Effect of protein-supplement timing on strength, power, and body-composition changes in resistance-trained men.
The effect of 10 wk of protein-supplement timing on strength, power, and body composition was examined in 33 resistance-trained men. Participants were randomly assigned to a protein supplement either provided in the morning and evening (n = 13) or provided immediately before and immediately after workouts (n = 13). In addition, 7 participants agreed to serve as a control group and did not use any protein or other nutritional supplement. During each testing session participants were assessed for strength (one-repetition-maximum [1RM] bench press and squat), power (5 repetitions performed at 80% of 1RM in both the bench press and the squat), and body composition. A significant main effect for all 3 groups in strength improvement was seen in 1RM bench press (120.6 +/- 20.5 kg vs. 125.4 +/- 16.7 at Week 0 and Week 10 testing, respectively) and 1RM squat (154.5 +/- 28.4 kg vs. 169.0 +/- 25.5 at Week 0 and Week 10 testing, respectively). However, no significant between-groups interactions were seen in 1RM squat or 1RM bench press. Significant main effects were also seen in both upper and lower body peak and mean power, but no significant differences were seen between groups. No changes in body mass or percent body fat were seen in any of the groups. Results indicate that the time of protein-supplement ingestion in resistance-trained athletes during a 10-wk training program does not provide any added benefit to strength, power, or body-composition changes.
8 comments:
Nice article....
I have tried to tell some people about many studies like this one. The timing of protein ingestion is just not that important. Just as long as you get some in during the day, I agree that there won't be that much noticeable difference.
Nutrients are absorbed up to 24 hours post workout...another study I have read.
I get to laugh at my gym seeing guys drink protein drinks as they workout....too funny.
Dr. John
The question I have is did the protein supplement include carbs?
I wasn't able to access the full text, but I read the main abstract differently than you did in your summary.
"A significant main effect for all 3 groups in strength improvement was seen in 1RM bench press (120.6 +/- 20.5 kg vs. 125.4 +/- 16.7 at Week 0 and Week 10 testing, respectively) and 1RM squat (154.5 +/- 28.4 kg vs. 169.0 +/- 25.5 at Week 0 and Week 10 testing, respectively). "
The three groups are shakes far from training, near to training, and no supplements. "All 3 groups" increased strength, which means even the group taking no protein increased strength. With only 26 people taking protein and 7 not taking protein, this study was not able to detect a difference between those who take protein and those who do not.
i was always wondering if i could just eat more eggs or meat instead of protein supplements?
Jeremy - you are right of course. Thanks for pointing that out.
Anon - I'd always favour real food over supplements.
Full text link here:
http://forum.bodybuilding.com/showthread.php?t=116038351
"In conclusion, results of this study do not support the hypothesis that protein timing provides a significant benefit to lean body mass, strength, and power improvements in experienced resistance-trained athletes. However, considering
the relatively low carbohydrate content of the supplement and the low daily caloric intake of the participants, these results should be interpreted specifically to the
parameters measured"
but! @Jeremy,
"However, the results of this
study are also consistent with previous studies that demonstrated a trend toward greater strength improvements in resistance-trained participants with a daily protein intake greater than recommended levels for strength and power athletes (Hoffman et al., 2006). Although no significant differences were seen in comparisons between groups on strength and power performance, significant improvements in upper body strength and lower body power performance were seen in pre–post and a.m./p.m. only."
In other words, protein timing didn't seem to matter for these college-aged experienced lifters, but there were some improvements in strength that were observed only in the participants that took supplements (pre-post and a.m./p.m.).
@Greg "In the current study, the ratio of protein to carbohydrate was 21:1"
PS, it really helps to read the full text of an article before drawing inferences from academic papers :). The authors are careful to qualify their statements in the publication itself--the abstract is just a teaser and it takes time and practice to be able to interpret research results appropriately within certain contexts (for example, the participants had relatively low caloric intake).
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