Ben Greenfield Podcast 170

Podcast #170 from is-aerobic-training-bad-for-you-how-to-easily-measure-your-body-fat-with- laser-accuracy-and-much-more/ Introduction: In this podcast, is aerobic training bad for you? How to measure body fat accurately? How to use an elliptical trainer properly? Aloe Vera juice, high protein diet and headaches, electronic bike shifters and training for a hard hike. Ben: Welcome back folks! It’s Ben Greenfield and it’s been a little while since we’ve actually had an official podcast since last week, we had a bit of a hiatus while I was off travelling and actually racing down in Jamaica at the Jamaica triathlon, which I actually happens to win after getting a gold medal at the ITU World Championships the week before. So I’ve had a really successful couple of weeks in triathlon and I actually put out an article over at BenGreenfieldfitness last week because I received some emails and some Facebook messages that were actually accusing me of illegal performance-enhancing drug use, and so this week on , I actually did admit to using performance-enhancing supplements, and you can go read that article in which I come clean over at . Along with another article that came out this week, which is the first in a seven-part series that I’m writing about getting a better body and that particular article, it came out this week, was about three steps to get nicer shoulders. This week, I’ll be tackling a bunch of great questions that are coming from listeners as well as releasing a short interview about a new way that I’ve found to measure body fat. Now, in addition to that, we have a few special announcements that we’re gonna start with, so let’s jump right into those. Special Announcements: So, first of all, I received many applications for the new podcast host position that has opened up, for the new podcast host of this podcast and that will be the person who I will be bantering with each week. I’ll be announcing either next week or the week after who that new host will be but we’ve got some great folks who kinda put their name in the hat and that’s gonna be fun to have a new host on. Now, if you go on to the show notes of this podcast episode, podcast Episode number 170 at , you’ll see some of the special announcements and in particular, one that I


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Transcript of Ben Greenfield Podcast 170

Page 1: Ben Greenfield Podcast 170

Podcast #170 from



Introduction: In this podcast, is aerobic training bad for you? How to measure

body fat accurately? How to use an elliptical trainer properly? Aloe

Vera juice, high protein diet and headaches, electronic bike shifters

and training for a hard hike.

Ben: Welcome back folks! It’s Ben Greenfield and it’s been a little while

since we’ve actually had an official podcast since last week, we had a

bit of a hiatus while I was off travelling and actually racing down in

Jamaica at the Jamaica triathlon, which I actually happens to win

after getting a gold medal at the ITU World Championships the

week before. So I’ve had a really successful couple of weeks in

triathlon and I actually put out an article over at

BenGreenfieldfitness last week because I received some emails and

some Facebook messages that were actually accusing me of illegal

performance-enhancing drug use, and so this week on, I actually did admit to using

performance-enhancing supplements, and you can go read that

article in which I come clean over at

Along with another article that came out this week, which is the first

in a seven-part series that I’m writing about getting a better body

and that particular article, it came out this week, was about three

steps to get nicer shoulders. This week, I’ll be tackling a bunch of

great questions that are coming from listeners as well as releasing a

short interview about a new way that I’ve found to measure body fat.

Now, in addition to that, we have a few special announcements that

we’re gonna start with, so let’s jump right into those.

Special Announcements:

So, first of all, I received many applications for the new podcast

host position that has opened up, for the new podcast host of this

podcast and that will be the person who I will be bantering with

each week. I’ll be announcing either next week or the week after

who that new host will be but we’ve got some great folks who kinda

put their name in the hat and that’s gonna be fun to have a new host

on. Now, if you go on to the show notes of this podcast episode,

podcast Episode number 170 at, you’ll

see some of the special announcements and in particular, one that I

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would pay attention to, if you’re a triathlete, is the May 27 through

June 3rd, all inclusive Kona triathlon camp that I’ll be at down in

Hawaii and you can actually check that out by going to the link that

I have there in the show notes for that camp. Finally, this show is on

Stitcher, so you can listen to BenGreenfieldfitness podcasts on your

iPhone, your Android phone, your Blackberry, your WebOS phone,

whatever you happen to have, whatever fancy device you happen to

have, and you can get entered to win $100 when you grab that

Stitcher app or Just chose promo code:

fitness. And then finally for those of you who didn’t hear, my brand

new book “Top 20 Fueling Myths” came out last week. I’m super

proud of the information that I have masked in this title. It is

available over at, so go check that out. Surf

over to, and that’s actually a great website to

throw into your iTunes subscription list or onto your mp3 player as

well to supplement this podcast. Those are usually at anywhere

from 3-5 weekly podcast, typically a little bit shorter than this one

but some great information for you endurance junkies and that

book is on the front page over there if you go to, so go grab that seven bucks. Really worth

the read. You will definitely be smarter than most sports

nutritionist after you go through that book. But it is super simple to

understand and easy to read, so check it out at Okay, one quick special message and we’re

gonna move on to this week’s listener Q and A.

