Abstract
[Purpose] In this study, we compared trunk mobility in the standing position while carrying a shoulder bag on the habitual side with those of the bag carried on the non-habitual side and examined the relationship between trunk lateral bending exercise and the habitually used side. [Subjects] The subjects were 10 healthy persons aged 20.1 ± 1.5 years. [Method] Using a 3D motion analysis system, we measured trunk mobility while carrying a shoulder bag in the standing position and compared the left and right sides. We also compared the mobility of the left and right sides in lateral bending, and examined the relationship with the habitual side. [Results] On the habitual side, increases in lower trunk lateroversion on the contralateral side and backward inclination were seen. During lateral bending, increases in lateroversion on the habitually carried side and contralateral side were found. [Conclusion] We consider that for cases of lumbar pain such as those arising from asymmetric lower spine mobility in lateral bending, or instability arising from posterior tilt of the lumbar spine, guidance and caution about maintenance of standing posture while carrying a shoulder bag are necessary.