Details

Autor(en) / Beteiligte

• Wooding, Denise J
• Packer, Jeff E
• Kato, Hiroyuki
• West, Daniel W.D
• Courtney-Martin, Glenda
• Pencharz, Paul B
• Moore, Daniel R

Titel

Increased Protein Requirements in Female Athletes after Variable-Intensity Exercise

Ist Teil von

• Medicine and science in sports and exercise, 2017-11, Vol.49 (11), p.2297-2304

Ort / Verlag

United States: American College of Sports Medicine

Erscheinungsjahr

2017

Quelle

Journals@Ovid

Beschreibungen/Notizen

• PURPOSEProtein requirements are primarily studied in the context of resistance or endurance exercise with little research devoted to variable-intensity intermittent exercise characteristic of many team sports. Further, female populations are underrepresented in dietary sports science studies. We aimed to determine a dietary protein requirement in active females performing variable-intensity intermittent exercise using the indicator amino acid oxidation (IAAO) method. We hypothesized that these requirements would be greater than current IAAO-derived estimates in non-active adult males. METHODSSix females (21.2 ± 0.8 y, 68.8 ± 4.1 kg, 47.1 ± 1.2 ml O2⋅kg⋅min; mean ± SE) completed 5-7 metabolic trials during the luteal phase of the menstrual cycle. Participants performed a modified Loughborough Intermittent Shuttle Test prior to consuming 8 hourly mixed meals providing the test protein intake (0.2-2.66 g⋅kg⋅d), 6 g⋅kg⋅d carbohydrate, and sufficient energy for resting and exercise-induced energy expenditure. Protein was provided as crystalline amino acids modeling egg protein with [C]phenylalanine as the indicator amino acid. Phenylalanine turnover (Q) was determined from urinary [C]phenylalanine enrichment. Breath CO2 excretion (FCO2) was analyzed using mixed effects bi-phase linear regression with the breakpoint and upper 95% CI approximating the estimated average requirement (EAR) and recommended dietary allowance (RDA), respectively. RESULTSProtein intake had no effect on Q (68.7 ± 7.3 μmol⋅kg⋅h; mean ± SE). FCO2 displayed a robust bi-phase response (R = 0.66) with an EAR of 1.41 g⋅kg⋅dand RDA of 1.71 g⋅kg⋅d. CONCLUSIONSThe protein requirement estimate of 1.41and 1.71 g⋅kg⋅d for females performing variable-intensity intermittent exercise is greater than the IAAO-derived estimates of adult males (0.93 and 1.2 g⋅kg⋅d) and at the upper range of the ACSM athlete recommendations (1.2-2.0 g⋅kg⋅d).