Ozaki, Guilherme Akio TamuraFilho, José Carlos Silva Camargo [UNESP]Garcia, Thiago AlvesCastoldi, Robson ChaconBelangero, William Dias2023-07-292023-07-292022-01-01Acta Ortopedica Brasileira, v. 30, n. SpecialIssue2, 2022.1413-7852http://hdl.handle.net/11449/248159Objective: Analyze the effects of aerobic and anaerobic training on different ergometers on muscle and cardiac hypertrophy in rats. Methods: The animals were separated into the following groups: Control (C), Aerobic Training in Water (ATW), Resistance Training in Water (RTW), Aerobic Training on Treadmill (ATT), and Resistance Training in Climbing (RTC). All training protocols were carried out for 4 weeks, 3 times/week. The cross-sectional area (CSA) of the gastrocnemius muscle cells and the areas of the cardiomyocytes were measured. Results: In the fast-twitch fibers, there was an increase in CSA in the RTW and RTC groups compared to the ATW (p<0.01 and p<0.01) and ATT groups (p<0.01 and p<0.01). In the slow-twitch fibers, the ATW and ATT groups demonstrated a lower CSA compared to the RTW (p=0.03 and p<0.00) and RTC groups (p<0.01 and p<0.01). In the cardiomyocytes, there was an increase in the area of the RTW and RTC groups compared to groups C (p<0.01; p<0.01), ATW (p=0.02; p<0.01), and ATT (p<0.01; p<0.01). Conclusion: The anaerobic training effectively promotes hypertrophy in the fast-twitch fibers and the cardiomyocytes. Level of Evidence V; Animal experimental studyengCardiacMuscle fibersMyocytesPhysical enduranceResistance trainingSkeletalArtigo10.1590/1413-785220223002e2480482-s2.0-85145946857