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Listener Q and A:

Raminta: Hi Ben, this is Raminta. I’m calling in from Baltimore, Maryland

and it’s a question for your podcast. This is in reference to an article

a friend of mine had sent, and the article is titled “The Many

Negatives of Aerobic Training” and this is written by Charles

Poliquin and this article goes on to list a lot of bad things like

aerobic training raises cortisol, accelerates aging, there’s more

inflammation and oxidative stress and on to a handful of other

things. But it was never really quantified as to what is the aerobic

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exercise that causes these harmful effects. So, for example, within

90 minutes, that one jog causes my cortisol to increase and the

potentially these bad effects can also can strength and enable

training counteract these bad effects as the article had suggested. So,

thanks so much. Bye.

Ben: So, this was an interesting article. I will link to it in the show notes.

But it was written by a gentleman named Charles Poliquin, and he

basically gave five different reasons why aerobic training is bad for

you. And his reasons were: 1. Aerobic training raises cortisol and

accelerates aging. 2. Aerobic training increases inflammation and

oxidative stress. 3. Aerobic training decreases reproductive size and

function and lowers androgens which are basically, sex hormones in

animal. 4. Aerobic training causes acute oxidative stress and

cortisol elevation. And number 5. Aerobic training compromises the

immune system. Now, Raminta’s main question was: How much

Aerobic training or what type of aerobic training would need to be

done to cause these types of effects. Well, let’s go ahead and go

through these reasons one by one. The first is that aerobic training

raises cortisol ad accelerates aging. So, the idea behind this is that if

you’re cortisol levels are chronically elevated, your body can store

fat instead of burning fat and high cortisol amounts can also lead to

gain in visceral fat in your belly. Now, the reason that accelerated

aging is listed as something that goes hand in hand with that is

because if you have a high amount of cortisol can increase the

amount of oxidants or free radicals in your body. So, free radicals

are basically something that increases cellular turnovers, cellular

damage, can cause things like wrinkles, greater risk for chronic

disease, and all of the things that people tend to die from and

essentially it ages you. And no matter what you’re going to do,

you’re going to create free radicals but you are going to create them

more intensively when you exercise and particularly when you

engage in aerobic exercise. The cortisol study that he cites is from

the Journal of Psychoneuroendocrinology, which shows evidence of

high cortisol level in experienced aerobic endurance athletes. Now,

these were long distance runners, triathletes and cyclists, and their

cortisol levels were compared to control group with no athletes.

Now, while the training level of these athletes is not actually cited,

it’s likely that they were engaging in a high amount of long term

aerobic training. And typically as most of you know, the amount of

training that an aerobic athlete does is in my opinion, more than

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they actually need to do. And so, it is certainly likely that most

aerobic trained athletes are running around with higher levels of

cortisol and thus a higher propensity to age faster than their non-

aerobic training counterparts, especially if they’re seriously into the

sport and doing kind of a traditional higher quantity, longer hours

style training program for things like marathons and triathlons.

Now the second reason that was listed was that chronic

inflammation is a major issue and a major result of chronic aerobic

exercise. And remember that chronic inflammation is different than

the acute inflammation that occurs when say, you sprain your ankle.

Chronic inflammation happens when you are constantly creating

these free radicals which are elevated via exercise, when you’re

constantly elevating your insulin levels, which is something which

that’s created from say, fueling with a lot of high carbohydrate type

of foods or you chronically increase your cortisol levels, which again

is something that can be accomplished through lack of sleep,

through stress and through a high amount of exercise. So you get

this chronic inflammation response and your body gets this

repetitive physiological stress that’s placed upon it. Aerobic exercise

certainly causes oxidative stress, we know that. Interestingly, Mr.

Poliquin does not mention the fact that anaerobic training, cross fit

training, weight lifting also significantly increases oxidative stress

as well. However, we’ll concede the fact that aerobic training

compared to those other styles of training causes more oxidative

stress. So, the particular study that was cited was an older study in

the Journal of Sports Medicine and Physical Fitness which found

that marathon runners had higher inflammatory markers than in

control groups. So they had a higher level of this oxidation going on

created from all these free radicals. So, a newer study, since that

time, in current microbiology actually tested the effect of probiotics

on oxidative stress and in this study, it was found the aerobic

exercise that they used in the group in that study did cause chronic

aerobic stress. Interestingly, probiotics were actually found to have

a beneficial effect against that stress. Now in this particular study,

the people tested were semi-professional cyclists. So again, we’re

talking about people who are engaging in a fairly high amount of

aerobic training, as a semi professional cyclist is probably riding a

bike anywhere from three to five hours a day. And when you’re up

around that level, you certainly are gonna have greater amount of

inflammation and a greater amount of oxidative stress.

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Now the third reason given was decreased reproductive size and

function and this was actually citing a study in the Canadian

Journal of Applied Physiology which tested the effects of aerobic

swimming on rats, and it found that the intense endurance exercise

that these rats were doing in the water was causing a dysfunction in

their male reproductive system. I decided to look into this study a

little bit more and it turns out that the rats were performing 3 hours

of swimming a day, five days a week for four weeks in a row. There

were swimming to complete exhaustion. So this is a fairly high

volume of exercise once again.

