Institute of Sports Sciences and Medicine, Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA.
Korey Stringer Institute, Department of Kinesiology, University of Connecticut, Storrs, CT, USA.
J Nutr. 2020 Jan 1;150(1):47-54. doi: 10.1093/jn/nxz186.
To date, no studies have directly compared the differences between presleep and daytime protein (PRO) consumption on localized and systemic fat metabolism in active women.
The purpose of this study was to assess the effects of presleep compared with daytime PRO supplementation on subcutaneous abdominal adipose tissue (SCAAT) lipolysis and whole-body substrate utilization in women.
Thirteen young (mean ± SE age: 22 ± 1 y; BMI: 24.3 ± 0.8 kg/m2), resistance-trained [1 repetition maximum (1RM) squat percentage of body weight: 135% ± 6%; 1RM bench press percentage of body weight: 82% ± 4%] women volunteered. On overnight experimental visits, participants performed full-body resistance exercise (RE; 65% 1RM) and were randomly assigned to consume either daytime PRO (PRO, 30 g casein) 30 min post-RE and presleep (30 min before bed) noncaloric, sensory-matched placebo (PLA, 0 g casein) (PRO-PLA), or the opposite (PLA-PRO), switching the order of the supplements on the following visit. SCAAT lipolysis, resting metabolism (indirect calorimetry), and plasma biomarkers (glucose, insulin, nonesterified fatty acids, glycerol) were measured at baseline, overnight, and the next morning.
There were no differences in overnight SCAAT lipolysis between conditions indicated by interstitial glycerol concentrations (PRO-PLA: baseline, 669 ± 137; next morning, 321 ± 77.1; PLA-PRO: baseline, 524 ± 109; next morning, 333 ± 68.0 μM), fat oxidation (PRO-PLA: baseline, 5.70 ± 0.35; next morning, 5.00 ± 0.28; PLA-PRO: baseline, 6.59 ± 0.32; next morning, 5.44 ± 0.27 g/min), or any other measure.
There was no difference between the effects of daytime and presleep PRO supplementation on SCAAT lipolysis or whole-body substrate utilization in resistance-trained women. Presleep PRO is a viable option for increasing PRO consumption in resistance-trained women because it does not blunt overnight lipolysis, and will therefore likely not lead to increases in subcutaneous abdominal fat.This trial was registered at clinicaltrials.gov as NCT03573687.
迄今为止，尚无研究直接比较活跃女性的睡前和日间蛋白质（PRO）摄入对局部和全身脂肪代谢的差异。
本研究旨在评估与日间 PRO 补充相比，睡前 PRO 补充对女性腹部皮下脂肪组织（SCAAT）脂肪分解和全身底物利用的影响。
13 名年轻（平均±SE 年龄：22±1 岁；BMI：24.3±0.8kg/m2）、接受过抗阻力训练的女性（1 次重复最大（1RM）深蹲体重百分比：135%±6%；1RM 卧推体重百分比：82%±4%）自愿参加。在过夜的实验访问中，参与者进行了全身抗阻力运动（RE；65%1RM），并随机分配到以下三种情况中的一种：在 RE 后 30 分钟和睡前（睡前 30 分钟）摄入日间 PRO（PRO，30g 乳清蛋白）和非热量、感官匹配的安慰剂（PLA，0g 乳清蛋白）（PRO-PLA）；或相反的情况（PLA-PRO），在下一次访问时交换补充剂的顺序。在基线、过夜和次日早晨测量腹部皮下脂肪组织的脂肪分解、静息代谢（间接测热法）和血浆生物标志物（血糖、胰岛素、非酯化脂肪酸、甘油）。
提示间质甘油浓度（PRO-PLA：基线，669±137；次日早晨，321±77.1；PLA-PRO：基线，524±109；次日早晨，333±68.0μM）、脂肪氧化（PRO-PLA：基线，5.70±0.35；次日早晨，5.00±0.28；PLA-PRO：基线，6.59±0.32；次日早晨，5.44±0.27g/min）或其他任何指标，在夜间的腹部皮下脂肪组织脂肪分解或全身底物利用方面，日间和睡前 PRO 补充之间没有差异。睡前 PRO 是增加抗阻力训练女性 PRO 摄入量的可行选择，因为它不会抑制夜间脂肪分解，因此不太可能导致腹部皮下脂肪增加。本试验在 clinicaltrials.gov 上注册为 NCT03573687。
