Protein and Exercise Training in Chronic KIDNEY Disease (PET KIDNEY)

Protein Supplementation and Exercise Training to Increase Muscle Protein Synthesis Rates in Patients With Advanced Chronic Kidney Disease

When patients progress to the final stage of chronic kidney disease (CKD) and require hemodialysis treatment, they typically have lost so much muscle function that they are no longer physically independent. However, due to disease- and hemodialysis-related muscle catabolism, dietary protein and exercise interventions are only capable to attenuate the decline in physical function of patients on hemodialysis treatment. Therefore, lifestyle interventions to increase muscle function should be implemented before hemodialysis is required. However, it is still a matter of debate whether muscle protein synthesis rates of patients with advanced CKD can be increased with a patient-tailored dietary protein and exercise intervention.Therefore, the current study will assess MPS rates during habitual lifestyle and during an interventional program including dietary protein and exercise in patients with advanced CKD. In addition, we will compare MPS rates during free-living conditions between patients with advanced CKD and healthy controls.

Study Overview

• Status: Completed
• Conditions: Kidney Diseases; Muscle Loss
• Intervention / Treatment: Dietary supplement: Whey protein

• Study Type: Interventional
• Enrollment (Actual): 40
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Netherlands
  • Limburg
    • Maastricht, Limburg, Netherlands, 6229ER
      • Maastricht University Medical Center+

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

1. In order to be eligible to participate in this study, a patient with CKD must meet all of the following criteria:

   • (e)glomerular filtration rate (GFR) <45 ml/min/1.73m2
   • Age: 18 - 80 y
   • Able to provide written informed consent

2. In order to be eligible to participate in this study, a healthy subject must meet all of the following criteria:

   • (e)GFR >60 ml/min/1.73m2 without albuminuria
   • Age: 18 - 80 y
   • Able to provide written informed consent

1. A potential subject with CKD who meets any of the following criteria will be excluded from participation in this study:

• Insulin-dependent diabetes mellitus or two or more oral glucose lowering medications
• Active inflammatory disease / malignancies
• Uncontrolled hypertension (>160/100mm Hg), unstable angina pectoris, or arrhythmia
• Pulmonary disease restricting exercise performance (e.g. COPD)
• A history of neuromuscular problems
• Cognitive Impairment
• Diagnosed GI tract diseases / dysphagia
• Allergies to milk proteins / Lactose intolerance
• Pregnancy
• Hospitalization <1 months prior to study period
• Participation in any structured exercise program
• Any medications known to affect protein metabolism (i.e. corticosteroids or prescription strength acne medications).
• Use of DOAC, vitamin-K-antagonist, or multiple anticoagulants.

• Dialysis treatment or previous kidney transplantation

  2. A potential healthy subject who meets any of the following criteria will be excluded from participation in this study:

• Insulin-dependent diabetes mellitus or two or more oral glucose lowering medications
• Active inflammatory disease / malignancies
• Uncontrolled hypertension (>160/100mm Hg), unstable angina pectoris, or arrhythmia
• Pulmonary disease restricting exercise performance (e.g. COPD)
• A history of neuromuscular problems
• Cognitive Impairment
• Diagnosed GI tract diseases / dysphagia
• Allergies to milk proteins / Lactose intolerance
• Pregnancy
• Hospitalization <1 months prior to study period
• Participation in any structured exercise program
• Any medications known to affect protein metabolism (i.e. corticosteroids or prescription strength acne medications).
• Use of DOAC, vitamin-K-antagonist, or multiple anticoagulants.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Habitual lifestyle period; All participants will be encouraged to keep their diet and physical activity similar to before the study period. Subjects will be asked to record their food intake and wear an Actical physical activity monitor for 3 days throughout the habitual lifestyle period (2 week days and 1 weekend day).; All participants will be asked to ingest 20 mL deuterated water and take a saliva sample daily
Experimental: Exercise training period; All participants will be encouraged to keep their diet and physical activity similar to before the study period. Subjects will be asked to record their food intake and wear an Actical physical activity monitor for 3 days throughout the exercise training period (2 week days and 1 weekend day).; Participants will be asked to ingest 20 mL deuterated water and take a saliva sample daily; Participants will visit the University three times with 2-day intervals (e.g. Monday-Wednesday-Friday) for an exercise training session as described in 5.6.; Following the training sessions, participants will be provided with a protein supplement as described in 5.7.; Before and after ingestion of the protein supplement, participants will be asked to fill in a gastrointestinal tolerance and palatability survey.	Dietary supplement: Whey protein; Throughout 1 week (either in week 1 or 2), all participants will perform a 1-week resistance type exercise-training program, consisting of two different exercises. Leg press and leg extension exercise will be performed on regular weightlifting machines (Technogym, Rotterdam) at 3 days during the 1-week period (e.g. Monday-Wednesday-Friday). During the resistance exercise training protocol, participants will continue their habitual diet as usual. However, patients with CKD will be provided with a protein supplement following the exercise sessions.; Other Names: Resistance exercise

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Muscle protein synthesis rates	Muscle protein synthesis rates as measured by the deuterated water method	1-week period

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Physical activity levels	as measured by accelerometry	1-week period
Dietary intake (energy/macronutrient)	as measured by dietary diaries	1-week period
Leg fat free mass	as measured by DEXA	Baseline
Body composition	as measured by BIA	Baseline
Type I and II skeletal muscle fiber size	of muscle biopsy of vastus lateralis	Baseline
Skeletal muscle mitochondrial bioenergetics	of muscle biopsy of vastus lateralis	Baseline
Muscle strength	1-RM max testing of leg press and leg extension	Baseline
Aerobic capacity	VO2-peak test on ergometer	Baseline

Collaborators and Investigators

• Sponsor: Maastricht University Medical Center
• Investigators: Principal Investigator: Luc JC van Loon, Prof. Dr., Maastricht University

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2023
• Primary Completion (Actual): December 2, 2024
• Study Completion (Actual): December 2, 2024

Study Registration Dates

• First Submitted: July 28, 2022
• First Submitted That Met QC Criteria: July 28, 2022
• First Posted (Actual): August 1, 2022

Study Record Updates

• Last Update Posted (Estimated): January 16, 2026
• Last Update Submitted That Met QC Criteria: January 15, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Urogenital Diseases; Neurologic Manifestations; Nervous System Diseases; Neuromuscular Manifestations; Male Urogenital Diseases; Pathological Conditions, Anatomical; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Atrophy; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Kidney Diseases; Muscular Atrophy; Amino Acids, Peptides, and Proteins; Proteins; Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena; Therapeutics; Physical Therapy Modalities; Food; Diet, Food, and Nutrition; Physiological Phenomena; Food and Beverages; Patient Care; Exercise Therapy; Rehabilitation; Aftercare; Continuity of Patient Care; Dairy Products; Physical Conditioning, Human; Exercise; Milk; Dietary Proteins; Milk Proteins; Animal Proteins, Dietary; Whey; Resistance Training; Whey Proteins
• Other Study ID Numbers: METC 22-032

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: Not yet determined

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No