Validity and reliability of high-resolution ultrasound imaging for the assessment of regional body composition in stage 5 chronic kidney disease patients undergoing continuous ambulatory peritoneal dialysis

Resistance Exercise in People With Stage-3 Chronic Kidney Disease: Effects of Training Frequency (Weekly Volume) on Measures of Muscle Wasting and Function

Background: Resistance training (RT) is a proven anabolic intervention in people living with and without chronic kidney disease (CKD). To date, there is a dearth of knowledge regarding the dose-response relationship of RT in the non-dialysis dependent CKD population. Therefore, we aimed to explore the effects of RT frequency (weekly volume) on established measures of muscle wasting and function in CKD.

Methods: Twenty people with stage-3 CKD (CKD-3) were allocated to either a low frequency (one-session per week, RT1) or higher frequency (three-sessions per week, RT3) 12-week RT programme consisting of lower extremity strengthening exercises. The two RT programmes were not volume matched. Assessment outcomes before and after the intervention included measures of total and regional body composition, muscle size and architecture, strength, physical function, and uraemic symptoms.

Results: Significant improvements over time in muscle size and architecture, strength, physical function, and uraemic symptoms were observed for both RT1 and RT3. Compared to RT1, participants who performed RT3 showed greater increases in vastus lateralis (VL) anatomical cross-sectional area (30.8% vs. 13.2%, p < 0.001) and pennation angle (36.3% vs. 17.5%, p = 0.008) after 12 weeks. In either group, there were no significant changes over time in mid-VL fascicle length, nor in measures of total body composition and upper arm muscle strength.

Conclusion: Despite the group differences observed in the VL physiological adaptations, the strength and physical function responses, as well as the reductions of uraemic symptoms, were similar whether training once or thrice weekly. Therefore, performing RT just once per week may be an effective pre-habilitation strategy for people with CKD-3.

Human skeletal muscle size with ultrasound imaging: a comprehensive review

Skeletal muscle size is an important factor in assessing adaptation to exercise training and detraining, athletic performance, age-associated atrophy and mobility decline, clinical conditions associated with cachexia, and overall skeletal muscle health. Magnetic resonance (MR) imaging and computed tomography (CT) are widely accepted as the gold standard methods for skeletal muscle size quantification. However, it is not always feasible to use these methods (e.g., field studies, bedside studies, large cohort studies). Ultrasound has been available for skeletal muscle examination for more than 50 years and the development, utility, and validity of ultrasound imaging are underappreciated. It is now possible to use ultrasound in situations where MR and CT imaging are not suitable. This review provides a comprehensive summary of ultrasound imaging and human skeletal muscle size assessment. Since the first study in 1968, more than 600 articles have used ultrasound to examine the cross-sectional area and/or volume of 107 different skeletal muscles in more than 27,500 subjects of various ages, health status, and fitness conditions. Data from these studies, supported by decades of technological developments, collectively show that ultrasonography is a valid tool for skeletal muscle size quantification. Considering the wide-ranging connections between human health and function and skeletal muscle mass, the utility of ultrasound imaging will allow it to be employed in research investigations and clinical practice in ways not previously appreciated or considered.