T Nation

Vege vs Meat Diets

Would any of you guys like to comment on the following article. Any criticisms of it?

Amer J of Clin Nutrition, Vol. 76, No. 3, 511-517, Sept 2002

Effect of protein source on resistive-training-induced changes in body composition and muscle size in older men

Mark D Haub, Amanda M Wells, Mark A Tarnopolsky & Wayne W Campbell

Background: Aging is associated with reductions in muscle mass and strength, but nutrition and exercise interventions can delay this progression and enhance the quality of life.

Objective: We examined whether the predominant source of protein consumed by older men influenced measures of muscle size and strength, body composition, resting energy expenditure, and skeletal muscle creatine concentrations in response to 12 wk of resistive training.

Design: After consuming a lactoovovegetarian (LOV) diet for 2 wk, 21 men aged 65 ?? 5 y were randomly assigned to either consume a beef-containing (BC) diet (n = 10) or to continue the LOV diet (n = 11) throughout resistive training. The BC diet included 0.6 g protein per kg per day from beef and the LOV diet included 0.6 g protein per kg per day from textured vegetable protein (soy) sources. The remaining protein in the diets came from self-selected LOV sources.

Results: The mean total protein intake for both groups ranged from 1.03 to 1.17 g ??per kg per day during the intervention. Men in both groups had improvements (14???38%) in maximal dynamic strength of all the muscle groups trained, with no significant difference between groups. With resistive training, cross-sectional muscle area of the vastus lateralis increased in both groups (4.2 ?? 3.0% and 6.0 ?? 2.6% for the LOV and BC groups, respectively) with no significant difference between groups. Body composition, resting energy expenditure, and concentrations of muscle creatine, phosphocreatine, and total creatine did not differ significantly between groups or change over time.

Conclusions:

These data suggest that increases in muscle strength and size were not influenced by the predominant source of protein consumed by older men with adequate total protein intake.

They were on a lacto/ovo (dairy/egg) vegetarian diet, not a vegan diet. Eggs are a great source of protein for bodybuilders. This study is misleading. I would like to see a study with a vegan based diet versus a meat diet.

Skep-o-cism meter just went through the roof.

stole my thunder… I was gonna post this. Intriguing study, but I would take it with a grain of salt until corroborating studies come out (even though Mel Siff introduced it)

I was just reading thru the forum and this post caught my attention. 'Cause I’ve been working in the lab a whole lot lately and not spending my requisite 10 hours a week on medline, I missed this one.

Before anyone jumps to any conclusions here, it's important to have a bit of a historical perspective. The same authors did a few studies in the 90's where they showed exactly the opposite...a diet high in animal protein induced increases in lean mass and decreases in fat mass. On the other hand, the Lacto-Ovo diet actually increased fat mass with no change in lean mass.

So the only logical conclusion is that research sucks, right!

Of course not! With this study, it's interesting to note that body mass, lean mass, fat mass, and metabolic rate did not change over the course of 12 weeks of strength training. Herein lies the problem. 12 weeks of strength training in older individuals certainly increases strength (as seen in this study) and lean mass while decreasing fat mass. It's been shown time and time again. Therefore if you see a study that doesnt increase lean mass, regardless of the dietary treatment, it's a problem.

I think the conclusion (These data suggest that increases in muscle strength and size were not influenced by the predominant source of protein consumed by older men with adequate total protein intake) is misleading since the study should have produced changes in body comp and it didnt (short of the one measure of thigh volume).

John, could this gain in strength but not in LBM be attributed to the nervous system adapting before muscle hypertrophy can take place? Your thoughts please.

Just a general observation; the older folks (late 50’s +) who come into the gym where I work out don’t seem to change that much. They do talk of having more energy around week 6-7 though. My questions are: what were these guys doing before the study? It does seem strange that there was no intergroup variance much less intragroup variance. And isn’t 21 too small a sample group to be drawing conclusions about the population in general?

The study doesn’t seem to take into account the lower testosterone levels of older men. Since the men already would tend to have low T levels, any increase in estrogen due to the soy intake would be inconsequential, right? If the same study were conducted on younger men, any estrogenic effects of soy might have come into play. I’m just speculating here.

