by the American College of Sports Medicine. Unauthorized reproduction of this article is prohibited. Copyright @ 2010 388 those testing times during a concentrically loaded isometric maximal voluntary contraction (MVC). RESULTS: A repeated-measures design was used with exposure as a nine level independent variable: 30, 60, 90, 120, 150, 180, 210 and 240 min of exposure, each associated with a pre-test (0 min). The repeated measures ANOVA revealed statistically significant within subjects main effects average EMG amplitude (AEMG) and exposure level. A significant change in AEMG from the pre measure was observed beginning at the 150 minute interval and continuing through the 240 minute interval (p=.036, .021, .029, .019; respectively from 150-240). No statistically significant difference from the pre test measure was observed over the 30 to 120 intervals. The AEMG of the ES significantly declined after 120 minutes of walking on a flat surface and continued to decrease at the subsequent time intervals. CONCLUSIONS: There may be attenuation in AEMG of the ES after 2 hours of walking on a flat surface. Further, workers who sustain daily, prolonged walking could be susceptible to chronic low back fatigue or injury. These findings provide preliminary information to researchers seeking to provide practical information to industry regarding work practices and personal protective equipment (boots) decision processes. 1755 Board #192 June 2 3:30 PM - 5:00 PM Age-related Change of Trunk Muscles in Japanese Male and Female Meiko Asaka, Mitsuru Higuchi, FACSM. Waseda University, Saitama, Japan. (Sponsor: Mitsuru Higuchi, FACSM) Email: meiko-j@suou.waseda.jp (No disclosure reported) The muscles of the trunk play an essential role in stabilizing and/or transferring the body in various movements in activities of daily living, and it is important to prevent the age-related decrease of these muscles for elderly people. It has been shown that the age-related wasting of rectus abdominis is more remarkable than other muscles of the body. However, it is unclear whether there are differences in the age-related changes of other trunk muscles and the site difference in each trunk muscle. PURPOSE: The purpose of this study was to examine the age-related change of the muscles in the trunk. METHODS: Subjects included 155 Japanese healthy male and 50 female aged 20-69 years, and divided into 5 age groups in 10-year increments. The cross- sectional areas (CSAs) of trunk muscles were scanned at umbilical level using by magnetic resonance imaging. We analyzed the sum CSA of the right and left rectus abdominis, oblique abdominal, psoas major, quadrates lumborum and erector spinae. Maximal oxygen uptake (VO2max) was assessed by a progressive continuous test to exhaustion on a cycle ergometer as an index of cardiorespiratory fitness (CRF). RESULTS: The total trunk muscle CSA in the 50s and 60s were smaller than the 20s in both sexes. The 60s had 15% and 26% lower total trunk muscle CSA than the 20s in male and female, respectively. There were no differences in rectus abdominis and oblique abdominal between the age groups in both sexes. On the other hand, in male, psoas major, quadrates lumborum and erector spinae CSAs in the 60s were smaller by 67%, 67% and 25% than those in the 20s in men, respectively. In female, the 60s had 34%, 53% and 31% smaller psoas major, quadrates lumborum and erector spinae CSAs than the 20s, respectively. The interaction between age group and sex (age×sex) was significant (P < 0.01) for psoas major CSA. The total trunk muscles CSA correlated with VO2max only in male, but there was no significant correlation between the trunk muscles CSA and VO2max adjusted by age in both sexes. CONCLUSIONS: These results suggest that the muscles in the trunk decrease with aging regardless of CRF level, especially deep muscles in the trunk for both male and female, and there is sex difference in the magnitude of the age-related change. 1756 Board #193 June 2 3:30 PM - 5:00 PM Profile Level Of Physical Activity And Quality Of Sleep In Patients With Fibromyalgia Andressa Silva, Raquel Campos, Marcos Monico, Sandra S. Queiroz, Hanna K. Antunes, Sergio Tufik, Marco T. Mello. Federal University of Sao Paulo, Sao Paulo, Brazil. Email: silvadressa@gmail.com (No disclosure reported) The fibromyalgia is a chronic non-inflammatory pain syndrome, characterized by the presence of diffuse pain in the body for a period of three months, and as a consequence of the reduction in physical activity level, but also reported complaints of sleep disturbances. PURPOSE: To describe and correlate the level of physical activity and quality of sleep in patients with fibromyalgia. METHODS: We evaluated 15 female patients, mean age of 58.47±7.0 with a diagnosis of fibromyalgia. This is a cross-sectional study with application of questionnaires, self-administered. The assessment of the level of physical activity was made by the International Physical Activity Questionnaire - IPAQ, the chronotype by questionnaire chronotype morning-afternoon and the quality of sleep using the Pittsburgh Questionnaire, to assess sleepiness using the Sleepiness Scale of Epworth. All data were analyzed by statistical program SPSS Statistics Version 17. The tests used were the “student t” for testing the homogeneity of the sample. Test for equality of variance and Levene X2 Fischer to establish the relationship between the IPAQ questionnaires/Pittsburgh and IPAQ/Epworth. RESULTS: The level of physical activity of patients revealed that 67% were minimally active, while 33% were inactive with regard to the quality of sleep 94% had complaints of sleep, 53% have daytime sleepiness. CONCLUSIONS: Given that the practice of physical exercise is now considered a form of treatment for complaints related to sleep, it is believed that one of the alternative treatment for patients with fibromyalgia would be implementing a routine of physical exercise on a gradual and progressive. Since these women have in addition to all the pain of fibromyalgia, a low level of physical activity and sleep disorders. Supported by AFIP and FAPESP (CEPID #98/14303-3 to S.T. and #07/56620-6 to A.S. and #09/05442-6 to R.M.S.C.). Sergio Tufik and Marco Túlio de Mello are recipients of fellowships from CNPq, FADA - UNIFESP, CEPE. 1757 Board #194 June 2 3:30 PM - 5:00 PM The Role of the Dynamic Stretching in Shoulder Overuse Syndrome in Elite Volleyball Players. Antonio Ammendolia, Andrea Ferragina, Teresa Iona, Cristiano Nisticò, Maria Cristina Papaianni, Rosario Scarfone. University of Catanzaro, Catanzaro, Italy. Email: ammendolia@unicz.it (No disclosure reported) The theory of internal impingement holds that, in overhead athletes, repeated contact between the undersurface of the rotator cuff and the posterosuperior glenoid rim leads to articular-sided partial-thickness rotator cuff tears with flexibility deficits, strength deficits, or both along the kinetic chain. So it is very important to protect as soon as possible the athlete’s shoulder from the impingement to avoid the rotator cuff tears. PURPOSE: The aim of the study is to demonstrate that the dynamic stretching is useful to improve the flexibility and stability of the athlete’s shoulder, reducing the risk of the “overuse syndrome”. METHODS: Informed consent was obtained and we enrolled 20 volleyball top level players (20.4±0.7 yrs). We evaluated the flexibility and stability of the shoulder, for each athlete, using a score schedule ASO (Athletic Shoulder Outcome) before the beginning, in the middle and after the end of the championship.