Today’s miracle pill is: Growth Hormone!

Posted on | April 22, 2009 | 10 Comments

It’s really no secret that training trends are driven more by fads than be science, effectiveness or evidence. I used to think that this was people looking for an easy solution. I still think there is an element of that for many but I think intellectual laziness is really more at the root of it. I see this time and time again on the internet training circles. Someone gets an idea that seems to make sense and repeats it. Before you know it, it’s “common knowledge”.

This annoys the hell out of me. I fully admit that I still have a lot to learn about training and physiology, by any real standard I’m a beginner in this field. That said, I really wish people would learn to check their sources, and verify things before sprouting off conjecture as fact.

I saw this trend a few years ago, when one of the geeks got the idea that you’d burn more more bodyfat if you did cardio in the morning, or in a fasted state when insulin and blood sugar levels were low. It makes sense, it sounds great in theory.

Somewhere, people made the leap from “that idea makes logical sense” to “it’s true!” without testing it. I knew something was up when I went to the gym at 7am and the meat heads were doing an hour of slow, plodding cardio (in the fat burning zone of course) before breakfast.

There was just one problem with this idea. While it made great sense, it didn’t work. I’m going to quote Lyle McDonald here (this has been passed around the internet extensively, I hope he doesn’t take offense to my reusing it, while giving him credit).

Now, we’ve known for years that, in general, the body will burn whatever fuel is most available. Studies reliably show that when you ramp up fatty acid availability to the muscle, the muscle burns more fat.

So the logic goes: do cardio in the morning, when there are lots of fatty acids available and you will burn more fat and thus lose more fat.
And the logic is 100% sound right up until the last part of it “…thus lose more fat.” A fundamental mistake that’s been held by researchers, physiologists, trainers and coaches for decades is that ‘burning fat during activity = fat loss’. You find the same argument in the ‘do low intensity activity because you burn a greater percentage of fat’ folks; they logic that burning more fat during activity = more fat loss.

The problem (well, there are many problems) is that they are focusing only on what’s happening during the exercise bout. That is, they are worried only about what’s being burned during the 30 minutes of activity. That’s problem #1: what about the other 23.5 hours of the day? Most (but not all) studies have shown that, when you look at total fat use over 24 hours in response to activity, the body will figure it out. For example, if you burn more fat during exercise, you tend to burn less fat the rest of the day; if you burn more glycogen during exercise, you burn more fat the rest of the day. Over 24 hours, it balances. At least two studies have shown (and note that this wasn’t in bodybuilders or lean folks) that as long as the calorie burn during activity is the same, fat loss is the same. They had folks exercise at either a low or high intensity for something like 70 or 35 minutes (calorie burn was identical in either case). Fat loss was the same over the course of the study.

The above is posted as a historical reminder that “what makes sense” and “what works empirically” are quite often two very different things. I’m seeing much the same thing here, with the current magic pill of the moment, Growth Hormone, or hGH.

There is still quite a bit we don’t understand about the endrocine response to exercise. I’m seeing the same kind of hackneyed claims about optimizing hGH secretion being bandied about as facts now. Just to be clear, I’m NOT saying that none of these ideas have merit, and I’m not saying that further investigation is not warranted. What I am saying is that it is irresponsible to promote ideas like “doing high intensity intervals while intentionally in a glycogen depleted state to optimize growth hormone response.” . Yes, that’s a tremendous idea, lets exercise at an intensity that by necessity is fueled by muscle glycogen (carbs) while carb depleted. I wonder if that will impact performance at all.

Below are a few of the recommendations I’ve seen regarding hGH optimization, and my equally unscientific opinion of them. However, I am making the point of stating that this is only my opinion, and is not the new one true gospel 8-weeks-to-a-body-that-will-make-supermodels-rip-your-clothes-off-or-your-money-back approach:

Avoiding all carbs after workouts – Personally I think this is idiotic. It is true that insulin inhibits grown hormone release. It’s also true that the very kind of high intensity workouts that stimulate hGH release will deplete muscle glycogen. Its pretty well established that this leads to an increase in insulin sensitivity in the muscles, which provides the chance for a “super compensation” effect. That is, it allows you to shuttle more glycogen back into the muscles than was originally there. At least one study has also shown an increase in serum testosterone (in men) with the consumption of protein and carbs post workout. By taking a reductionist approach and looking solely at the hGH response people are missing the big picture and really cutting into their recovery.

