The following is the summary of “Effect of Long-term Exercise Training on Physical Performance and Cardiorespiratory Function in Adults With CKD: A Randomized Controlled Trial” published in the January 2023 issue of Kidney diseases by Weiner, et al.

In older persons with advanced CKD and comorbidities, the safety and efficacy of long-term exercise training to reduce physical functional decline remain unclear. Randomized controlled trial using many centers and a parallel group design. From clinics in Baltimore and Boston, researchers enrolled adults aged 55 and up with an estimated glomerular filtration rate (eGFR) of 15 to 45 mL/min/1.73 m2. Participants were randomly allocated to either a group health education control intervention or 12 months of supervised in-center exercise training consisting primarily of aerobic but also muscle-strengthening activities.

At 6 and 12 months, peak oxygen consumption (Vo2peak) on a graded exercise treadmill test and distance traveled on a 6-minute walk test were used to measure cardiorespiratory fitness and submaximal gait, respectively. Alterations in lower limb function estimated glomerular filtration rate, albuminuria, glycemia, blood pressure, and body mass index were secondary outcomes. The average age of the 99 participants was 68 years, 62% were African American, and the average eGFR was 33 mL/min/1.73 m2. Additionally, 59% of the participants were diabetic, and 29% of the individuals had coronary artery disease. For the first 6 months after being assigned to exercise, 59% of participants were present at all scheduled sessions. The majority of people who engaged in physical activity saw no harmful effects at all. Exercisers had a greater increase in aerobic capacity at 6 months (17.9 ± 5.5 vs. 15.9±  7.0 mL/kg/min, P=0.03), but this was not maintained at 12 months. 

As measured by the 6-minute walk distance, the exercise group saw the greatest increase (98 feet, after adjustment; P=0.02 for treatment by time interaction). Results from the Timed Up and Go Test (P=0.04) and the Short Physical Performance Battery (P=0.8) showed that the exercise group fared better. It appears that the target number of participants in the sample was not met. Dropout and loss to follow-up were higher than expected. Aerobic and strength exercise training in a center setting for 12 months was safe and linked with improvements in physical functioning among persons aged  ≥55 years with CKD stages 3b-4 and a high level of medical comorbidity.