So far we’ve seen that for the first three reasons given, we’re talking

about semi professional cyclists training many, many miles a week

on the bicycle, we’re talking about rats who swim until they’re about

to drown three hours a day and we’re talking about a long distance

runners, triathletes and cyclists who are experienced in training

quite a bit. So far, we’re talking about levels of aerobic exercise that

probably would not actually surprise the people or the rats doing

this amount of aerobic exercise that it might not be the best thing in

the world for them. We are not talking about 30 minute lunch time

bouts in the treadmill, or even 60 minutes of aerobic exercise a day,

we’re talking about a lot more than that so far. So the next study is

or the next reason cited is acute oxidative stress and cortisol

elevation from aerobic exercise. In this case, it was a study in the

International Journal of General Medicine that found that an acute

aerobic exercise session significantly raises inflammatory

biomarkers, and cortisol and epinephrine. Now when you see the

word acute, that means an immediate response in this type of

biomarkers like cortisol, like epinephrine and acute inflammation.

Now it’s interesting that this is cited as a negative because this type

of response, an immediate increase in the cortisol and epinephrine

and an inflammation, is how your body becomes more fit after

exercise; whether it’s a weight training session, an anaerobic high

intensity training session or an aerobic training session. Any of

these types of training sessions are going to result in what basically

looks like World War II in your muscles, in your blood stream and

in your body. And as you recover, your body bounces back, it’s

what’s called a hermetic response and you grow stronger. If acute

inflammation was not happening as response to exercise, the

exercise would be no good. So, this particular reason that he cites is

complete bunk for two reasons, really- first, because it happens in

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both aerobic and anaerobic training and second because it is the

reason that you get more fit. So, you can basically throw that

reason to the side. The final reason that he cites is that long term

aerobic exercise compromises the immune system. And he says

that there’s ample evidence that aerobic training leads to immune

suppression and this certainly is true. What we’re talking about is

fairly long continuous, 90+ minute exercise sessions, each day. And

those exercise sessions are actually in a fairly moderate to high

intensity, about 60-80% of maximum oxygen uptake. So, we’re

talking about doing fairly hard sessions, for about 90 minutes a day.

Now, most folks are not doing that amount of exercise training and

the training typically, to attack the immune system in that way,

needs to be done in a state of relatively low calorie intake, along

with relatively poor recovery, poor hydration, poor cool down, poor

warm-up, poor post exercise supplement, food intake and so it

certainly is possible to suppress your immune system if you treat

yourself like crap and go out and exercise at a fairly high intensity,

like run on the treadmill for 90 minute sessions a day. Again we’re

talking about a very small percentage of the population that actually

does stuff like that. So, the nice thing is that there is a fairly decent

follow up article that the same author Charles Poliquin wrote after

he wrote this other article. And in his follow up article, he basically

listed some ways that you could combat the effects of this type of

aerobic exercise. Now the reasons that he listed or the ways that he

listed you could combat a lot of the stress caused by aerobic exercise

would be one to take antioxidants. And specifically, what he

recommended was taking Vitamin E, selenium and zinc. Now, the

problem with this recommendation is that these are three isolated

antioxidants and while they do have good potential for fighting the

free radicals that you produce during exercise, they’re also

associated with a higher risk of stroke when taken in isolated high

amounts, particularly Vitamin C and Vitamin E. I personally

recommend a full spectrum of the antioxidant intake rather than

taking isolated antioxidants if you’re trying to fight inflammation

from exercise. And that would mean that you’re including lots of

vegetables, fruit seeds, nuts in your diet and that you are also

preferably including, if you’re exercising a lot ,some type of full

spectrum antioxidant for example like Solar synergy from Alcapra

or Super berry from Living Fuel- Those are probably the top two

that I recommend and personally use. He recommends strength

training as a way to lower chronic inflammation and provide

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protection against oxidative stress. This was interesting. He cited

one study in the Journal of Strength and Conditioning Research

that compared the inflammatory response of two different strength

training protocols. Both of the protocols were cited as reducing

oxidative stress and lowering inflammation over pre-training levels.

The interesting thing is that they did not use a group, a control

group that was exercising aerobically. So in my opinion, this

research is completely useless when it comes to comparing strength

training to aerobic training in terms of the actual inflammatory

response. However, what’s going on here in this study is that folks

who take up an exercise program are actually teaching their bodies

how to fight inflammation better. And that’s going to happen if you

are engaging in a program that is not creating excessive oxidative

stress like the type of stress that would be created from say,

swimming to exhaustion three hours a day, doing these long hour

and a half continuous, 80% bouts on the treadmill, training as a

professional cyclist and engaging in some of the protocols that

naturally would increase oxidative stress. So what this comes down

to is that, and Raminta kinda asked this in her question, strength

training certainly has the ability to train your body to be able to

resist oxidative stress but there are no studies out there that take a

group, give them oxidative stress via high intensity aerobic exercise

than use strength training as a band aid to fix that process. So his

researches in his citations are fairly poor when it comes to actually

saying that strength might actually be able to do something like that.