Trying to get workouts in the “hGH sweet spot” with regard to intensity. – This one is a mixed bag. I disagree with the logic here but the effect is probably fine. At least one study has shown greater hGH release when subjects exercised above their lactate threshold. It should be noted that this DOESN’T necessarily mean interval training. Yes, HIIT will be working above your lactate threshold. So will steady state cardio done with a bit of intensity. I really think you should be doing this anyway unless you’re an endurance athlete preparing for a distance event and omitting the high intensity work for a very specific reason.

Doing high intensity workouts while intentionally avoiding carbs. – Here we get into the “wtf” area. I’m not anti-low carb by any means (I eat pretty close to paleo myself). But let me break this down. Above a given percentage of Vo2 Max (the percentage depends on individual genetics and training adaptations) the fuel WILL switch from fats to carbs. Even if you eat a 0 carb diet, sprints will be fueled by muscle glycogen. Intentionally starving your muscles of the fuel they need won’t make you drop fat, but it will make your performance at that kind of training suck. Rob Wolf who is a big proponent of the low carb-paleo approach has written a good bit about the difficulties of doing high intensity power endurance work without adequate carbs. If you want to go super low carb feel free, but do it for the right reasons. This isn’t one of them.

Avoiding carbs before bed, and getting enough sleep – This is one of the few GOOD suggestions. hGH is normally released in a series of pulses throughout the day. The largest one takes place about an hour or so after falling asleep. The theory here is you want insulin levels as low as possible then to facilitate the largest release possible. This is one of the areas where I agree. It’s also something you should probably be doing anyway. Getting enough sleep, and high quality sleep is one of the most significant things you can do for your health, training and recovery.

Now as far as not eating before bed – don’t friggan obsess over it. This is one of those “makes sense” ideas that may turn out to be disproved later on. I’m not aware of any scientific studies showing a difference in recovery or progress between subjects who eat a late night meal versus those who didn’t (although if someone wants to give me grant money, I’ll be happy to conduct one). This is minutia stuff, and not the big picture. The 400 calories you ate after 9pm didn’t make you fat. The 3000 calories you ate over the rest of the day did.

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Comments

10 Responses to “Today’s miracle pill is: Growth Hormone!”

Shauna Weiss
April 23rd, 2009 @ 11:38 am

Love your comment on ‘no carbs and high intensity’. What a complete oxymoron! In order for muscles to fire at a highly intense level, there has to be glycogen stored. I’d like to ask Micheal Phelps if he could have brought home all those medals on no carbs.
Yash
April 24th, 2009 @ 8:08 pm

Great article. Up until now, I’ve been a fan of low carb dieting without actually adhering to said diet very strictly. A few weeks ago, I decided to tighten it up, and it hasn’t been the best experience. I won’t blame it on the low carbs, since I also switched to a lower calorie diet, while simultaneously starting a sport, and keeping a slightly scaled back version of my strength training. Basically, I changed a lot of factors at the same time, and the lower carbs doesn’t seem to be helping it. I think under the right conditions, it can work, just not for me at this point in time.

Also [I got into this in response to a comment of yours on Rusty's site recently], I think the scientific benefits of morning fasted cardio and HGH boost etc might be exaggerated and invented to make logical sense of the effects, but the effects seem to be there, especially for those who are a bit less out of shape. Once you get closer to a more optimal body comp and try to push even further, your body is smart enough to be stubborn and give you a pretty hard time getting really ripped and like you said, a lot of these things do become minor minutiae.

