AUTHOR=da Silva Victor , Corrêa Hugo , Neves Rodrigo , Deus Lysleine , Reis Andrea , Souza Michel , dos Santos Cláudio , de Castro Danilo , Honorato Fernando , Simões Herbert , Moraes Milton , Schoenfeld Brad , Prestes Jonato , Rosa Thiago 

TITLE=Impact of Low Hemoglobin on Body Composition, Strength, and Redox Status of Older Hemodialysis Patients Following Resistance Training

JOURNAL=Frontiers in Physiology

VOLUME=Volume 12 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2021.619054

DOI=10.3389/fphys.2021.619054

ISSN=1664-042X

ABSTRACT=Introduction: The purpose of this study was to: (i) investigate the effect of six months of resistance training (RT) on body composition, muscle strength, hematological patterns, and redox profile in maintenance hemodialysis (HD) patients, and; (ii) evaluate the effects of baseline concentrations of hemoglobin on the RT response. 
Methods: One hundred fifty-seven subjects with chronic kidney disease (CKD) were randomly allocated into two groups: Control (CTL, [n = 76]) and RT (n = 81). A first visit was required for anamnesis and anthropometric measurements. Venous blood samples were collected at baseline and after twenty-four weeks of training in all patients for the analysis of clinical and redox balance markers. The RT program spanned six months and consisted of three sets of 8 to 12 repetitions with a rating of perceived exertion between 5-8 for three weekly sessions. Each exercise session was performed in twelve resistance exercises and it least for approximately 40 minutes.
Results: The main results demonstrated that RT decreased waist circumference by 3%, and decreased thiobarbituric reactive species (TBARS) by 28%. Moreover, RT increased handgrip strength by 28.4%, fat-free mass by 4.1%, hemoglobin by 5%, iron by 33.4%, glutathione by 121%, and Trolox equivalent antioxidant capacity by 14.2% (p < 0.05). Low hemoglobin concentrations impaired the effect of RT on fat-free mass gain. 
Conclusion: Six months of RT in HD patients improved clinical parameters, such as hemoglobin, iron, body composition, and redox balance, while low hemoglobin concentration impaired exercise-benefits on fat-free mass in patients with CKD. These findings can contribute to a better clinical application of RT in the maintenance of hemodialysis patients.