He also says that basically you should practice judo or martial arts

as a way to increase antioxidant capacity and decrease oxidative

stress. Citing a study in the Journal of Strength and Conditioning

research that found that practicing judo can increase resting anti-

oxidant levels that counteract the oxidative stress produced during

strenous exercise. What the judo was actually able to help out with

was recovery from an all out 30-second bycycle sprint followed by

30-mintues of aerobic exercise. And they compared how people did

using a group that did judo versus a group that did not do judo.

And the group that did judo had a greater ability to fight off the

oxidative stress produced from that type of aerobic training session

versus sedintary subjects. I would hazard a guess that it’s pretty

likely that if judo works for something like that, yoga would also do

the trick. So, don’t think that you necessarily have to go out and get

yourself a Gi and a belt and go do some kicking and some punching.

You could probably get away with just including stress relief

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techniques like yoga in your routine. And I certainly recommend

that as a way to combat some of the stress that you’re producing

during aerobic exercise. He recommends taking Creatin to inhibit

oxidative stress. And cites a study in European Journal of Applied

Physiology that found that Creatin supplementation could help

decrease inflammatory bio markers after aerobic exercise. And he

also found that rats that performed aerobic exercise actually had

higher levels of anti-oxidants in their blood when they used Creatin.

This is one of those deals where you have to use yourself as a case

study because Creatin can cause cramping. It can increase weight

and water retention. And so you need to make sure that it works for

you because if you’re fighting oxidative stress with Creatin but also

making yourself slower from some of the other side effects of

Creatin. It’s really not going to do you much good. I would like to

see whether Creatin added in to a supplemetation protocol that

already has anti-oxidants gives any additional benefit. It’s because

if you have to choose between taking anti-oxidants or taking Creatin,

you’re probably going to get better overall benefit from using anti-

oxidants. And then he recommends taking omega three fatty acids

like a fish oil as a way to combat oxidative stress. And that certainly

something that I would recommend and agree with. So, ultimately

what this comes down to is that the article was decent in outlining

some of the negative effects of aerobic training. But the type of

aerobic training cited was fairly excessive. So, we’re talking about

folks who are doing aerobic training at a level at which most folks

know it might not be the best thing for their body anyways. I think

it was a tweet that I saw from a professional triathlete during the

ITU world championships. A tweet or a blog post, he mentioned

that the race probably took about five years off his life because he

was going so hard. Most people who are out there doing Ironman

triathlons beating up their body with multiple marathons a year,

going out and doing very hard things to their body. If you were to

ask them if they think that that’s going to make them live longer,

most of them are smart enough to say that they don’t know or it

probably is doing a bit more damage to their body. And they’re the

type of people who want to expereince much out of life as possible.

And maybe give up a few months or a few years in the process. I am

one of those people. I would never argue that the type of Ironman

or triathlon training that I do is completely good for my body.

There is some excessive damage I’m doing to my joint. I do create a

lot of free radicals. I fight it with supplementation. I fight it with a

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good diet. I try not to do too much aerobic training and instead do

intense training as much as I can. But still, I imagine that my

knees aren’t going to last quite as long as somebody who exercises

for 30-minutes a day versus my hour and a half a day plus a few

really hard races. So ultimately, hopefully that helps you see that

exercise study or that article in the correct light. And I wanted to

spend some time addressing that just because I receive so many

questions about it this week. Okay, next we have a question that

was written in by Jeff.

Jeff: Is a three mile run on an elliptical machine the fitness equivalent of

a three mile standard run? For example, say my training plan calls

for a five mile run, which would typically take me about 40 minutes,

would a 40 minute elliptical workout be comparable? Also, on an

elliptical trainer, should I try to replicate my running gate and foot

strike as much as possible?

Ben: Well, this is a good question. For any of you who read the most

recent Lava magazine. I outlined the exact training protocol that I

used for iron man Hawaii in that magazine. And you’ll notice if you

read that protocol that I talk about the type of training that I did on

the elliptical trainer or an outdoor elliptical trainer that I have

called elliptigo. And there’s acutally been some decent studies and

similarities between elliptical training and running. And there’s

one study over at the University of Missouri. It measured oxygen

utilization, lactic acid formation, heart rate, and how hard people

felt like they were working on elliptical trainer compared to a

treadmill. And they pretty much found that the elliptical trainer

was identical to the treadmill in just about every respect. But it

created a lot less joint impact. So, we’re talking about a very similar

physiological response but less impact. So, you bounce back from

the workout a lot more quickly. They found that compared to

running, you do get a little bit more quadraceps utilization slightly

less hamstring activation when comparing elliptical trainer to

running. And so, the take away message from that is that if you do

have weak quads then elliptical trainer can help you to strengthen

those. And a lot of people really do have a low quadraceps to

hamstring strength ratio. So, it can certainly be helpful for that. I

would not completely neglect running though because if you do so

when you do go out to do a race or competition or run, you’ll find

that your hamstrings get sore. And you don’t have quite as much

hamstring strength. So, even when I was using the elliptical trainer

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for nearly all of my run sessions, I still ran once a week in my build

