Bioimpedance analysis for identifying new indicators of exercise-induced muscle damage.

A noninvasive, immediate, and convenient method for assessing muscle tissue status during exercise-induced muscle damage (EIMD) has not been established. This study was designed to assess and determine parameters suitable for measuring EIMD after eccentric exercise, using multi-frequency bioimpedance analysis (BIA). Thirty-five young male participants performed dumbbell exercises with their left arm, and their BIA parameters were measured at various time points up to 168 h post exercise using a multi-frequency BIA device. At all-time points, intra and extracellular water content was greater in the left arm than in the right arm, whereas the impedance, reactance, resistance, and phase angle were lower in the left arm than in the right arm. Established EIMD indices, such as maximal isometric voluntary contraction, were measured and used in correlational analyses. Only reactance was correlated with biomarkers, indicating muscle damage (r = - 0.56 to - 0.49). Furthermore, reactance was found to correlate well with indirect indicators of EIMD, suggesting that it may be a suitable marker for evaluating EIMD. However, the relationship with the limited evaluation indices employed in this study is constrained. Future studies should investigate the correlation between reactance and direct damage indicators, such as structural damage, observed in biopsies.

Lower body bone fractures have high mortality rates and poor prognosis in the patients with hemodialysis.

INTRODUCTION: The objective of the current study was to investigate the association between lower body bone fractures occurring during maintenance hemodialysis and prognosis. METHODS: This study included 151 hemodialysis patients at the dialysis center of our hospital as of December 2017, and data were systematically gathered from medical records over a period of 5 years, concluding in December 2022. RESULTS: Fourteen patients, 3.0 per 100 person-years, in 151 hemodialysis patients suffered from lower body bone fractures. The ratio of males was significantly lower, and age was significantly higher in the lower body bone fracture group than in the no lower body bone fracture group. Duration of hemodialysis prior to entry into this study was significantly shorter in the lower body bone fracture group than in the no lower body bone fracture group. Serum albumin was significantly lower and alkaline phosphatase was significantly higher in the lower body bone fracture group than in the no lower body bone fracture group. Mortality rate was significantly higher in the lower body bone fracture group (85.7%) compared to no lower body bone fracture group (28.5%) (p = 0.01). Kaplan-Meier survival curves for mortality showed that lower body bone fracture group had poor prognosis compared to no lower body bone fracture group. Multivariable-adjusted odds ratio for mortality were significantly higher for cases with lower body bone fractures. CONCLUSION: Lower body bone fractures have high mortality rates and poor prognosis in the patients with hemodialysis.

The Effect of Prior Creatine Intake for 28 Days on Accelerated Recovery from Exercise-Induced Muscle Damage: A Double-Blind, Randomized, Placebo-Controlled Trial.

Despite the known beneficial effects of creatine in treating exercise-induced muscle damage (EIMD), its effectiveness remains unclear. This study investigates the recovery effect of creatine monohydrate (CrM) on EIMD. Twenty healthy men (21-36 years) were subjected to stratified, randomized, double-blind assignments. The creatine (CRE) and placebo (PLA) groups ingested creatine and crystalline cellulose, respectively, for 28 days. They subsequently performed dumbbell exercises while emphasizing eccentric contraction of the elbow flexors. The EIMD was evaluated before and after exercise. The range of motion was significantly higher in the CRE group than in the PLA group 24 h (h) post exercise. A similar difference was detected in maximum voluntary contraction at 0, 48, 96, and 168 h post exercise (p = 0.017-0.047). The upper arm circumference was significantly lower in the CRE group than in the PLA group at 48, 72, 96, and 168 h post exercise (p = 0.002-0.030). Similar variation was observed in the shear modulus of the biceps brachii muscle at 96 and 168 h post exercise (p = 0.003-0.021) and in muscle fatigue at 0 and 168 h post exercise (p = 0.012-0.032). These findings demonstrate CrM-mediated accelerated recovery from EIMD, suggesting that CrM is an effective supplement for EIMD recovery.