INTRODUCTION

Our project examining the differences in joint angles in the upper arm during push-ups with narrow and normal hand positions. In answering this question, we will be able to determine how each of theses positions will affect the stress put on the joints and the muscles and ligaments. We will also look at the technique used in each movement, which will tell us about the range of motion involved in each movement. Range of motion can be important in determining injuries to the joints. Movements that use the same muscle groups as push-ups are involved in other daily activities as well. Those daily activities that produce more range of motion to particular joints i.e. the shoulder and elbow joints, tend to induce more pain (Triffitt 1998). In our movement analysis, we will hopefully be able to determine the range of motion that is suitably comfortable to yield less pain.

We will analyze these aspects of the experiment by observing the joint angles seen in each movement marked by the joint markers and which muscle groups seem to be activated. While these positions are closely related, they may have completely different muscle groups and may have completely different joint angles, which would mean they each have different stress levels on the joints. Another factor we will look at is time taken to produce each movement. By looking at the time differences, we will be able to see which movement is more "efficient" time wise which may have an affect on the overall efficiency of the movement. In answering these questions, we will have determined which of these movements is a more efficient exercise and which one is less likely to cause injury to the joints and muscles involved. We will accomplish this by performing two different sets of push-ups and determining which push-up style (narrow or wide) is less stressful on the joints.