Dissertations and Theses @ UNI


Open Access Thesis


Jumping; Volleyball for women--Physiological aspects;


The purpose of this study was to investigate the effect of experimental alterations in relatively small amounts of excess weight on vertical jump height. The objective was to use the consequences of changes in body weight on vertical jump performance. The subjects were 19 Division I college volleyball players from the University of Northern Iowa. The mean value for age was 20.04 years, the mean height was 176.2 cm, the mean weight was 71.58 kg, and the mean percentage of body fat was 22.60% for all subjects. Each subject was tested under six weight conditions: (a) normal body weight, (b) one pound added, (c) two pounds added, (d) three pounds added, (e) four pounds added, and (f) five pounds added. The weight was added by means of a harness vest which secured the weight to the waist. Subjects completed three jumps at each of the six weight conditions. The mean vertical jump scores for the unweighted condition, one pound added, two pounds added, three pounds added, four pounds added, and five pounds added were 22.60 in., 22.29 in., 22.26 in., 22.15 in., 21.67., and 21.46 in. respectively for all subjects. Statistical analysis revealed that height jumped was affected by the added weight (E = 15.867, p < .01 ). Each of the experimentally altered weight conditions were then compared to the baseline unweighted condition. Results indicated that there was no significant difference in vertical jump performance with the addition of one pound added p - .0634) or two pounds added p =.0282) when compared to the unweighted condition. There was, however, a significant difference in the three pound condition p = .0000), the four pound condition p = .0000), and the five pound condition p = .0000). The actual difference in height jumped between the unweighted conditions and the five weighted conditions were .316 in. for the one pound condition, .342 for the two pound condition, .456 in. for the three pound condition, .938 in. for the four pound condition, and 1.15 in. for the five pound condition. In conclusion, minor fluctuations in weight of up to two pounds seemed to have little affect on vertical jump performance. However, when adding weight of three, four, and five pounds a decrement in performance was observed.

Year of Submission


Degree Name

Master of Arts


School of Health, Physical Education, and Leisure Services

First Advisor

Iradge Ahrabi-Fard

Second Advisor

Larry Hensley

Third Advisor

Carol Phillips


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Date Original


Object Description

1 PDF file (63 leaves)