Protein intake distribution pattern does not affect anabolic response, lean body mass, muscle strength or function over 8 weeks in older adults: A randomized-controlled trial.
In our recent acute metabolic study, we found no differences in the anabolic response to differing patterns of dietary protein intake. To confirm this in a chronic study, we investigated the effects of protein distribution pattern on functional outcomes and protein kinetics in older adults over 8 weeks.



To determine chronic effects of protein intake pattern at 1.1 g protein/kg/day in mixed meals on lean body mass (LBM), functional outcomes, whole body protein kinetics and muscle protein fractional synthesis rate (MPS) over 8-week respective dietary intervention, fourteen older subjects were randomly divided into either EVEN or UNVEN group. The UNEVEN group (n = 7) consumed the majority of dietary protein with dinner (UNEVEN, 15/20/65%; breakfast, lunch, dinner), while the EVEN group (n = 7) consumed dietary protein evenly throughout the day (EVEN: 33/33/33%).



We found no significant differences in LBM, muscle strength, and other functional outcomes between EVEN and UNEVEN before and after 8-week intervention. Consistent with these functional outcomes, we did not find significant differences in the 20-h integrated whole body protein kinetics [net protein balance (NB), protein synthesis (PS), and breakdown (PB)] above basal states and MPS between EVEN and UNEVEN intake patterns.



We conclude that over an 8-week intervention period, the protein intake distribution pattern in mixed meals does not play an important role in determining anabolic response, muscle strength, or functional outcomes. This trial is registered at https://ClinicalTrials.gov as NCT02787889.
Department of Geriatrics, Center for Translational Research in Aging and Longevity, Donald W. Reynolds Institute on Aging, University of Arkansas for Medical Sciences, Little Rock, AR, USA; Department of Molecular Medicine, Lee Gil Ya Cancer and Diabetes Institute Gachon University School of Medicine, Incheon, Republic of Korea. Electronic address: iykim@gachon.ac.kr.
Il-Young
IY
Kim
Department of Geriatrics, Center for Translational Research in Aging and Longevity, Donald W. Reynolds Institute on Aging, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
Scott
S
Schutzler
College of Medicine Biostatistics, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
Amy M
AM
Schrader
College of Medicine Biostatistics, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
Horace J
HJ
Spencer
Department of Geriatrics, Center for Translational Research in Aging and Longevity, Donald W. Reynolds Institute on Aging, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
Gohar
G
Azhar
Department of Geriatrics, Center for Translational Research in Aging and Longevity, Donald W. Reynolds Institute on Aging, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
Robert R
RR
Wolfe
Department of Geriatrics, Center for Translational Research in Aging and Longevity, Donald W. Reynolds Institute on Aging, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
Arny A
AA
Ferrando
D000368:Aged; D001823:Body Composition / Q000502:physiology*; D015992:Body Mass Index; D004044:Dietary Proteins / Q000008:administration & dosage*; D005247:Feeding Behavior / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D062407:Meals / Q000502:physiology*; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D014176:Protein Biosynthesis / Q000502:physiology*
D004044:Dietary Proteins
Aging; Essential amino acids; Protein turnover; Sarcopenia; Stable isotope tracer