A senior interested in body building completed a project involving the analysis of a Soloflex machine. The objective of the project was to involve the senior in a research project, and to determine the resistance curve for a bench press exercise using a Soloflex Exercise machine. In completing this project, the student obtained dimensions of the components of the machine, and made appropriate calculations to determine the resistance curve. To perform an exercise, the barbell arm is attached with a pin to the loading piece. Weight straps of equal rating are placed on both sides of the load and barbell arm pins. Pushing upward on the barbell arm will stretch the weight straps which provides resistance to the motion of the barbell arm. The straps were stretched with a Tinius-Olsen machine to determine the force vs. deflection behavior for one pair each of 2.5 lbf, 5 lbf, 10 lbf, 25 lbf, and 50 lbf weight straps. Once known, these data are then used to calculate the force required at the barbell arm to perform a bench press exercise for a particular resistance or "weight." Note that several different exercises can be performed with this machine due to its versatility, but the focus here is on a simple bench press, for which the resistance curve was determined. This study was completed by a senior at the University of Memphis. Data were obtained for a number of matched weight straps, but all data are not presented here. The essential components of a senior project from project planning to project management to project completion are described.

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