up to ironman Hawaii. There’s another study that found and this

was actually done at the University of Idaho which is my almamater,

that when your stride length increases on elliptical trainer you

actually burn more calories without you actually feeling that you’re

working any harder. So, if you’re just trying to burn calories and get

as much as a metabolic benefit out of the workout as possible, you

actually want to try to get as great as stride length as possible as you

can out of each movement on the elliptical trainer. Now

unfortunately, unless you’re using one of these elliptigo’s that I use,

you can’t necessarily adjust stride length on a standard indoor

elliptical trainer. But you want to make sure that you’re not

shorting yourself at all on that track. So, what I would do is try and

gets your stride length as long as possible. And then once you’ve

got your stride length as long as possible on the elliptical trainer,

then focus on actually increasing your speed of movement or how

fast you’re moving your feet on the elliptical. A few other things I

would mention to you if you’re using an elliptical to train for

running. I do like the ellipticals that include the arm motion

because you do get a greater metabolic benefit and you get some

upper body cardiovascular work in. You do need to be careful with

that as you can keep your arms in front of your body rather than a

little bit more behind your body which is where they’re supposed to

be when you’re running. So, it can potentially teach you to have

your arms at the wrong spot. So be aware of that if you’re using an

elliptical trainer with the arm movement for training for running. If

you use the elliptical trainer without the arms, try as much as

possible to go hands free on that. So don’t use the railing. Just

keep your arms at your side and move them without holding onto

the railings. And you can actually hold a very light set of dumbells

like anywhere from two to five pound set of dumbells if you want to

get a little extra upper body work while you’re using one of those

hands free elliptical trainers. So ultimately Jeff, you can do the

same amount of time on elliptical training as it would take you to

run. Focus on stride length. You don’t necessarily want to try to

mimic your running gate as much as possible and focus on stride

length instead. You can certainly use an elliptical trainer quite a bit.

I personally do. So, that was a good question.

Scott says: Based on your advice Ben, I’ve eliminated artificial sweeteners

completely from my diet. And I’m trying to eat more protein in

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particular. Recently, I have developed some bad headaches.

Sometimes, they seem to spike right after eating. During initial

heavy exertion when lifting weights can also cause a spike in

headache pain. Could this be due to my high level of protein


Ben: I think I’ve mentioned this before in a podcast but high protein diets

and headaches are fairly common and there are a few reasons for

that. The first is, when you switch to a high protein diet, you’re by

definition lower your carb intake. Carbohydrates carry about four

times our weight in water in the muscle. Your storage carbohydrate

or your glycogen carries a bunch of water. You shed a lot of water

and that dehydrates your body. So, we’re talking about loss of

blood volume, dehydration, and a dehydration based headache as

one of the reasons that you get that headache. Another reason is

because as you dump carbohydrate, shift to a high protein diet and

change your fuel sources especially if you’re skewing that a little bit

more towards a fat intake. You’re burning more ketones or free

fatty acids for energy. When you’re burning ketones that can cause

especially a lot of nausea, some irritability, and some headache

that’s typically due to you being stressed out just as much as you are

being exhausted. And that can be another reason that you get that

type of headache. The first reason, the loss of water, is simply fixed

by making sure that you increase your water intake. The second

reason, you simply got to work through. It typically takes anywhere

from seven days up to a couple of weeks to get used to burning

ketones as an energy source. I would caution you though with this

whole high protein diet thing and recommend that you go read the

recent article that I wrote at about why

most people are actually probably getting too much protein in their

diets. And I give you some good formulas there for figuring out

exactly how much protein you should take in, how you should be

doing it, and more reasons, from a biological level, why a high

protein diet is not all that hot for you. And I’m really not a big fan

of it. And yes, this is coming from a person who would get up to 70

to 80 percent protein intake back when I was a body builder. It

really is not all that great for your body. And you can go over there

and read why at, scroll down a few

articles underneath this podcast. It was a couple of weeks ago that I

wrote this. And this is podcast episode number 170. Or you can

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just go to and do a search for protein.

Okay, we have a question from Jennifer.

Jennifer says:I recenly read in a book that a study found that drinking aloe vera

juice could help relieve asthma symptoms. Have you ever heard of

aloe vera juice relieving asthma?

Ben: This is interesting. There’s only been one really small study that

wasn’t very well designed that showed some beneficial effects from

aloe treatment in chronically asthmatic patients who weren’t using

their inhalers, who weren’t using their cortico steriod treatment.

