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Effects of enzymatically modified isoquercitrin in supplementary protein powder on athlete body composition: a randomized, placebo-controlled, double-blind trial

Naomi Omi, Hideki Shiba, Eisaku Nishimura, Sakuka Tsukamoto, Hiroko Maruki-Uchida, Masaya Oda, Minoru Morita
Journal of the International Society of Sports Nutrition 2019 16(1):39

Bibliography

PubMed
PMID 31500646
PubMed Central
PMC6734270
DOI
10.1186/s12970-019-0303-x
Funding
Indexed funding or support includes MORINAGA. The source provides grant details and contributor roles.
Competing interests
Reported disclosure: This research received financial support from MORINAGA & CO., Ltd. (Tokyo, Japan). EN, ST, HM-U, and MM are employees of MORINAGA & CO., Ltd. The other authors declare that they have no competing interests.

Study snapshot

DesignRandomized double-blind placebo-controlled protein-supplement trial
ModelHuman intervention research
Sample40 male American-football players enrolled; 39 reported across treatment arms
InterventionWhey protein with or without enzymatically modified isoquercitrin
Duration4 months, 6 days/week
EndpointsExercise performance or recovery

What the study showed, in plain terms

Published in 2019, this source examined exercise and recovery. Design: Randomized double-blind placebo-controlled protein-supplement trial. Sample/model: 40 male American-football players enrolled; 39 reported across treatment arms. The exposure or intervention was Whey protein with or without enzymatically modified isoquercitrin. Follow-up or treatment period: 4 months, 6 days/week.

Lower-limb fat-free and muscle-mass changes favored the EMIQ protein group. Overall body and lean-mass outcomes did not differ.

Small, specific athlete population and combined protein intervention. The linked correction should be read with the original report.

Continue with Quercetin Data Center

For topic-level interpretation, read Quercetin for Exercise: Performance, Recovery and Muscle. This is a related guide; the citation panel separately identifies articles that directly cite this paper.

Key findings

  • Lower-limb fat-free and muscle-mass changes favored the EMIQ protein group.
  • Overall body and lean-mass outcomes did not differ.
  • The recorded outcome domains were Exercise performance or recovery.
  • The result applies to the tested exposure: Whey protein with or without enzymatically modified isoquercitrin; 4 months, 6 days/week.

What this study can and cannot tell us

  • Small, specific athlete population and combined protein intervention. The linked correction should be read with the original report.
  • An individual controlled trial must be interpreted alongside its comparator, sample size, endpoint selection and independent replication. It does not validate a different commercial formulation or a general longevity claim.
  • Source basis: Source check: accessible full text and indexed metadata. Missing method details, funding information or participant denominators are not inferred.

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Citation network

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Dr. Khaled Mahmoud, MBBChCritical Care Medicine, Longevity Science & Editorial Direction Dr. Amr Yasser, PhDCardiometabolic, Musculoskeletal, Gut & Bioavailability Dr. Abdulla Mostafa, PhDCellular Senescence, Neurological, Mitochondrial & Brain-Ageing Biology