Association between vitamin D deficiency and exercise capacity in patients with CKD, a cross-sectional analysis.

Background: Evidence is growing for a role of vitamin D in regulating skeletal muscle mass, strength and functional capacity. Given the role the kidneys play in activating total vitamin D, and the high prevalence of vitamin D deficiency in Chronic Kidney Disease (CKD), it is possible that deficiency contributes to the low levels of physical function and muscle mass in these patients.

Methods: This is a secondary cross-sectional analysis of previously published interventional study, with in vitro follow up work.

The association of muscle size, strength and exercise capacity with all-cause mortality in non-dialysis-dependent CKD patients.

Background/objective: Patients with chronic kidney disease (CKD) are commonly reported to exhibit skeletal muscle wasting, reduced strength and exercise capacity. Evidence from patients with end-stage renal disease (ESRD) demonstrates these factors are associated with mortality, but it is unclear whether this relationship exists earlier in the illness. Our objective was to determine whether muscle size, strength or exercise capacity was associated with all-cause mortality, unscheduled hospital admissions or time to ESRD in patients not requiring dialysis.

Reductions in skeletal muscle mitochondrial mass are not restored following exercise training in patients with chronic kidney disease.

Patients with chronic kidney disease (CKD) exhibit reduced exercise capacity, poor physical function and symptoms of fatigue. The mechanisms that contribute to this are not clearly defined but may involve reductions in mitochondrial function, mass and biogenesis. Here we report on the effect of non-dialysis dependent CKD (NDD-CKD) on mitochondrial mass and basal expression of transcription factors involved in mitochondrial biogenesis compared to a healthy control cohort (HC).

Peak aerobic capacity from incremental shuttle walk test in chronic kidney disease.

Background: Assessment of cardiorespiratory fitness is an important outcome in chronic kidney disease (CKD). We aimed to develop a predictive equation to estimate peak oxygen uptake (VO ) and power output (W ), as measured during a cardiopulmonary exercise test (CPET), from the distance walked (DW) during the incremental shuttle walk test (ISWT).

Methods: Thirty-six non-dialysing patients with CKD [17 male, age: 61 ± 12 years, eGFR: 25±7 ml/min/1.

Ultrasound assessment of muscle mass in response to exercise training in chronic kidney disease: a comparison with MRI.

Background: Chronic kidney disease (CKD) is a catabolic condition associated with muscle wasting and dysfunction, which associates with morbidity and mortality. There is a need for simple techniques capable of monitoring changes in muscle size with disease progression and in response to interventions aiming to increase muscle mass and function. Ultrasound is one such technique; however, it is unknown how well changes in muscle cross-sectional area (CSA) measured using ultrasound relate to changes in whole muscle volume measured using magnetic resonance imaging.

Association of self-reported physical function with survival in patients with chronic kidney disease.

Background: Reduced physical function is associated with an increased risk of mortality among patients with chronic kidney disease (CKD) not requiring renal replacement therapy (RRT). Assessments of physical performance can help to identify those at risk for adverse events. However, objective measures are not always feasible and self-reported measures may provide a suitable surrogate.

Twelve weeks of supervised exercise improves self-reported symptom burden and fatigue in chronic kidney disease: a secondary analysis of the 'ExTra CKD' trial.

Background: Chronic kidney disease (CKD) patients experience a high symptom burden including fatigue, sleep difficulties, muscle weakness and pain. These symptoms reduce levels of physical function (PF) and activity, and contribute to poor health-related quality of life (HRQoL). Despite the gathering evidence of positive physiological changes following exercise in CKD, there is limited evidence on its effect on self-reported symptom burden, fatigue, HRQoL and physical activity.

The association of physical function and physical activity with all-cause mortality and adverse clinical outcomes in nondialysis chronic kidney disease: a systematic review.

Objective: People with nondialysis-dependent chronic kidney disease (CKD) and renal transplant recipients (RTRs) have compromised physical function and reduced physical activity (PA) levels. Whilst established in healthy older adults and other chronic diseases, this association remains underexplored in CKD. We aimed to review the existing research investigating poor physical function and PA with clinical outcome in nondialysis CKD.

The "Minimum Clinically Important Difference" in Frequently Reported Objective Physical Function Tests After a 12-Week Renal Rehabilitation Exercise Intervention in Nondialysis Chronic Kidney Disease.

Objective: Chronic kidney disease patients are characterized by impaired physical function. The goal of exercise-based interventions is an improvement in functional performance. However, improvements are often determined by "statistically significant" changes.

Characterising skeletal muscle haemoglobin saturation during exercise using near-infrared spectroscopy in chronic kidney disease.

Background: Chronic kidney disease (CKD) patients have reduced exercise capacity. Possible contributing factors may include impaired muscle O utilisation through reduced mitochondria number and/or function slowing the restoration of muscle ATP concentrations via oxidative phosphorylation. Using near-infrared spectroscopy (NIRS), we explored changes in skeletal muscle haemoglobin/myoglobin O saturation (SMO%) during exercise.

Quality over quantity? Association of skeletal muscle myosteatosis and myofibrosis on physical function in chronic kidney disease.

Background: Chronic kidney disease (CKD) is characterized by adverse changes in body composition, which are associated with poor clinical outcome and physical functioning. Whilst size is the key for muscle functioning, changes in muscle quality specifically increase in intramuscular fat infiltration (myosteatosis) and fibrosis (myofibrosis) may be important. We investigated the role of muscle quality and size on physical performance in non-dialysis CKD patients.

Test-retest reliability, validation, and "minimal detectable change" scores for frequently reported tests of objective physical function in patients with non-dialysis chronic kidney disease.

Physical function is an important outcome in chronic kidney disease (CKD). We aimed to establish the reliability, validity, and the "minimal detectable change" (MDC) of several common tests used in renal rehabilitation and research. In a repeated measures design, 41 patients with CKD not requiring dialysis (stage 3b to 5) were assessed at an interval of 6 weeks.

Physiological benefits of exercise in pre-dialysis chronic kidney disease.

Chronic kidney disease (CKD) is strongly associated with cardiovascular disease and muscle wasting, arising from numerous factors associated with declining renal function and lifestyle factors. Exercise has the ability to impact beneficially on the comorbidities associated with CKD and is accepted as an important intervention in the treatment, prevention and rehabilitation of other chronic diseases, however, the role of exercise in CKD is overlooked, with the provision of rehabilitation programmes well behind those of cardiology and respiratory services. Whilst there is now a large evidence base demonstrating the efficacy and safety of exercise training interventions in patients receiving dialysis, and this is now becoming incorporated into clinical guidelines for treatment of dialysis patients, there is a paucity of research evaluating the effectiveness of exercise in patients with CKD who are not on dialysis.

Cancer cachexia prevention via physical exercise: molecular mechanisms.

Cancer cachexia is a debilitating consequence of disease progression, characterised by the significant weight loss through the catabolism of both skeletal muscle and adipose tissue, leading to a reduced mobility and muscle function, fatigue, impaired quality of life and ultimately death occurring with 25-30 % total body weight loss. Degradation of proteins and decreased protein synthesis contributes to catabolism of skeletal muscle, while the loss of adipose tissue results mainly from enhanced lipolysis. These mechanisms appear to be at least, in part, mediated by systemic inflammation.