35g Pre-Bed Casein Protein, 1st Fair, Isocaloric High Protein (1.8g/kg) Comparison: No Extra Muscle Gain in Young Men

Using casein protein pre-bed can be useful but probably only for those of you who use it to up their total protein intake.

"Once Upon a Time..." It may sound like it, but it is a fact when I tell you that there was a time when bodybuilders got up at night to consume a protein shake. That's not just the exact opposite of today's lean gains physique athletes, it is also PM protein ingestion taken to the extreme. An extreme of which a bunch of studies investigating the effects of the ingestion of slow-digesting casein protein before bed suggests that - even if it works - it may be an unnecessary sleep-impairing hassle.

High-protein diets are much safer than some 'experts' say, but there are things to consider...

Practical Protein Oxidation 101

5x More Than the FDA Allows!

More Protein ≠ More Satiety

Satiety: Casein > Whey? Wrong!

Protein Timing DOES Matter!

High Protein not a Health Threat

For those who don't want to go to such extremes, a recent study by Jordan M. Joy (Joy 2018) could be of interest, the intent of authors from Texas was, after all, to conduct ...

"[...] the first longitudinal isonitrogenous, isocaloric, nighttime casein supplementation study investigating the impact on body weight (BW) and composition as well as strength and muscle hypertrophy when an impactful resistance training stimulus occurs earlier in the day" (Joy 2018).

Previous studies have focused on the beneficial effects of additional protein intakes pre-bed. Now, these studies were useful to establish that ...

• protein is digested and absorbed during sleep,  
• muscle and other tissues respond to hyperaminoacidemia during sleep by increasing muscle protein synthesis (MPS) when prior resistance exercise occurs in the evening 

In 2015, Snijders et al. (2015) conducted a study that supports both hypotheses. Over the course of 12-weeks, fourty-four young men (22 ± 1 y) were randomly assigned to a progressive, 12-wk resistance exercise training program. One group consumed a protein supplement containing 27.5 g of protein, 15 g of carbohydrate, and 0.1 g of fat every night before sleep. The other group received a noncaloric placebo... unfair? Well, I cannot deny that, but that's what you call a "proof of principle" study.

Figure 1: Predicted resting energy expenditure (REE, kJ/d) for 50 min the morning after night-time consumption of a single serving of whey protein (WP), casein protein (CP), maltodextrin (CHO) and a non-energetic placebo (PLA | Madzimam 2014).

Won't PM protein make you fat? The authors of the paper at hand already foresaw that you'd ask that and reference studies Ormsbee's group at the Florida State University conducted between 2014 and 2016 (Madzima 2014; Kinsey 2015 & 2016). While Madzima et al. (2014) were able to show a significant increase in resting energy expenditure of young, healthy, normal-weight men on the morning after ingesting ~30g of whey, casein, or carbohydrates compared to placebo (see Figure 1), it took another 2 years for a follow-up study to make it from the drawing board through data-analysis and peer-review into the August issue of Nutrients.

Said study confirms: There are no detrimental effects of pre-bed casein on glucose metabolism, resting energy expenditure, and appetite - even if the study subjects are hyperinsulemic obese men... that's good news in terms of fat gain, but bad news when it comes to the notion that the increased energy expenditure reported by Madzima et al. could help obese individuals lose weight... why? Well, as I wrote before: in the obese subjects of Kinsey 2016, it simply didn't occur.

Accordingly, the previous study/-ies left us with the important question whether any improvements in protein synthesis and lean mass were more than the mere result of the fact that the supplement group consumes 1.9g/kg and the control group only 1.3g/kg protein per day. Exactly this is where Joy et al.'s new study is coming in.

As discussed in the context of different studies, protein timing is a thing... one that probably matters much less than the average gymrat believes. For pre-bed-protein the situation does, however, look different than it does for the legendary post-workout window of opportunity, for which - in science-terms - a ton of research on its importance (or non-importance) for gains exists. For the previously hinted at reasons, this cannot be said of the pre-bed protein research where there's exactly one (the study at hand) fair comparison of post-workout vs. pre-bed protein...

