Abstract
The purpose of the present study was to assess the acute effects of pre-sleep consumption of isocaloric casein protein (CP), CP and whey protein (BLEND), or non-caloric control (CTRL) at a dose relative to lean body mass (LBM) on recovery following an evening lower-body resistance exercise (RE) bout. Fifteen active and previously resistance-trained males (age: 21 ± 1 years, body fat: 14.2 ± 2.7%) participated in this randomized, single-blind, crossover study. Participants performed an evening lower-body RE bout and were provided with 0.4 g/kg/LBM of whey protein (WP) supplement post-RE. A single dose of 0.6 g/kg/LBM of CP, 0.4 g/kg/LBM of CP and 0.2 g/kg/LBM WP (BLEND), or CTRL was consumed 30 min prior to sleep. Measurements of perceived recovery (visual analogue scales (VAS) for recovery, soreness, and fatigue), appetite (VAS for hunger, satiety, and desire to eat), as well as pressure-pain threshold (dolorimeter), average power, and peak torque (isokinetic dynamometry) of the right thigh muscles were assessed the following morning. Main effects of time were seen for all recovery variables (perceived recovery: F2,28 = 96.753, p < 0.001, hp2 = 0.874; perceived fatigue: F2,28 = 76.775, p < 0.001; hp2 = 0.846; perceived soreness: F2,28 = 111.967, p < 0.001; hp2 = 0.889). A main effect of supplement was only seen for perceived recovery (F2,28 = 4.869; p = 0.015; hp2 = 0.258), with recovery being 6.10 ± 2.58 mm greater in CP vs. BLEND (p = 0.033) and 7.51 ± 2.28 mm greater in CP than CTRL (p = 0.005). No main effects of supplement were seen in measures of perceived soreness, or fatigue (F2,28 ≤ 2.291; p > 0.120; hp2 ≤ 0.141). No differences between supplements were found in perceived next-morning hunger (p = 0.06), satiety (p ≥ 0.227), or desire to eat (p = 0.528). Main effects of supplement were seen between BLEND and CP vs. CTRL for measures of pain-pressure threshold at the rectus femoris (F2,28 = 9.377; p = 0.001; hp2 = 0.401), the vastus lateralis (F2,28 = 10.887; p < 0.001; hp2 = 0.437), and the vastus medialis (F2,28 = 12.113, p < 0.001; hp2 = 0.464). Values of peak torque and average power were similar between all supplement groups at 60°/sec (F1.309,18.327 ≤ 1.994; p ≥ 0.173; hp2 ≤ 0.125), 180°/s (F2,28 ≤ 1.221; p ≥ 0.310; hp2 ≤ 0.080), and 300°/sec (F2,28 ≤ 2.854; p ≥ 0.074; hp2 ≤ 0.169). Pre-sleep consumption of CP and BLEND at a dose relative to LBM may enhance perceived overnight recovery to a greater extent than CTRL as a result of less muscle soreness the following morning after an acute evening RE bout.
Highlights
In the last few years, nutrient timing research has recognized the positive physiological benefits of pre-sleep consumption of protein within 30 min of sleep [1,2,3,4,5]
There were no statistically significant differences in total volume load performed by participants across supplement groups (p > 0.05)
Analysis of dietary logs revealed that participants in the CTRL condition consumed an average of 1887 ± 409 kcals (107 ± 41 g of protein, 202 ± 45 g of carbohydrates, 72 ± 30 g of fat), participants in the BLEND condition consumed an average of 1802 ± 453 kcals (105 ± 34 g of protein, 193 ± 70 g of carbohydrates, 68 ± 22 g of fat), and participants in the CP condition consumed an average of 1696 ± 404 kcal (108 ± 35 g of protein, 193 ± 70 g of carbohydrates, 68 ± 34 g of fat)
Summary
In the last few years, nutrient timing research has recognized the positive physiological benefits of pre-sleep consumption of protein within 30 min of sleep [1,2,3,4,5]. It has been established that active individuals should aim to increase the traditional recommended daily allowance of 0.8 g/kg/day [10] to about 1.4–2.0 g protein/kg/day for positive muscle protein balance [11] This daily amount of protein could be attained through the consumption of whole foods (i.e., chicken, fish, black beans, etc.), it may not be convenient due to meal preparation time, timing of exercise, or athletic practices. For this reason, protein-rich supplements consumed in addition to whole foods are a common strategy used by several populations, including active individuals, to reach the daily recommended values of protein intake [6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
