The aim of the present study was to investigate the effects of unilateral shoulder bag weight and heel heights on trunk muscle activities. This study recruited 40 healthy women in their twenties. Electromyography activities of rectus abdominis muscle, external abdominal oblique muscle, internal abdominal oblique muscle and erector spinae muscle during standing position were measured using a surface electromyography system. The overall muscle activities of the trunk muscles were significantly increased in the contralateral trunk muscles (p<.05). Inaddition, the trunk muscles overall activities on the contralateral side without the shoulder bag was positive correlation with the heel height and unilateral shoulder bag weight (p<.05). Both high-heeled wear and unilateral shoulder bags are fashion items that cause asymmetry in the trunk muscles of women in their twenties. These findings suggest that the increase in the weight and heel height of the unilateral shoulder bag in women cause asymmetry of trunk muscle activities.

INTRODUCTION
 METHODS
  Subjects
  Procedures
  Statistical analysis
 RESULTS
  Changes in trunk muscle activities with increasingshoe heights by shoulder bag weight
  Changes in trunk muscle activities with increasingshoulder bag weight by shoe heights
  Correlation between muscle activity by the heelheight and muscle activity by shoulder bag weight
 DISCUSSION
 CONCLUSIONS
 REFERENCES

• Nyeon Jun Kim(Pohang University)
• Joong San Wang(Howon University) Corresponding author