A short-duration combined intervention of intravenous bolus amino acids and cycle ergometry, limited to the acute phase of critical illness, did not reduce muscle loss or improve muscle quality, strength, or physical capability.
Key Findings
Results
Muscle loss occurred significantly over time in critically ill patients regardless of intervention group.
Primary co-outcomes were changes in vastus lateralis myofiber cross-sectional area (from biopsies) and ultrasound-derived rectus femoris cross-sectional area
Measurements were taken between preintervention (day 2) and postintervention (day 8) time points
Biopsy outcome: P = 0.01; ultrasound outcome: P < 0.001
No significant differences between intervention and standard care groups for either primary outcome
Results
The intervention group received significantly more protein per day than the standard care group.
Standard of care participants received 1.23 ± 0.18 g/kg/day protein
Intervention participants received 1.57 ± 0.27 g/kg/day protein total
The intravenous amino acid supplement contributed 0.37 ± 0.05 g/kg/day of the intervention group's total protein intake
Both groups received standard care nutrition and mobilization as a baseline
Results
No significant differences between groups were observed in any secondary outcomes.
Secondary outcomes assessed included protein-to-DNA ratio, muscle echogenicity, whole-body phase angle, muscle strength (Medical Research Council sum score), and physical capability (6-min walk test)
No significant between-group differences were found for any of these measures
Analyses were conducted using mixed-model analysis of variance and least significant difference testing
Methods
The study enrolled 50 critically ill adult patients who were predominantly young and male.
50 patients were included in the randomized parallel-group trial
90% of participants were male
Mean age was 37 ± 12 years
Patients were admitted to the surgical intensive care unit of a tertiary hospital
The intervention was administered starting on days 3-4 for a mean of 6 days
Methods
The combined intervention consisted of a daily intravenous amino acid bolus paired with 45 minutes of cycle ergometry during the acute phase of critical illness.
Intervention began on days 3-4 of ICU admission
The mean intervention duration was 6 days
Cycle ergometry sessions lasted 45 minutes
The intervention was delivered on top of standard care nutrition and mobilization
Veldsman L, Richards G, Nel D, Kohn T, Blaauw R. (2026). Combined intravenous bolus amino acid supplementation and mobilization on early muscle loss in critically ill adults: A randomized controlled trial.. JPEN. Journal of parenteral and enteral nutrition. https://doi.org/10.1002/jpen.70041