Downloaded from http://journals.lww.com/acsm-msse by BhDMf5ePHKbH4TTImqenVE5wmW8EcRnjAL15V5hf9ouSr8ZNSi0t3niDPcuhi2fZ on 09/17/2020 586 2143 Board #299 May 30 3:30 PM - 5:00 PM Elastic Band Resistance Training Effects on Strength and Sleep of Shift Workers Marco T. de Mello, Diego A. Borba, Lucas A. Facundo, Fernanda V. Narciso, Andressa Silva. Universidade Federal de Minas Gerais, Belo Horizonte, Brazil. Email: tmello@demello.net.br (No relationships reported) PURPOSE: To determine the effect of elastic band resistance training in strength, muscle mass and sleep of shift workers. METHODS: Twelve sedentary workers with weekly work schedule of 12 hours of work for 36 hours of rest (Age: 42.3±8.8 years, Body Mass Index: 27.6±3.7 Kg), performed 16 elastic band training sessions (2 sets until failed; 3 times by week, for 16 weeks). The initial training load was determined by color and/or number of elastic band test to 10RM (shoulder abduction and biceps curl) and 20RM to seated low row exercise. The push up exercise no used elastic band. In following training sessions, the participants were instructed to perform the four exercises in the maximal number of repetition possible each new session. The estimated arm muscle area, exercises repetition number and sleep (sleep duration, sleep latency, sleep efficiency and weak after sleep onset) were assessment pre and post-training. The sleep variables were determined by actigraphy technique for during seven days. The pre and post-test comparisons were made using paired t test. RESULTS: The arm muscle area, was improved after training (7015.5±1859.3 vs. 7571.179±1723.625, p<0.05) as well as exercises repetition number (shoulder abduction: 10.3±0.6 vs. 22.3±4.7; push up: 11.2±3.2 vs. 19.8±6.7; seated low row: 20.2±1.0 vs. 37.1±8.4; biceps curl: 10.2±0.6 vs. 23.7±7.7, p<0.001). There is no change in sleep variables after training (Sleep Duration: 386.3±36.7 vs. 384.6±43.8 min; Sleep Latency: 28.5±32.7 vs. 14.0±15.0 min; Sleep Efficiency: 86.7±7.7 vs. 86.5±7.5%; Weak after sleep onset: 34.4±22.2 vs. 38.3±23.7 min, p>0.05). CONCLUSIONS: Elastic band resistance training improved the strength and muscle mass of shift work without to change their sleep quality of shift workers. Supported by UFMG, FAPEMIG, MAFRE Foundation, CAPES and CNPQ. 2144 Board #300 May 30 3:30 PM - 5:00 PM Impact Of Sleep Deprivation On Flexibility Performance Fernanda Veruska Narciso, Beatriz M. Pereira, Andressa Silva, Mauro H. Chagas, Matheus M. Reis, Carlos Amaral Costa, Valdenio M. Brant, Lucas A. Facundo, Aline A. Cruz, Marco Tulio de Mello. Universidade Federal de Minas Gerais, Belo Horizonte, Brazil. (No relationships reported) PURPOSE: The purpose of this study was to verify the impact of sleep deprivation in flexibility of young adults. METHODS: Ten sedentary male young adults (Mean age: 24.3 ± 3.8 years old, body mass index: 24,8 ± 2.5 kg/m 2 ) wore wrist actigraph before and during the 36-h of sleep deprivation to measure sleep-wake cycle, and Passive Maximal Range of Motion (PROM max ) was evaluated by the modified knee extension test with a fleximeter in 4 different moments: at onset of sleep deprivation (8:00am, day 1 = baseline), and after 12h (8:00pm, day 1), 24h (8:00am, day 2) and 36h (8:00pm, day 2) of sleep deprivation. Volunteers lay back with the hip flexed at 90º, and the initial knee ROM (0º) was considered as 90º right knee flexion. PROM max was measured 06 times, and mean values at the 03 lasts was analysed. Analyzes of Paired-Samples Variance were used to compare the variables in four moments, and statistical significance set at p< 0.05. RESULTS: PROM max values showed significative difference (F 1,38 = 51.148, p < 0.001) after 12h (71.7 ± 0.27°; CI 95% = 66.2-77.2), 24h (71.0 ± 2.6°; CI 95% = 