This randomized controlled trial aims to evaluate the effects of velocity-based resistance training on renal function and metabolic health in kidney transplant recipients. Participants will be randomized into two groups performing resistance training at different execution velocities (maximal intended vs. submaximal controlled). The intervention will last 12 weeks and include multi-joint exercises (squat, bench press, military press). Primary outcomes include renal function (serum creatinine, eGFR, blood urea nitrogen, uric acid) and metabolic markers (HDL, triglycerides, glucose, waist circumference, blood pressure). Secondary outcomes include muscle strength, force-velocity profile, anthropometry, physical activity, fitness perception, and adherence to immunosuppressive medication.
This randomized controlled trial will examine the physiological and metabolic responses to different resistance training velocities in kidney transplant recipients. Participants will be randomized to perform either maximal-velocity or submaximal-velocity resistance exercises for 12 weeks. Each session will include multi-joint movements (bench press, squat, overhead press) using a Smith machine. Training loads will be individualized (20-60% 1RM) and monitored using a linear encoder to control velocity loss. Primary endpoints are renal function and metabolic health markers, while secondary outcomes include neuromuscular performance and adherence to immunosuppressive therapy. The study has received ethics approval from Fundación Universitaria del Área Andina (Acta 15, April 22, 2025).
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
SINGLE
Enrollment
12
A 12-week supervised resistance training program performed 3 sessions per week. Exercises will include bench press, squat, and shoulder press in Smith machine. Participants will execute each repetition at \~50% of maximal concentric velocity, with sets completed according to predetermined repetitions (20-30 depending on load, 20-60% 1RM).
A 12-week supervised resistance training program performed 3 sessions per week. Exercises will include bench press, squat, and shoulder press in Smith machine. Participants will execute each repetition at maximal concentric velocity, with sets terminated at 20% velocity loss. Training loads will increase progressively (20-60% 1RM).
Colombia
Bogotá, Bogota D.C., Colombia
RECRUITINGSerum creatinine (mg/dL) - change from baseline
Serum creatinine will be measured from venous blood samples processed in an external certified laboratory (IDIME, Bogotá). This parameter will serve as a biomarker of renal graft function.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
Estimated glomerular filtration rate (eGFR, mL/min/1.73 m²) - change from baseline
The estimated glomerular filtration rate (eGFR) will be calculated from serum creatinine using validated equations (CKD-EPI or MDRD). This measure will serve as the most sensitive indicator of renal graft function.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
Blood urea nitrogen (BUN, mg/dL) - change from baseline
Blood urea nitrogen will be measured to monitor renal clearance capacity and metabolic status.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
Serum Uric Acid (mg/dL)
Serum uric acid will be measured as a biomarker of renal excretory capacity and cardiovascular risk.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
HDL cholesterol (mg/dL) - change from baseline
HDL cholesterol will be measured as a protective lipid biomarker inversely associated with metabolic and cardiovascular risk.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
Triglycerides (mg/dL) - change from baseline
Serum triglycerides will be measured to evaluate metabolic health and risk of cardiovascular disease.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
Fasting glucose (mg/dL) - change from baseline
Fasting blood glucose will be measured through enzymatic methods to evaluate glycemic control.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
Waist circumference (cm) - change from baseline
Waist circumference will be measured at the narrowest point of the torso, midway between the lower margin of the ribs and the iliac crest, following ISAK recommendations. This anthropometric variable will serve as a key component of metabolic syndrome diagnosis.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
Metabolic Risk Index (z-score composite)
A composite metabolic risk index will be calculated from triglycerides, LDL, HDL, glucose, and systolic/diastolic blood pressure values. Each variable will be standardized as z-scores; HDL will be multiplied by -1 due to its inverse relationship with cardiovascular risk. The final score will be the sum of standardized values.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
Handgrip strength
Handgrip strength will be assessed using a digital dynamometer (Takei Scientific Instruments, Tokyo). Two trials per hand, best value recorded. This test reflects overall muscle strength.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
Body Composition (fat percent, muscle percent, visceral fat)
Body composition will be assessed using segmental bioelectrical impedance analysis (Tanita IRONMAN BC-1500). Measurements will include fat percentage, muscle percentage, and visceral fat.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
Force-Velocity Profile
:The force-velocity profile will be assessed using a linear encoder (T-Force) during three multi-joint exercises (bench press, squat, overhead press). The relationship between force and velocity will be calculated to estimate neuromuscular performance.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
Body Height (cm)
Body height will be measured with a digital stadiometer following the Frankfurt plane reference to ensure standardized posture.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
Relative Handgrip Strength (kg/kg body weight)
Relative handgrip strength will be calculated by dividing the maximum handgrip force by body weight to account for body size.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
Comorbidity and Immunosuppressive Therapy Questionnaire
A structured questionnaire will be used to record comorbidities and medication adherence. Adherence will be rated on a 5-point Likert scale (1 = never adherent, 5 = always adherent), where higher scores indicate better adherence.
Time frame: Baseline and week 13 (after completion of 12-week intervention)
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.