Wait... post-workout vs. pre-bed that's unfair, too, isn't it?

It certainly depends on whether you are with Schoenfeld and Aragon when it comes to the (non-)importance of protein timing if you consider it a "fair" comparison if you have one group of healthy, recreationally active, 18–25-year-old males who have been engaged in regular exercise for the previous 1–3 years at a frequency of 2–5 days per week on night-time vs. post-exercise protein?

Figure 2: The study subjects consumed 1.8 g protein/kg BW inclusive of the casein supplement, and the remainder of calories were provided as 35% fat and 65% carbohydrate - the result is a macronutrient ratio of 28/52/20%.

A lot of strengths and one small weakness: DXA, body impedance and ultrasonography-determined (Logiq e, General Electric Corporation, Boston, MA) CSA of the rectus femoris and combined muscle thickness (MT) of the vastus lateralis and vastus intermedius = reliable data on potential benefits of pre-bed protein supplementation; trained (albeit only "recreationally") subjects = no newbie gains messing with the results; high standardization in terms of strength/performance testing = reliable data on potential performance benefits of pre-bed protein; reasonable, yet intense workout program (see Table 1) as one will see it done by trainees in the real-world = high probability to see similar results in real-world strength/hypertrophy training; dietary standardization, including a standardized total protein and total energy intake = any putative effect will actually be due to timing...

That's a pretty long list of strengths, isn't it? Well, there is also one shortcoming, namely the fact that only 13 subjects completed the entire 10 weeks study. In spite of that, the study at hand is a good example of the often falsely neglected 'null-result' studies that add important information to our understanding of optimal training and nutrition for body composition and performance.

In that, the term "post-exercise"-protein may be misleading, because Joy et al. had both groups consume 25g of whey protein immediately after their workouts. In the literal sense - that's the "post-exercise"-protein. The crucial timing difference, on the other hand, was introduced with 30g of micellar casein which were consumed (a) on top of the 25g of whey at (b) different timepoints. I've briefly corresponded with the authors about the casein timing issue because unlike pre-bed administration, the idea of having casein sometime later in the day is pretty vague. Here's what Jordon Joy told me:

"For the day-time-group, they drank the casein at least 3 hours removed from exercise. Could have been before or after (usually depending on their training time) and they could not have it within 6 hours before bed" (Joy, private communication).

This is interesting as it introduces the possibility that the subjects in the day-time-group came to the gym with elevated amino acid levels. After all, Lacroix et al. were able to show that the serum amino acid levels remain elevated for 5+h in response to the ingestion of a micellar casein protein (Lacroix 2006) - a practice of which Tipton et al. show that it is at least as effective as the ingestion of protein after workouts (unlike in the study at hand, Tipton et al. used whey protein administered immediately before and after workouts in elderly subjects, though - the elevation of amino acids was thus significantly higher and age-related reductions in MPS may figure, as well | Tipton 2006). With that being said, the authors told me that the majority consumed the casein after workouts. 