And basically, what they did was they gave them oral aloe extract in

a saline solution two times daily for about 24 weeks in a row. And

they found that 11 of the 27 patients who actually made it through

the study improved their asthma symptoms following that aloe

treatment. But they didn’t even do a statistical evaluation of the

study. It was really small. And it’s certainly not a study that you

would want to rely on to give you reason for curing your asthma

with aloe vera. However, aloe vera does have some really good anti-

inflammatory and anti-allergenic effects. And so if your asthma is

related to inflammation, to an immune system response, or to like

an allergy, then aloe vera certainly has some propensity to help you.

It’s basically got a bunch of different what are called antiseptic

agents in it. Antiseptic means that they have a potential to kill mold

or bacteria or fungus or viruses. A lot of cleansing capsules and

juices has aloe vera extract in them for that reason. Specifically,

you’ve got salecilic acid extract. There’s some nitrogen in there,

some phenols, some sulfur. So aloe vera is good for those reasons.

You’re going to find some really good anti-inflammatory fatty acids

in aloe vera. Cholesterol is one. Kampersterol is another. There’s

another sterol in there as well. A plant based sterol. And that’s why

it can help with allergic reactions. Why it may have some potential

for really helping out with an asthma reaction or an asthma attack,

that type of thing. And it also has a bunch of different immune

stimulators basically what are called polypeptides. And so, for an

immune system disease or something like asthma an immune

system response that is based or an asthma attack that is based on

immune system response. Aloe vera and the polypeptides could

help with that as well. I personally have only used aloe vera juice a

few times in my life. And I was particularly taking it to help me

recover from a pretty big dose of antibiotics that I was going

through about a year ago. And all I did was drink aloe vera juice

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three times a day. I’ll put a link to the stuff that I used in the show

notes. It doesn’t taste all that hot. It has the ability to give you a

little bit of a gag reflex. But it’s worth a try. I can’t say that research

shows that it could help. But let me put it this way; it’s probably not

going to hurt you. There’s not a lot of risk of using it in moderation.

So, give it a go. If it turns out to be successful to you for sure, write

into the show or call into the show and let me know.

Robert: Hi Ben, this is Robert Anker. I have a question for your upcoming

podcast where maybe you can talk about your experience using the

shimano Di2 electronic components during a recent Las Vegas ITU

championship and how they compare to components that most of

us are using and whether you recommend consideration for

upgrading to this type of electronic device. Thanks a lot.

Ben: Okay. So, I’ve been using these new electronic gear shifters.

They’re called the Shimano Di2. It’s an electronic gear shifting

system on the bike. It’s relatively new. It’s been around for a

couple of years. It enables you to shift by touching an electronic

switch that’s on your handle bars instead of using levers that you

normally use to shift. And the way that it works is that these

switches, they’re connected to a battery pack. And the battery pack

is connected with internally run wires on your bike to a little motor

that drives your front and your rear derailer. So it shifts the chain

from your big chain ring to your small chain ring or vice versa on

the front. And then it switches between your cogs and your cassette

on the back. And it’s incredibly smooth. I have been falling in love

with this system because when I’m climbing a hill, there’s no clunk

when I shift. There’s no slight hesitation when I shift. I can shift

from my handle bars. I can shift from the end of my arrow bars.

There are switches on the end of both. And I swear that I save

energy and a significant amount of time from using these things.

I’m extremely impressed. And it’s going to be hard for me to ever

go back to using a non-electronic gear shifting system after I’ve

used this one. You got to charge it. Typically, a charge would last

anywhere from 1000 or 2000 hours. So, you’re not going to run out

of battery life during a ride in most cases. They’re a little bit

expensive. But ultimately, I think that if you’re doing something

like really long bike rides or something like triathlons where you’re

trying to save as many seconds as possible, then this is a good buy.

I save two seconds here. I saved three seconds there over the

course of 112 miles when I use these things next year in Ironman.

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That could potentially add up to a good three or four minutes of

saving just from using electronic shifters. So, I do recommend it.

And I’m really stoked about my experience with them so far. So, it’s

a good question.

Brian: Ben, I’ve got a question for you. This is Bryan Stern from Southern

California. Here’s the question. My buddies and I are doing the

Grand Canyon rim to rim in about six months. It’s a 45 mile run

hike from one end of the Canyon to the other end and back. And

we’re going to race it. It means that we’re going to do it as fast as

we can. Then we’re now debating the best training plan. So my

belief is that we should be spending about two-thirds of our time

doing cross fit plyometric style workout to strengthen our legs,

quads, glutes, core and to develop more flexibility in our hips and

IT bands and then spend the remaining one-third doing long runs.

My training buddies on the other hand have a different opinion.

They think we should be spending about two-thirds of our time

doing long training runs and then one-third doing cross fit or

plyometric type training. So in short, I think strength and flexibility

and agility is most important to train for this. And they think long

distance runs are the most important things to train. Just so you

have some background, we’re all marathoners. We’ve all been

doing cross fit and plyometric style training for the past five years.

