World-class Korean archers exhibit no unnecessary motion that can interfere with athletic performance, and maintain posture through consistency of motion and body stability (Heo, 2003). To improve archery technique, optimal body balance and force distribution, and control of breathing and heart rate are required, and these factors directly affect athletic performance (Kim, 2000;Kim & Kim, 2005). Imbalance of the body causes improper distribution of forces between bow arm and draw arm during bow extending in archery, resulting in inaccurate shooting (Korea Archery Association, 2011). It has been reported that archers can improve shooting efficiency through development of trunk muscles with improvement in body stability and motion (Yoon & Jung, 2002), and higher scores in archery can be achieved when all physical, mental, and physiological parameters are in simultaneous balance (Choi, 2013).
Many countries in Europe andAsia have recruited Korean archery coaches to provide systematic and scientific training, with the result that performance levels of archers throughout the world have gradually become equal. As a result, Korean archery has to recognize the training limitations of focus on physical fitness and technique, and must introduce new training methods based on the existing framework (Lee, 2011;Jang, 2006;Heo, 2003). Factors in archery such as repetitive movements and overload on the arms cause pains in the shoulder, neck, and low back. In addition, prolonged exercise in a unilateral posture can cause imbalance between the left and right muscles of the body (Yoon & Kim, 2012). Spinal imbalance often occurs in events such as archery, which impose unilateral forces on the spine. Incorrect coaching and excessive training of archers results in undesirable asymmetrical posture, so that most archers have postural imbalance (Kim, 2008).A comparison of bilateral and unilateral sports found that athletes in unilateral events had structural deformations of the spine and pelvis, with differences in spine curvature, pelvic slope, slope of bilateral trunk curvature, and trunk rotation (Lee, Choi, & Kim, 2010). Pelvic shapes of collegiate athletes were compared by event using a 3-dimensional KJSB