to prevent knee injury [Motion picture]. United States: Cincinnati (Ohio) SportsMedicine Analysis and Schooling Basis.
Hewett, T. E., Stroupe, A. L., & Nance, T. A. (1996). Plyometric coaching in feminine athletes: A potential examine. American Journal of Sports activities Medication, 24(6), 765–773.
Pastime, Okay., & Hoffmaster, L. (1986). In D. Paterson, G. Lapenskie, & A. W. Taylor (eds.), The medical facets of dance. London, Ontario, Canada: Sports activities Dynamics.
Hutchinson, M. R., Tremain, L., Christiansen, J., & Beitzel, J. (1998). Bettering leaping potential in elite rhythmic gymnasts. Medication and Science in Sports activities and Train, 30, 1543–1547.
Kraines, M. G., & Pryor, E. (2001). Leap into jazz: The fundamentals and past for the jazz pupil (4th ed). Mountain View, CA: Mayfield.
McQueen, C. (1986). In D. Paterson, G. Lapenskie, & A. W. Taylor (eds.), The medical facets of dance. London, Ontario, Canada: Sports activities Dynamics.
Seabourne, T. (2000). The facility of plyometrics. American Health, 18, 64–66.
Simpson, Okay. J., & Kanter, L. (1997). Leap distance of dance landings influencing inner joint forces: I. axial forces. Medication and Science in Sports activities and Train, 29, 916–927.
Trepman, E., Gellman, R. E., Micheli, L. J., & De Luca, C. J. (1998). Electromyographic evaluation of grand plie in ballet and fashionable dancers. Medication and Science in Sports activities and Train, 30(12), 1708–1720.
Brenda G. Griner, Division of Well being and Kinesiology and Division of Music, Theater, and Dance, Lamar College; Douglas Boatwright, Division of Well being and Kinesiology, Lamar College; Dan Howell, Division of Well being and Kinesiology, Lamar College, and Beaumont (Texas) Bone and Joint.