Gymnastics is noted for involving highly specialized strength, power, agility and flexibility. Flexibility is perhaps the single greatest discriminator of gymnastics from other sports. The extreme ranges of motion achieved by gymnasts require long periods of training, often occupying more than a decade. Gymnasts also start training at an early age (particularly female gymnasts), and the effect of gymnastics training on these young athletes is poorly understood. One of the concerns of many gymnastics professionals is the training of the spine in hyperextension—the ubiquitous ‘arch’ seen in many gymnastics positions and movements. Training in spine hyperextension usually begins in early childhood through performance of a skill known as a back-bend. Does practising a back-bend and other hyperextension exercises harm young gymnasts? Current information on spine stretching among gymnasts indicates that, within reason, spine stretching does not appear to be an unusual threat to gymnasts’ health. However, the paucity of information demands that further study be undertaken.

The purpose of this study was to examine kinematic and kinetic differences in low and high intensity hand support impact loads during a forward handspring vault. A high-speed video camera (500 Hz) and two portable force platforms (500 Hz) were installed on the surface of the vault table. Two-dimensional analyses were conducted on 24 forward handspring vaults performed by 12 senior level, junior Olympic program female gymnasts (16.9 ±1.4 yr; body height 1.60 ±0.1 m; body mass 56.7 ±7.8 kg). Load intensities at impact with the vault table were classified as low (peak force < 0.8 × body weight) and high (peak force > 0.8 × body weight). These vaults were compared via crucial kinetic and kinematic variables using independent t-tests and Pearson correlations. Statistically significant (p < 0.001) differences were observed in peak force (t(24) = 4.75, ES = 3.37) and time to peak force (t(24) = 2.07, ES = 1.56). Statistically significant relationships between the loading rate and time to peak force were observed for high intensity loads. Peak force, time to peak force, and a shoulder angle at impact were identified as primary variables potentially involved in the determination of large repetitive loading rates on the forward handspring vault.

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BACKGROUND: A small, portable, inexpensive FP is a helpful test instrument in many strength and conditioning settings. OBJECTIVE: The purpose of this study was to assess the reliability and validity of a portable FP. METHODS: The FP was assessed statically for linearity and regionality using known weights and known weight placements across nine regions. Dynamic assessment was conducted by placing the FP on a laboratory-grade one-dimensional FP and performing static jumps, countermovement, and drop jumps with synchronized data acquisition. Frequency response of the FP was assessed by striking the top surface with a hammer. RESULTS: Excellent static linearity (r>0.99), trivial differences in regional forces, excellent correlation between FPs in the static, countermovement, and anchored FP for the drop jump (all r>0.98) were observed. Frequency response from an impact was poor when the FP was not anchored. However, once anchored the FP showed a dominant frequency of more than 10 times the typical jump frequencies and excellent synchrony with the laboratory FP (r>0.98). CONCLUSION: The FP showed good to excellent characteristics in the static and countermovement jumps and the drop jumps when anchored. The primary limitation of the FP is its small size and light weight.

The straight jump is performed by gymnasts of all levels in warm-up routines on the floor and on the beam. Refining this basic skill serves gymnasts when learning high-difficulty jumps. It is common practice for gymnasts to master skills on floor before transferring them onto the beam. The aim of this study was to investigate the kinematic differences of the straight jump on the floor and on the beam performed by county and national level gymnasts. Four county (9±1 y; 133.5±7.6 cm; 29.8±1.9 Kg) and four junior national (13±1 y; 148.5±8.2 cm; 42.8±5.6 Kg) gymnasts volunteered to participate. The straight jump performances were video recorded (80Hz). Simi Motion was used to track nine markers on the gymnast's body. The floor and beam apparatus were instrumented with a pressure mat connected to a digital timer. A 2x2 factorial ANOVA (apparatus x expertise) analysed the following variables: relative angles of shoulder, hip, knee and ankle joints at take-off, peak of the flight and at the minimum vertical displacement of the centre of mass during landing. There was no interaction between apparatus and expertise. There was a main effect of apparatus for shoulder angle at the take-off (fl=132±12°; bm=119±12°), shoulder (fl=154±18°; bm=143±16°) and hip (fl=180±7°; 175±10°) joint angles at the peak of the flight. Expertise showed an effect on the hip joint angle at the take-off (c=164±9°; n= 179±6°) and jump height (c=25.0±7.8 cm; 33.5±4.2 cm). The present study showed that kinematic differences occurred at the instant of take-off between floor and beam and between county and national gymnasts when performing the straight jump, thus some caution should be used in transferring jumping skills from the floor to the beam. Apparatus-specific drills should be used with young gymnast to master these jumping abilities.