Johnson Nathaniel R, Kotarsky Christopher J, Mahoney Sean J, Sawyer Bailee C, Stone Kara A, Byun Wonwoo, Hackney Kyle J, Mitchell Steven, Stastny Sherri N
Department of Health, Nutrition, and Exercise Sciences, North Dakota State University, Fargo, ND, USA.
Department of Health and Human Physiological Sciences, Skidmore College, Saratoga Springs, NY, USA.
Nutr Metab Insights. 2022 Jun 16;15:11786388221101829. doi: 10.1177/11786388221101829. eCollection 2022.
Evenness of protein intake is associated with increased lean mass, but its relationship with muscle strength and performance is uncertain.
We determined the association of evenness of protein intake with lean mass, muscle strength and endurance, and functional ability.
This was a cross-sectional study.
Data were collected at a research university in the upper midwestern United States.
One hundred ninety-two healthy women, aged 18 to 79 years, mean ± SEM 41.9 ± 1.3, completed the study.
Dietary intake was assessed using 3-day food diaries verified with food frequency questionnaires. To assess evenness of protein intake, the day was divided into 3 periods: waking to 11:30, 11:31 to 16:30, and after 16:30. Lean mass was measured with dual energy X-ray absorptiometry. Lower-body muscle strength and endurance were determined using isokinetic dynamometry. Upper-body muscle strength was maximal handgrip strength. Functional ability was assessed using 6-m gait speed and 30-second chair stand tests. Accelerometry measured physical activity.
Intakes of 25 g or more of protein at 1 or more of the 3 periods was positively associated with lean mass (β ± S.E.; 1.067 ± 0.273 kg, < .001) and upper-body (3.274 ± 0.737 kg, < .001) and lower-body strength (22.858 ± 7.918 Nm, = .004) when controlling for age, body mass index, physical activity, and energy and protein intakes. Consuming at least 0.24 g/kg/period for those under 60 years and 0.4 g/kg/period for those 60 years and older was related to lean mass (0.754 ± 0.244 kg, = .002), upper-body strength (2.451 ± 0.658 kg, < .001), and lower-body endurance (184.852 ± 77.185 J, = .018), controlling for the same variables.
Evenness of protein intake is related to lean mass, muscle strength, and muscular endurance in women. Spreading protein intake throughout the day maximizes the anabolic response to dietary protein, benefiting muscle mass and performance.
蛋白质摄入的均匀性与瘦体重增加相关，但其与肌肉力量和表现的关系尚不确定。
我们确定了蛋白质摄入均匀性与瘦体重、肌肉力量和耐力以及功能能力之间的关联。
这是一项横断面研究。
数据收集于美国中西部上游的一所研究型大学。
192名年龄在18至79岁之间的健康女性完成了该研究，平均年龄±标准误为41.9±1.3岁。
使用经食物频率问卷验证的3天食物日记评估饮食摄入量。为评估蛋白质摄入的均匀性，将一天分为3个时间段：醒来至11:30、11:31至16:30以及16:30之后。使用双能X线吸收法测量瘦体重。使用等速测力法测定下肢肌肉力量和耐力。上肢肌肉力量为最大握力。使用6米步行速度和30秒椅子站立测试评估功能能力。通过加速度计测量身体活动。
在控制年龄、体重指数、身体活动以及能量和蛋白质摄入量后，在3个时间段中的1个或更多时间段摄入25克或更多蛋白质与瘦体重（β±标准误；1.067±0.273千克，P<0.001）、上肢（3.274±0.737千克，P<0.001）和下肢力量（22.858±7.918牛米，P=0.004）呈正相关。对于60岁以下的人，每时间段摄入至少0.24克/千克，对于60岁及以上的人，每时间段摄入至少0.4克/千克，在控制相同变量后，与瘦体重（0.754±0.244千克，P=0.002）、上肢力量（2.451±0.658千克，P<0.001）和下肢耐力（184.852±77.185焦耳，P=0.018）相关。
蛋白质摄入的均匀性与女性的瘦体重、肌肉力量和肌肉耐力有关。将蛋白质摄入分散在一天中可使对膳食蛋白质的合成代谢反应最大化，有益于肌肉量和表现。
