Show Posts
This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.
QuoteOMPARISON OF POWER PRODUCTION IN THE HANG CLEAN VS. JUMP SHRUG AT DIFFERENT RELATIVE INTENSITIES
Although the hang power clean (HC) is utilized in many strength-power training programs, it is an exercise that requires high skill. In addition, regular supervision is often required to assure proper lifting technique is being performed. Many variations and lead-up exercises are used to teach the HC. One exercise used to progressively teach the HC is the jump shrug (JS), an exercise similar to the HC but without the catch phase. For individuals training to improve lower-body power for sports other than competitive weightlifting, one can propose to utilize the JS since it is easier to learn, while providing similar lower-body power production and training stimulus as the HC. However, a comparison of these 2 exercises has not been performed in order to make this claim.
PURPOSE: To compare the kinematic and kinetic profiles of the HC and JS at 40, 60 and 80% of one rep max (1RM) of the HC. METHODS: 18 college-age athletes (16 mem, 2 women; age, 21.8 ? 1.9 yrs; height, 178. 1 ? 6.2 cm; weight, 89.0 ? 13.9 kg; 1RM HC, 92.2 ? 15.7 kg) volunteered for the study. All subjects had used the HC regularly in their training for a minimum of 1 yr. On day 1, 1RM HC testing was performed. Within 2-7 days later, motion analysis and force platform testing on the HC and JS was performed at 40, 60, and 80% of HC 1RM. Exercises were performed in a counter balanced order but the relative intensities were always in the order 40, 60, and 80% within each exercise. All testing was completed on a single day. Peak force, peak velocity (center of mass of the body + bar mass), and peak power produced for each lift at each of the relative intensities were compared. Peak joint angular velocities at the ankle, knee, and hip were also compared.
RESULTS: Repeated measures ANOVA revealed that performance measures were significantly higher during the JS compared to the HC for peak force, peak velocity, and peak power. Analysis at the ankle, knee, and hip joints also showed peak joint angular velocities for JS to be significantly higher than HC in all 3 joints. When comparing the relative intensities, peak velocity and peak power were higher at 40 and 60%, than 80% 1RM with no difference between 40 and 60% 1RM. CONCLUSION: Performing the JS at intensities between 40 and 60% 1RM of the HC creates higher loading and joint angular velocities for developing power compared to using the HC at similar intensities.
PRACTICAL APPLICATIONS: The JS is a simple task to master as compared to the HC and is typically a lead-up exercise used to teach the HC. According to our results the use of the JS in weekly programming may create a greater training stimulus for developing overall power than using the HC alone. In addition, teaching or supervising the performance of the HC may be limited by time or ratios of coaches to athletes. When athletes are not training for competitive weightlifting, where the catch of the HC is important to learn, consider performing the JS as part of the explosive training program. Funding for this project was received in a grant from the Graduate Student Research, Service and Education Leadership Grant Program at the University of Wisconsin-La Crosse.