-Yash

PS – “this is only my opinion, and is not the new one true gospel 8-weeks-to-a-body-that-will-make-supermodels-rip-your-clothes-off-or-your-money-back approach”
… Well in that case screw your opinion, give me that second one!
Yash
April 24th, 2009 @ 8:10 pm

a bit *more* out of shape**
cmason
April 28th, 2009 @ 2:22 pm

Yash –

I’m not anti low carb by any means. I’ll even venture that for the right set of circumstances low carb diets can be ideal. But a lot of people seem to think that they’re a fix all.

Lyle McDonald said something I really, really liked on the subject of low carb diets. To paraphrase –

I upset everyone when I talk about these, because I don’t think they’re evil, but I also don’t think they’re magic.

As far as the fasted cardio:

In general I don’t think morning fasted cardio will do any HARM, but I question how much (if any) benefit it has over just doing the cardio any other time. I do take issue with the recommendation of high intensity training while going very low carb though.

If the training volume is low enough that muscle glycogen is not depleted this could be fine, but it’ll put a pretty serious limitation on your athletic development if you have to stop there.

As for the term “HGH flush” that people seem to be pushing around the internet lately, I have yet to see a single piece of scientific evidence showing a connection between the flushed hot feeling of a HIIT workout and the subsequent release in growth hormone.

I am always open to being proven wrong though, and will be happy to print it/link to it here if someone can provide the evidence.

I’d love to do a study where two groups of identical training status (untrained, recreational athletes, etc) performed an identical training regime. One group could do the GH optimizing hoopla, workout fasted, not refuel post workout, etc…

the other would not worry about fasting and get a good carb/protein meal after a workout.
Yash
April 29th, 2009 @ 11:11 pm

Its interesting that you mentioned that bit about a study, because as a student at a large research university, as well as a student of a major that requires research credits, I was wondering today if there were any decent sport physiology labs on campus. [I don't think there are] Ideally, a study like the one you said would answer a lot of questions, but the key phrase is “identical training status”. Two groups can have so many variables, which is why so much of the research in this field is shaky. Its almost frustrating, because you can really argue any side of any argument when it comes to health and back it up with “evidence”.
cmason
April 30th, 2009 @ 10:04 am

I agree. It’s really tough to find people with the same training status, which is why a lot of studies will use non-training college students. Practically EVERYTHING works on an untrained subject though, and it’s shaky to draw too many inferences from that to other training populations.

I think my ideal would be to take a college sports team in the off season (say during their hypertrophy or strength phase). After randomizing the groups train half one way and half the other.

Of course, to do this you need to convince a team coach to let you experiment on his athletes.
Skyler Tanner
April 30th, 2009 @ 3:16 pm

Here’s the thing about hgh (I wrote a damn article about it from a variety of sources over a year ago):
1. Insulin and GH can be high at the same time…after a workout.
2. GH is driven higher, according to the literature, by having carbs + protein after a workout.
3. Injected GH means fuck all, both on trained athletes and old folks. If injects mean dick, why would a 15′ spike after you workout mean anything?
cmason
April 30th, 2009 @ 3:53 pm

Thanks Skyler.

I thought remembered reading about #2 before, but a (very quick) search didn’t find the study.

I do remember reading about a number of other beneficial hormones (test and the like) being elevated by having protein and carbs post workout, but I wasn’t sure about growth hormone.

As you pointed out, the effects of GH are fairly small – certainly not enough to justify NOT replenishing muscle glycogen in my opinion.

But telling people that it’s not a magic pill apparently isn’t trendy.
Skyler Tanner
June 3rd, 2009 @ 11:58 am

C,

Here are the studies that show pro + carbs increasing GH post workout:
-Journal of Applied Physiology; 85 (4), 1544-1555, 1998.
-Journal of Applied Physiology; 76 (2), 839-845, 1994.

Hope that helps.

-S
Calorie Counting Guru
January 31st, 2010 @ 6:33 am

As far as eating just before bedtime is concerned, I think it is logic that eating late will push up your insulin levels which is not ideal for weight maintenance.

It’s just logic. I don’t think we need a study to reach a conclusion here. The thing is every little you do helps. Avoiding late meals may not contribute hugely but it certainly doesn’t harm your progress.