So, we all have a pretty solid base to work with. The debate is really

just about for the next five to six months leading up to the race.

How do we spend our time? Is it two-thirds strength training,

plyometrics, stretching, flexibility and one-third long runs or is it

the reverse? I appreciate your thoughts. I’ll talk to you soon.

Ben: So, the answer to this is your both right Brian. Farther out from the

race, you’re going to want to do a little bit more of the long distance

running, long distance hiking, long distance training. And as the

race approaches, you’re going to want to shift to a higher amount of

cross fit or plyometric type of training. This is basically called

periodization. It’s used in most endurance sports. From swimming

to cycling to running and it’s actually used in most power and

strength sports as well. But the idea is that as the event approaches,

you’re going to shift the training of your energy systems more to the

high intensity speed based energy systems and away from the long

slow aerobic energy systems which you are hopefully developing as

you are farther away from the race. So, what this allows you to do is

be a little bit fresh7 because you’re putting in less volume as your

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event approaches. And it also allows you to develop a high amount

of neuromuscular training, speed training, power and strength that

you are going to be able to rely on for putting down a good time as

the event approaches. So, what I would be doing is taking until the

point where you are anywhere from eight to twelve weeks out from

your event. And during that period of time up to the point where

you eight to twelve weeks out from your event, focus more on doing

this like injury prevention training and longer slower sessions. And

then once you are about eight to twelve weeks out, start to shift your

training to be more favored towards doing this type of cross fit

plyometric style of training that you’re talking about. And that’s

really the way to do things. No matter what type of training you’re

doing, swimming, cycling, running, and triathlon adventure racing,

whatever, it typically works out a lot better to do volume over

intensity. Now, that being said, there is a twist to this. And that is

that most people start their volume training too early. So, let’s say

that you are signed up. Let’s say that you’re going to do an Ironman

triathlon or a marathon. And you’re going to do it at some point in

the summer. A lot of folks are hopping on the bike, the treadmill,

doing tons of really long slow aerobic training, extremely long

draining joint pounding sessions for a race in the summer way back

in November or October in some cases and even in December.

When in reality, in most cases, you don’t have to start any of your

big time aerobic type of training until you’re anywhere from 20 to

24 weeks out from your event. So, in most cases, you’re looking in

not needing to do stuff like that until January or February. So, what

I like to do during those months that come before January or

February especially for a summer type of race which is when a lot of

people’s big races are is, I just play. I do a lot of basketball, tennis,

explosive training speed stuff. And that way, essentially what you

get is a speed volume speed sandwich. And that works really well

when it comes to getting yourself periodized for the actual race that

you’re going after. And the first part of that speed sandwich, the

top of the speed sandwich that you do in the off season is really not

doing many of the type of activities or motions that you’re going to

be doing in your race. So, a lot of the times for me, it’s skate skiing

or tennis or basketball and these types of things. And then I start

into my volume training. And then my next round of speed training

is more swimming and cycling and running and doing the type of

activities that I’m actually going to be doing during my event. So,

it’s cross training speed, sports specific volume and then sports

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specific speed. So, hopefully that gives you a macro idea of what

this should look like when you’re doing a lead up to a race like this.

So, hopefully that helps and that was a good question. Finally I

have, before we go into this interview on body fat testing, a nice call

that I received about

Dr. Patrick: Hi Ben, my name is Doctor Patric Kelevin. My wife was kind

enough to buy me your terminator program. And I completed my

first Ironman. I just wanted to say thank you. So, I have small kids,

a three year old and a sixteen month old. I didn’t think I was going

to have the time to actually train for an ironman. And I have to tell

you it was fantastic. Your thoughts and your program were very

efficient. I was unfortunately not able to keep up with everything

that was in your program. I was training 68 hours a week. It gave

me the idea to complete it. And I end up finishing the Ironman in

12 hours and 41 minutes. I macked up in the middle of the pack but

there’s always room for improvement. I’ve got Saint George week

coming up in May. I’m going to be using your program a second

time. And I’m going to go for it and I’m going to be using it a little

bit more. But really, it was fantastic for a guy that on a time crunch.

Your program was extremely efficient and opened my ideas about

working out and training. So, thank you. And my phone number is

6302927766. My e-mail is [email protected]. And I just wanted to

tell you what a great program and thank you for your help. And

have a good day.

Ben: Alright folks, you can check that out,

Congratulations to you Patrick. And let’s go ahead and jump into

today’s feature topic on biometrics body fat testing. And I’ll be sure

to put a link to biometrics in the show notes. Here we go.

Feature Topic:

Hey folks, it’s Ben Greenfield. And with me on the call today is

Louis Desilva. And the reason that I wanted to call up Louis and

interview him is because he has a background as a physicist in

medical imaging. And it was probably a year and a half ago when I

was reading Tim Ferriss 4 Hour Body book. And he was talking

about his advanced method of measuring body fat that was just

incredible accurate and super easy to use. So, I’m like oh I’m going

to look into this. And so, I looked into getting one for myself. But it

turned out that it was expensive and designed for big fitness clubs

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and looked like something that I probably wouldn’t be able to just

keep in my office and measure my body fat after a workout.

