Practicing a sport such as rhythmic gymnastics from a young age has many advantages. For instance, low-level gymnastic participation at an early age can benefit bone health and balance exercised in rhythmic gymnastics has been shown to improve posture control. However, the age and musculoskeletal development of an athlete should be considered when choosing training schedules and specific movements, a recent study showed. Injuries can occur with young rhythmic gymnasts due to the overloading on foot joints from repetitive movements on tiptoes. Gymnasts as young as 4 years old can specialize within rhythmic gymnastics and thus can experience such injuries while practicing their sport. A research team in Poland evaluated the muscle engagement around the ankle and knee joints during balance exercises of rhythmic gymnastics to assess and explore the cause of these injuries.
The movements in rhythmic gymnastics often require the athlete to balance with one leg on tiptoes in which almost all muscles involved in the stabilization of the motor system joints are activated. This simultaneous activation of antagonistic muscle pairs is known as the coactivation of such muscles.
Two athletes age 8 and 21 participated in the study, allowing researchers to observe the differences in age. The muscle activity and kinematics were assessed during three movements. Two of the movements were performed on tiptoe: the side split with hand support and ring with hand support. The back split with hand support was performed on flat foot.
The lab utilized a BTS SMART system which integrated surface electromyography (sEMG), ground reaction forces and kinematic metrics. sEMG data were acquired through the FREEEMG system from BTS Bioengineering for the knee extensors and flexors as well as the ankle joint extensors and flexors. sEMG data were acquired during maximum voluntary isometric contraction (MVIC) for reference of the dynamic analysis to assess if a muscle was excessively contracting. When muscles activity is significantly higher than the MVIC, the muscle can fatigue and fail to stabilize the joint. The ground reaction forces were acquired with force plates while the movements of the joints were observed and analyzed through a BTS SMART DX system of reflective markers, infrared cameras and analysis software.
Notably, researchers found that the younger athlete demonstrated statistically higher EMG activity than the MVIC in the ankle joint flexor muscles, the gastrocnemius lateralis and gastrocnemius medialis during the ring split. The results of this study indicate that younger athletes can over load the ankle joint and over use their muscles when in this position and similar positions in rhythmic gymnastics. The authors suggest that coaches of rhythmic gymnastics refrain from including the ring split on tiptoe from the training of young athletes to prevent injury. While these positions and movements can earn the athletes top points in competitions, it is well worth it to wait until the musculoskeletal system is developed enough to avoid injury. Furthermore, it is suggested that eliminating the such risky moves from the young athletes’ exercise program may prevent future long-lasting complications. For sports which start athlete at a young age, the age and development of the athlete must be taken into consideration when selecting exercises.
This study exemplifies the power of motion and muscle activity analysis technology to help monitor, asses the movements of athletes, providing key insights which can prevent injury and unnecessary pain for athletes.
This post was based on the following article, cited:
Alicja Rutkowska-Kucharska, Agnieszka Szpala, Sebastian Jaroszczuk, and Małgorzata Sobera, “Muscle Coactivation during Stability Exercises in Rhythmic Gymnastics: A Two-Case Study,” Applied Bionics and Biomechanics, vol. 2018, Article ID 8260402, 8 pages, 2018. https://doi.org/10.1155/2018/8260402.