65.8-76.3) and 36h (69.8 ± 2.6°; CI 95% = 64.5-75.1) of sleep deprivation compared with baseline (73.0 ± 2.7; CI 95% = 67.6-78.4). Moreover, there was decrease of PROM max (F 1,38 = 17.951, p < 0.001) from 12 h to 36 h and from 24 h to 36 h of sleep deprivation. CONCLUSION: Our findings suggest that sleep deprivation may have a negative impact on PROM max . Furthermore, 12 h and 36 h after baseline moment showed reduction of the PROM max , even as the time of maximal circadian rhythm values (acrophase) have generally observed between 4:00pm and 8:00pm. The duration of sleep deprivation and the circadian time are important in determining the impairment in passive flexibility performance. Acknowledgment: CAPES, CNPQ, FAPEMIG, CEMSA, CEPE. 2145 Board #301 May 30 3:30 PM - 5:00 PM Effects Of Sleep Deprivation On Histopathological Changes And Oxidative Damage In Different Type Muscle Fibers Marcos Mônico-Neto 1 , Kil Sun Lee 1 , Daniel Araki Ribeiro 2 , Caroline Margonato Cardoso 2 , Luciana Le Sueur Maluf 2 , Hanna Karen Moreira Antunes 1 . 1 Federal University of Sao Paulo, Sao Paulo, Brazil. 2 Federal University of Sao Paulo, Santos, Brazil. Email: marcosmoniconeto@gmail.com (No relationships reported) Previous studies has shown that sleep deprivation (SD) induces muscle atrophy and histopathological changes, however, these effects may be different considering the type muscle fiber. PURPOSE: to analyze histopathological changes and oxidative damage after SD in different types of muscle fibers (oxidative and glycolytic) of rats. METHODS: 20 Wistar male rats (3 months, 300-350 g) were distributed in two groups, control group (CTL, n=10) and SD by 96 h group (SD96, n=10). The SD96 group was sleep deprived on consecutive 96 h, while the CTL group remained in the housing box. At the end of SD, the soleus and plantar muscles were analyzed for lipid peroxidation by concentrations of malondialdehyde (MDA), oxidative damage to DNA by nuclear labeling of 8-OHdG and histopathological changes. RESULTS: it was observed increased MDA concentrations in the soleus of SD96 compared to CTL (0.0134±0.0009 vs 0.0121±0.0009 mmol/mg, P=0.01). Comparison between muscles revealed that the soleus had higher concentrations of MDA than plantar to both groups (P<0.001 for both). Regarding 8-OHdG, there was increased nuclear labeling to the plantar muscle in the SD96 compared to CTL (25.4±3.6 vs 7.2±1.9 positive cells, P<0.001). In the soleus, greater nuclear labeling was observed in SD96 compared to CTL (60±13.6 vs 9.6±3.6 positive cells, P<0.001), already the comparison between the muscles revealed a greater nuclear labeling of 8-OHdG in the soleus muscle compared to plantar in the SD96 group (P<0.001). The histopathological evaluation of the soleus revealed the presence of interstitial edema in SD96 compared to CTL (19.5±4.2% vs 0%, P<0,001), associated with intense cellular infiltration, alterations in the arrangement of muscle fibers, as well as areas of tissue degeneration and reduction of muscle parenchyma (72,7±2,7 vs 92,4±1,6%, P<0,01). In the plantar muscle, the changes were more subtle, with slight increase in cellularity in the SD96 and fibers presenting smaller cross-sectional area in SD96 group. CONCLUSIONS: SD induces degenerative process and oxidative damage in the skeletal muscle, being more intense in type I fibers. 2146 Board #302 May 30 3:30 PM - 5:00 PM The Effect of Acute Sleep Restriction on Running Mechanics during an Exhaustive Run Reiley T. Bergin, Nicholas R. Heebner, Cheyenne DeRaymond, Amanda C. Glueck, John Abt, FACSM, Stuart Best. University of Kentucky, Lexington, KY. (Sponsor: John Abt, FACSM) (No relationships reported) Copyright © 2019 by the American College of Sports Medicine. Unauthorized reproduction of this article is prohibited.