The effect of chronic soluble keratin supplementation in physically active individuals on body composition, blood parameters and cycling performance.
J Int Soc Sports Nutr
; 15(1): 47, 2018 Sep 27.
Article
em En
| MEDLINE
| ID: mdl-30261892
ABSTRACT
BACKGROUND:
Keratins are structural, thiol-rich proteins, which comprise 90% of total poultry feather weight. Their favourable amino acid profile suggests the potential for use as a protein source and ergogenic aid for endurance athletes, following treatment to increase digestibility. This study investigated whether 4 weeks of soluble keratin (KER) consumption (0.8 g/kg bodyweight/day) by 15 endurance-trained males would have favourable effects on body composition, blood and cardiorespiratory variables, and cycling performance, compared to casein protein (CAS).METHODS:
Supplementation was randomized, blinded and balanced, with a minimum eight-week washout period between trials. An exercise test to measure oxygen consumption during submaximal and maximal cycling exercise was completed at the start at and end of each intervention. Anthropometric (DEXA) and blood measures were made prior to and following each intervention period.RESULTS:
Total body mass and percentage body fat did not change significantly (p > 0.05). However, a significantly greater increase in bone-free lean mass (LM) occurred with KER compared to CAS (0.88 kg vs 0.07 kg; p < 0.05). While no change in LM was evident for the trunk and arms, leg LM increased (0.45 ± 0.54 kg; p = 0.006) from baseline with KER. KER was not associated with changes in blood parameters, oxygen consumption, or exercise performance (p > 0.05).CONCLUSIONS:
These data suggest that KER is not useful as an ergogenic aid for endurance athletes but may be a suitable protein supplement for maximizing increases in lean body mass.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Composição Corporal
/
Suplementos Nutricionais
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Desempenho Atlético
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Queratinas
Tipo de estudo:
Clinical_trials
Limite:
Adult
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Humans
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Male
Idioma:
En
Revista:
J Int Soc Sports Nutr
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Nova Zelândia
País de publicação:
EEUU
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ESTADOS UNIDOS
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ESTADOS UNIDOS DA AMERICA
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EUA
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UNITED STATES
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UNITED STATES OF AMERICA
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US
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USA