To Ike:

I really like your Skep -o- cism! It?'s great! :slight_smile:

To all:

All the research showed me is that:

  1. precious public funds should not be spent on useless and pointless research as this one;
  2. Those Researchers don’t have any clue what weight training and nutrition are all about;
  3. When things are so clear that no one else’s bothering with them, so weirdos will actually think:“Let’s do research for fun!”
  4. Bad research on older men is likely to do squat for 20ers like most of us;
  5. I’ve yet to see the usefulness of having a PhD when producing that kinda crap!

Most importantly, this research is good for a laugh and research shows that laughing is important for well being! So all in all, I’m grateful! (now, I’ll go to NAAFA board…I will feel extremely well tonight…Naah I’m kidding :0) )

-LPdSB

12 weeks of strength training certainly increases lean mass in older men. The bulk of the research literature has shown this. Therefore our first assumption should be that 12 weeks induces neural and mechanical changes. When this study didnt show it, it made me think that it wasnt done very well. BUT, the exact protocol used in this study was used in the other studies I mentioned, meaning that this very program produced hypertrophy in this exact population in the past. Im wondering why it didnt in this study.

Secondly, this is an intervention study looking at differences between 2 treatments and considering that the "power" of the study was good (or the ability to detect real differences between groups), the subject number was probably ok.

Third, I think the soy and estrogen link is inconsequential here and may very well be so in young men too. Remember, while some t-mag writers like to think of soy as estrogenic, this idea is not supported in the scientific community and if there is any link, it's with certain soy isolates, not whole soy protein (as used in this study). Also, the testosterone question is moot since both groups probably had the same t levels to start with. I think the soy addition in the Lacto Ovo group was not to bias the study against soy but simply because it's an adequate vegetarian control group. The study was designed to show that meat is better than veggie (as was shown in the other studies). But it didnt.

Finally,

In response to the following quotes :

“Those Researchers don’t have any clue what weight training and nutrition are all about” - Understand that one of the authors - Mark Tarnopolsky is an MD/PhD is probably the most intelligent man in this field and also happens to be an elite athlete himself. In addition, he is the man responsible (along with Dr Lemon) for the research showing that athletes need more protein as well as the studies showing P+C after workouts is critical, as well as a bunch of the research showing the importance of creatine…I could go on all day.

  1. When things are so clear that no one else’s bothering with them, so weirdos will actually think:“Let’s do research for fun!” - Not true at all. This sort of undermines the research in this field. I dont understand what’s so clear here. It’s not clear to me that one diet would be better than the other. I have a pro-meat bias but that doesnt mean that a soy, egg, and dairy diet might suck.

  2. Bad research on older men is likely to do squat for 20ers like most of us; - This is a decent study, I just dont understand it yet. Besides, researchers care more about preventing disease and dysfunction than making 20ers leaner an bigger (Damn them!)

  3. I’ve yet to see the usefulness of having a PhD when producing that kinda crap! - Again, the study isnt all that bad. Besides, since Tarno has an MD and a PhD, I guess neither is worth very much.

Ok, in all seriousness, Im sort of kidding with my review of your criticism but you should really know who you're criticising before the slander begins.

It just looks to me that weight lifting and eating enough protein are good for even older guys. It’s not surprising that any minor differences in the effects of differing protein sources didn’t show up in only 14 weeks, 12 of which were on different diets.
Longer term studies might show a difference but they are harder to do I suppose. It seems like starting with guys with a background of weight training and only changing their diets might make more sense since the intial training effect is going to show strength increases on even a marginal diet.

Glossed over the intragroup changes. My bad. Still, given the hypothesis of influence and their decision to reject it, I am still not convinced the sample size is large enough unless it is being used as a tickler study: get funds for a larger one. I can draw conclusions from this group about this group yes, but not apply to the larger pop. I can only estimate from this group to the larger pop with a certain level of confidence: this sample may be highly skewed…leading back to the question, what were these guys doing before: why this group of guys, etc.