Kinematics of side and cross circles on pommel horse

Abstract

One of the most fundamental skills on the pommel horse is double leg circles (circles). Circles can be performed on all parts of the pommel horse. It was hypothesized that the different sets of physical constraints of the apparatus require a gymnast to adapt circles technique. The purpose of this study was to quantify how gymnasts modify their technique during circles to accommodate different physical obstacles due to different support surfaces and body orientations. To investigate these adaptations, a comparison of the two most common circles on pommel horse Á namely, circles in cross support (crosscircles) and circles in side support (side-circles) Á was carried out. Seven elite male gymnasts performed three sets of 10 cross-circles and side-circles on a pommel horse. Three-dimensional coordinates were acquired using 12 Qualisys ProReflex motion tracking cameras operating at 120 Hz. Temporal characteristics, the motion of the centre of mass, and the body angles Á flexion and lateral flexion Á were analysed. We found that cross-circles took less time to complete a single circle (0.9290.02 vs. 0.9590.02 s), had a smaller ratio for the rear support phase (0.1590.02 vs. 0.1890.03), a narrower supporting-hand distance (0.3390.03 vs. 0.5290.00 m), greater flexion of the body over the rear support phase (449128 vs. 27988), and less lateral flexion of the body over the single-hand support phase (entry: 20958 vs. 35938; exit: 26948 vs. 33948) than side-circles. Our results suggest that gymnasts adapt their technique to the physical constraints imposed by the shape of the pommel horse and the location and orientation of the circles. Cross-circles were characterized by a high rear support position with a narrower hand-spacing, which would require excellent shoulder flexibility and strength. Consequently, lack of these traits may explain the need for greater body flexion in cross-circles than in side-circles during rear support. Understanding the technical differences will facilitate an effective transfer of the technical similarities among different types of circles.

Circles on pommel horse with a suspended aid: Spatio-temporal characteristics

“…The force data were smoothed at 100 Hz using a Butterworth digital filter. For angular computations, two local reference systems were defined using a vector product (Fujihara & Gervais, 2010). In the hip reference system ( Figure 6), the projected angles between the lower trunk (xiphion -the centre of hips) and the thigh (the centre of hips -the centre of knees) on the xz-and on the yzplanes were defined as the lateral-flexion and the flexion of the hip, respectively.…”

“…According to the previous studies, a gymnast completes a single circle on two handles of the pommel horse in approximately 0.90-1.00 seconds (Baudry et al, 2003(Baudry et al, , 2005Fujihara, Fuchimoto, & Gervais, 2009;Fujihara & Gervais, 2010;Karácsony & Č uk, 1998;Salmela & Lavoie, 1977;Yamada, Takamatsu, Yokozawa, Hasumi, & Koyama, 2008). No difference in the total duration for a circle has been found between experts and nonexperts, but experts tend to have shorter doublesupport phases and longer single-support phases comparing to non-experts (Baudry et al, 2003;Fujihara & Fuchimoto, 2006).…”

“…Baudry et al computed the body segment alignment based on the hip joint angle (Baudry, Leroy, & Chollet, 2003Baudry, Leroy, Seifert, & Chollet, 2005;Baudry, Leroy, Thouvarecq, & Choller, 2006). The hip joint angle has also been considered by separating the lateral flexion from the sagittal-plane flexion (Fujihara & Fuchimoto, 2006;Fujihara & Gervais, 2010). Another angular variable related to the amplitude of circles is the shoulder angle formed by the trunk and arms.…”

Kinematic analysis of “Russian” circles in gymnastics

“…However, the main interest of researchers has focused on the most common double leg circles in front and cross support on the pommel horse or gymnastic mushroom, a training aid for pommels so called due to its mushroom-like shape (Fujihara, T., 2006). As Fujihara and Gervais (2010) noted "the different sets of physical constraints of the apparatus require a gymnast to adapt circles technique".…”