The Influence of the Closed Grip, Hook Grip, and Lifting Straps on Kinetic, Kinematic, and Qualitative Performance Variables of the Power Snatch
MetadataShow full metadata
Weightlifters routinely utilize the hook grip (HG) or may use lifting straps (LS) when performing the various lifts in training. While weightlifting specific movements and their derivatives have been extensively researched and shown to provide beneficial adaptations towards a range of athletes, the influence that different grip-types have on the performance of these lifts is not yet fully elucidated. To date, no investigation has examined what influence the HG or LS has on the kinetic, kinematic, and qualitative performance variables of the power snatch (PS). Thus, the primary purpose of this thesis was to compare the kinetic, kinematic, and qualitative outcomes of the PS with and without the HG and LS compared to a closed grip (CG). It was hypothesized that the HG and LS would increase maximal lifting performance, and enable greater levels of force, and velocity to be generated compared to a standard CG method. It is also hypothesized that the HG and LS would enable an optimized bar-path when compared to the CG condition. Finally, it is hypothesized that participants’ subjective ratings would largely reflect the positive kinetic and kinematic outcomes. Ten resistance-trained (male; n=6, female; n=5) individuals participated in this study. Before the formal testing procedures, a familiarisation took place where each participant completed a 1RM PS with the CG. Each participant then performed three additional 1RM testing sessions whereby the grip-type (HG, CG, or LS) were randomly assigned. A minimum of five and a maximum of ten days separated each standardised testing session. System (lifter + barbell) ground reaction force kinetics were recorded via a force platform, and dual linear position transducer system and bar-path kinematics were ascertained via two-dimensional (2D) motion capture. Each attempt was filmed directly from the side to measure the bar path. Following the 1RM, participants were required to fill out a short questionnaire based around grip security and thumb grip pain. No statistically significant differences were found between 1RM in any conditions between sex (p = 0.13, ηp2 = .40). However, when adjusted for sex, females had a significantly higher 1RM using LS when compared to CG (p = 0.03, ηp2 = .90). Peak force (PF) and barbell velocities were similar between conditions with no significant differences (p = >0.05, ηp2 = .36). Qualitatively, LS provided significantly higher grip security off the floor (p = 0.02, ηp2 = .60), and during the second pull phase of the PS (p = 0.01, ηp2 = .71). Furthermore, the participants also reported feeling more powerful while using LS (p = 0.02, ηp2 = .64), but there were no significant differences in how fast the participant felt catching the barbell (p = 0.06, ηp2 = .51). These findings suggest that females may benefit by using LS when attempting to achieve a higher 1RM with the PS. Furthermore, novice athletes or those that lack confidence during certain phases of a lift may benefit by using LS.