Similarities in jumping and weightlifting performance Exercise Science Faculty Sponsor: Dr. Chris Bailey INTRODUCTION Athletes make sharp, quick movements when performing in their sport. According to Hernandez- Davo and Sabido, sports movements happen faster than human muscles take to reach maximum force production. Therefore, coaches look to increase rate of force development within their team/athlete because they will be more likely to perform at a higher level. The higher this rate is, the faster an athlete would be able to sprint or the higher that athlete would be able to jump. As a result, coaches may like to train heavy to increase an athlete s or team s rate of force development. Carlock, Smith, Sands, Hartman, and Stone all looked at the relationship between vertical jump, counter movement jump and squat jump, power estimates and weightlifting ability. The purpose of their study was to assess the usefulness of the vertical jump power as a field test for weight lifting. They used 64 national level weight lifters, men and women, in their study. They measured vertical jump using the Kinematic Measurement System which utilized a switch mat. Pearson s correlations showed that the vertical jump was strongly related with weightlifting ability and therefore, peak power derived from the vertical jump is a great tool in assessing weight lifting performance (Carlock). Durovic, Zrnzevic, Okicic, Jorgic, and Milanov did another study to determine the relationship between muscle contractile potential of leg extensor muscles and starting performance. They also used Pearson s correlations to evaluate the relationship between squat jumps and how fast a 10-meter swim was. Their participants included 27 male competitive swimmers. The results showed that if a swimmer had a higher maximal force value, that swimmer would be able to finish their 10-meter swim faster than those with lower force values. There was also a very strong correlation between peak power of the squat jump and how fast the swimmer swam the 10 meters (Durovic). This study shows again that the correlation between weightlifting movements and jumping is usually positively correlated. An increase in rate of force development can be achieved by long term resistance training, training with heavier loads, and even speeding up how fast a person s bar speed is. To the current author s knowledge, the relationship between force-time curves of jumping and specific weightlifting performances have been tested. Therefore, the purpose of this study is to evaluate the correlation between jumping and weight lifting in terms of force production. 1
METHODS The participants of this study were 11 Lagrange College weightlifters or experienced lifters in some way. All participants of this study signed and read an informed consent document. Before starting the activity, participants started with a full body dynamic warm-up. This warm up consisted of 15 jumping jacks, 5 knee hugs, 10 body weight squats and 10 overhead weight squats with a PVC pipe to mimic the bar. After completing the warm-up, the participants stepped on the force plate and started with a squat jump with their hands on their hips. It was explained to the person that the first jump was 50% and the second jump was 75% effort; they were advised to listen to the count of 1,2,3 then jump when they were told to jump. After completing the warm-up round of the squat jump, they moved onto the actual testing of the squat jump where they were told to jump at 100% total max effort. The next jump that was completed was a countermovement jump with their hands on their hips as well. For this jump, they only did one warm-up jump at 75% total effort and then were ready to start the testing part of the countermovement jump. They were advised to do these jumps the same way the squat jump was completed. In between each squat jump and countermovement jump, they had 30 seconds to rest. The next part of testing was to do a snatch and clean on the force plate with the weight at 50% of the participant s 1RM. They started by warming up a snatch with the bar doing a set of three, and when that was completed they did 25% of their 1RM. After their warm-ups were completed, they moved over to the force plate and completed three individual snatches at 50% of their 1RM. In between each of the warm-up sets and the actual testing sets, they rested for one minute and couldn t go until they were told to get in position and go. The clean was warmed up and tested the same way as the snatches. All of the tests were completed on a Bertec force plate (6090, Columbus, Ohio, Bertec Corp. 2016) collecting data at 1,000 Hz. 2
RESULTS Results were determined by correlating the four movements (countermovement jump, squat jump, snatch, and clean) in regards to three different categories: rate of force development, peak force, and peak landing force. Pearson s correlations were used to determine the strength of each relationship. Results are shown in the tables and figures below. RFD PF PLF CMJ 0.223 1 Snatch 0.244 0.169 1 Clean -0.387 0.020 0.257 1 CMJ 0.946* 1 Snatch 0.855* 0.894* 1 Clean 0.846* 0.934* 0.967* 1 CMJ 0.750* 1 Snatch 0.360 0.598* 1 Clean 0.825* 0.706* 0.605* 1 3
DISCUSSION Though our sample size could have potentially affected the results, the Pearson s correlations still suggest that a few strongly statistically significant relationships occur in regards to peak force and peak landing force, which are shown in bold. In regards of rate of force development, there were no statistically strong relationships that occurred between the four movements performed. Specifically, peak force showed the strongest relationship between all four of the movements. Peak landing force showed strong relationships between the counter movement jump and squat jump. Peak landing force also showed a strong relationship between the clean and every weight lifting movement performed. These relationships were positive correlations, thus indicating that a person who can lift more weight or weight lifts versus one who does not, the weight lifter should be able to produce a higher level of rate of force development, peak force, and peak landing force. This meaning they should be able to jump higher. These results were not valid due to consistency in performing the movements because participants 100% efforts could be on different scales. Also, due to the sample size, it could have skewed the validity of the results. ACKNOWLEDGEMENTS The authors would like to thank the LaGrange College students & athletes who participated in this study and make this research possible. 4
REFERENCES Carlock, john M. "The relationship between vertical jump power estimates and weightlifting ability: a field-test approach." Galileo. Allen press publishing inc, aug. 2004. Web. Nov. 2016. Durovic, mark. "The relations between power and force variables realized during the squat jump with start performance in national level male sprint swimmers." Galileo. Facta universities, 2015. Web. Nov. 2016. Mackenzie, brian. "Sargent jump test." Sargent jump test or vertical jump test. Brianmac sports coach, 2016. Web. Nov. 2016. 5