Weeks 1–5
Monday		Tuesday		Thursday		Friday
Lower Hypertrophy		Upper Hypertrophy		Lower Strength		Upper Strength
Leg Press	5 × 6–15	Bench Press	5 × 6–15	Leg Press	5 × 1–5	Bench Press	5 × 1–5
SS Box Squat	4 × 6–15	Decline Press	3 × 6–15	Hack Squat	3 × 1–5	DB Press	3 × 3–8
Hyperextension	3 × 6–15	Incline Flye	3 × 6–15	Lunge	3 × 3–8	Shoulder Press	3 × 3–8
1-Leg Extension	3 × 6–15	Machine Shoulder Press	3 × 6–15	1-Leg Extension	3 × 6–15	Chest Supported Row	3 × 3–8
2-Leg Curl	3 × 6–15	Lateral Raise	3 × 6–15	2-Leg Curl	3 × 6–15	Pulldown	3 × 3–8
Calf Press	3 × 6–15	Low Cable Row	5 × 6–15	Leg Raise	3 × 10–20	YTWL	3 × 6
1-Tricep Extension	3 × 6–15	Pulldown	3 × 6–15
2-Bicep Curl	3 × 6–15	1-Cable High Row	3 × 6–15
Cable Abdominal Crunch	3 × 10–20	2-Rear Delt Flye	3 × 6–15
Weeks 6–10
Monday		Tuesday		Thursday		Friday
Lower Hypertrophy		Upper Hypertrophy		Lower Strength		Upper Strength
Leg Press	5 × 6–15	Bench Press	5 × 6–15	Leg Press	5 × 1–5	Bench Press	5 × 1–5
Front Squat	4 × 6–15	Incline Press	3 × 6–15	SS Box Squat	3 × 1–5	Pause Press	3 × 1–5
V-Squat Good Morning	3 × 6–15	Decline DB Press	3 × 6–15	DB Lunge	3 × 3–8	DB Shoulder Press	3 × 3–8
1-Leg Extension	3 × 6–15	Shoulder Press	3 × 6–15	1-Leg Extension	3 × 6–15	Cable Low Row	3 × 3–8
2-Leg Curl	3 × 6–15	Cable+DB Lateral Raise	3 × 6–15	2-Leg Curl	3 × 6–15	Pulldown	3 × 3–8
Calf Press	3 × 6–15	Chest Supported Row	5 × 6–15	Leg Raise	3 × 10–20	YTWL	3 × 6
1-Supine Tricep Extension	3 × 6–15	Pulldown	3 × 6–15
2-Preacher Curl	3 × 6–15	1-Cable High Row	3 × 6–15
Abdominal Crunch	3 × 10–20	2-Rear Delt Flye	3 × 6–15

Weeks 1–5

Monday

Tuesday

Thursday

Friday

Lower Hypertrophy

Upper Hypertrophy

Lower Strength

Upper Strength

Leg Press

5 × 6–15

Bench Press

5 × 6–15

Leg Press

5 × 1–5

Bench Press

5 × 1–5

SS Box Squat

4 × 6–15

Decline Press

3 × 6–15

Hack Squat

3 × 1–5

DB Press

3 × 3–8

Hyperextension

3 × 6–15

Incline Flye

3 × 6–15

Lunge

3 × 3–8

Shoulder Press

3 × 3–8

1-Leg Extension

3 × 6–15

Machine Shoulder Press

3 × 6–15

1-Leg Extension

3 × 6–15

Chest Supported Row

3 × 3–8

2-Leg Curl

3 × 6–15

Lateral Raise

3 × 6–15

2-Leg Curl

3 × 6–15

Pulldown

3 × 3–8

Calf Press

3 × 6–15

Low Cable Row

5 × 6–15

Leg Raise

3 × 10–20

YTWL

3 × 6

1-Tricep Extension

3 × 6–15

Pulldown

3 × 6–15

2-Bicep Curl

3 × 6–15

1-Cable High Row

3 × 6–15

Cable Abdominal Crunch

3 × 10–20

2-Rear Delt Flye

3 × 6–15

Weeks 6–10

Monday

Tuesday

Thursday

Friday

Lower Hypertrophy

Upper Hypertrophy

Lower Strength

Upper Strength

Leg Press

5 × 6–15

Bench Press

5 × 6–15

Leg Press

5 × 1–5

Bench Press

5 × 1–5

Front Squat

4 × 6–15

Incline Press

3 × 6–15

SS Box Squat

3 × 1–5

Pause Press

3 × 1–5

V-Squat Good Morning

3 × 6–15

Decline DB Press

3 × 6–15

DB Lunge

3 × 3–8

DB Shoulder Press

3 × 3–8

1-Leg Extension

3 × 6–15

Shoulder Press

3 × 6–15

1-Leg Extension

3 × 6–15

Cable Low Row

3 × 3–8

2-Leg Curl

3 × 6–15

Cable+DB Lateral Raise

3 × 6–15

2-Leg Curl

3 × 6–15

Pulldown

3 × 3–8

Calf Press

3 × 6–15

Chest Supported Row

5 × 6–15

Leg Raise

3 × 10–20

YTWL

3 × 6

1-Supine Tricep Extension

3 × 6–15

Pulldown

3 × 6–15

2-Preacher Curl

3 × 6–15

1-Cable High Row

3 × 6–15

Abdominal Crunch

3 × 10–20

2-Rear Delt Flye

3 × 6–15

Table 1: Overview of the workout program Joy et al. prescribed (Joy 2018).

