The importance of trunk muscles in providing adequate spine stability is well established and the role of trunk muscles during a variety of tasks has been well documented. Swiss balls are a common addition to trunk muscle exercises. In fitness centres and rehabilitation centres, Swiss balls are often touted as being superior to ground based exercises in their ability to recruit trunk muscles (rectus abdominis, external oblique, internal oblique, erector spinae). Considering the ubiquity of Swiss balls, one research question was posed: Does the addition of a Swiss ball to bridging exercises influence trunk muscle activity?
The implications of this study are twofold: 1. Modifying trunk muscle activity could be important in the safety and efficacy of rehabilitation exercises when a low level of trunk muscle activity is desired; and 2. Identifying exercises which maximally activate the trunk muscles may make it possible to develop an efficient and less time consuming general strength program that conditions the trunk muscles.