Even if we assumed that this form of pre-workout (slow digesting) protein supplementation was relevant, it is thus unlikely to have had an effect in the study at hand. Accordingly, any beneficial/detrimental inter-group differences should - as the authors planned - be a consequence of nighttime protein ingestion in response to a realistic hypertrophy + strength workout (see Table 1) in what you can describe as otherwise "optimal" protein-anabolic conditions.

Figure 3: Changes in body composition over the 10-week study in the nighttime and daytime protein group (Joy 2018).

The scientists' data analyses using repeated measures ANOVA with Bonferroni post-hoc (alpha was set at p < 0.05), do yet show: there is no such effect. In fact, if anything, the daytime protein administration seems to have a non-significant edge when it comes to the extent of the significant main effect of time (p < 0.05).

No effect was observed for the weekly averages of DOMS and RPE, either. Things look only marginally different for the performance measures. No significant inter-group differences... with one exception: The peak force (PF) during vertical jumps decreased by − 249 ± 386N while it increased by 445 ± 602 N in the daytime supplementation arm of the study.

In 2012 a study by Res et al. rekindled the interest in pre-bed casein | more.

Bottom line: Within the limits of this (small-scale N=13) 10-week study the timed ingestion of micellar casein before bed doesn't offer significant advantages in terms of either changes in body composition or performance markers. In fact, the "daytime administration" group seems to have seen greater benefits from the workouts... non-significantly greater, that is. Eventually, the study at hand does, therefore, confirm the notion that timing doesn't really matter as long as a high enough protein intake (here: 1.8 g protein/kg body weight) is achieved.

This doesn't mean that the issue is settled once and for all, though. In fact, an even longer-term and (more importantly) larger-scale follow-up would be great... maybe one in which Joy et al. investigate a hypothesis they present in the discussion of the results: "[...] it could be possible for DT casein consumption to create an 'elevated baseline' for hyperaminoacidemia, thereby reducing the absolute amount of dietary protein necessary to maximize protein synthesis in meals consumed during the 6–7 h postprandial period following casein supplementation". To me, that sounds logical and it should be possible to test it by repeated pre-post-meal blood draws and subsequent analyses of the amino acid content of the subjects' blood - ideally, obviously, these results would be corroborated by concomitant changes in muscle protein synthesis in after meals | Comment!

References:

• Joy, Jordan M., et al. "Daytime and nighttime casein supplements similarly increase muscle size and strength in response to resistance training earlier in the day: a preliminary investigation." Journal of the International Society of Sports Nutrition 15.1 (2018): 24.
• Kinsey, Amber W., and Michael J. Ormsbee. "The health impact of nighttime eating: old and new perspectives." Nutrients 7.4 (2015): 2648-2662.
• Kinsey, Amber W., et al. "The effect of casein protein prior to sleep on fat metabolism in obese men." Nutrients 8.8 (2016): 452.
• Lacroix, Magali, et al. "Compared with casein or total milk protein, digestion of milk soluble proteins is too rapid to sustain the anabolic postprandial amino acid requirement–." The American journal of clinical nutrition 84.5 (2006): 1070-1079.
• Madzima, Takudzwa A., et al. "Night-time consumption of protein or carbohydrate results in increased morning resting energy expenditure in active college-aged men." British journal of nutrition 111.1 (2014): 71-77.
• Snijders T, Res PT, Smeets JS, van Vliet S, van Kranenburg J, Maase K, Kies AK, Verdijk LB, van Loon LJ. Protein ingestion before sleep increases muscle mass and strength gains during prolonged resistance-type exercise training in healthy young men. J Nutr. 2015;145:1178–84.
• Tipton, Kevin D., et al. "Stimulation of net muscle protein synthesis by whey protein ingestion before and after exercise." American Journal of Physiology-Endocrinology and Metabolism 292.1 (2007): E71-E76.