Ultimately though, in the past few weeks, I followed up with the

people who produced this piece of technology that we’re going to

talk about today. And it turns out that there’s now this consumer

version available. So, I was able to get my hands on one and try

one out. And I got an incredibly accurate body fat measurement

using this. I’ve don’t underwater weighing. I’ve done bioelectrical

impedence, skin fold, bod pod. I’ve done decsa scans. I’ve used just

about every method there is of testing body fat. And this one was

pretty cool. So, I know that a lot of you out there are into tracking

your body fat. Maybe you’re working with a coach or a trainer and

you want to be able to share your body fat measurements with them

or even convince them to use something like this. And Louis is

going to tell us what it is, how it works and the background behind

it. So, Louis thank you for coming into the call.

Louis: Well Ben, it’s a pleasure to be here.

Ben: So, tell me about what this thing is called and then how it came to

be and how it works.

Louis: Alright. Ben, the basic nature of the body metrics which is an

ultrasound device and the origins are the background in medical

imaging. And we started looking at a variety of systems. One of

which is ultrasound. And I met up with a friend who at that time

was working for 24 hours fitness. And he indicated that it’d be

really nice to have an alternative approach for measuring body

composition than a Caliper which in many ways is still pretty crude

approach to measuring fat fitness. And at that time, we talked

about ultrasound being a modality. But the challenge is Ben, that

historically ultrasound is very expensive. Most ultrasound systems

that people are familiar with costs ten hundreds of thousands of

dollars. So, what we did was basically took the same technology

specifically ultrasound and put it into a small device that we hope is

affordable to fitness clubs and now individuals.

Ben: I got you. So, in terms of ultrasound, people have seen ultrasound

as far as like imaging a baby in the womb or maybe have used one

in a physical therapy setting to send some sound waves down to an

area that needs a little bit of therapy on an injured joint. But in

terms of actual measurement of body fat, how does this work?

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Louis: That’s a good question. You’re absolutely right in the sense that the

technology is the same as used for imaging babies, looking at

muscle tears, etc. Our case is that our device is what is called a-mod

ultrasound which instead of doing a direct imaging approach, it

sends a beam of ultrasound from the device itself. And that beam

penetrates the skin and goes into the tissue and then you get echoes

at the major interfaces, the main tissue boundaries. And so, in our

particular case when you’re looking for body composition, you’re

interested in subtaneous layer of fat, how thick the fat layer is. So,

we process the ultrasound and determine exactly what that

interface is. And then you measure directly the fat thickness. It’s

not a fold. It’s not some hypothetical thickness. It’s the true fat

thickness as measured with the ultrasound.

Ben: So, how trained do you have to be to use one of these things. I

mean, a lot of people listening in, they’re not physical therapist or

personal trainers the people at home. How much training is

involved with this?

Louis: Yeah. I’d like to think that we made this system easy for people to

quickly learn how to use it. One of the things is because we

calculated body composition. We do multiple points in analogous

way to Caliper. So, anybody that’s used Calipers immediately

knows where to place our device and where to make accurate

measurements. And so, we’ll do anywhere from one side to as many

as the ninth side formula to get more accuracy. So, that part of it if

you know those positions, it’s very simple. We have a training video

that comes with our personal devices. And with the professional

devices we actually give online training. But what we find is that

typically for most people, if they spend half an hour playing with the

device, following the procedures and with a little bit of our guidance,

they quickly get up to speed and are able to make accurate

measurements. It’s a very simple device to use. Its software and

interface we try to make very simple. So, we find that most people

get up to speed very quickly and are able to make accurate

measurement pretty quickly.

Ben: I’m glad you mentioned that it’s basically like this piece of software

that you have on your computer, on your mac or on your pc. And

it’s cool because for me I just need to do my chest, my stomach and

my thighs. And I immediately got my body fat percentage spat out

at me. And you’ve got multiple measurements that you can use for

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guys and girls on this software. But the ultrasound device was just

plugged into the computer as I scanned. But what I thought was

cool was you actually could, as you scan the area, it would image the

muscle and show the muscle area. So, you could actually track

responses in the muscle. Are there more advanced uses of this if

people wanted to get a little bit more scientific?

Louis: I mean, you kind of hit it on the head. One of the unique capabilites

of ultrasound of course is that you can scan and get some quality of

images. Our device is different than traditional medical ultrasound

devices to do the two dimesional imaging which had higher

resolution. Our device, because you manually scan, gives you the

opportunity to scan larger. For example, you can do a full thigh

scan where you literally slide the device from upper thigh down

towards the knee. And you’ll see the fat layer very well defined.

And you’ll see the muscle. And you’ll see the different muscle

groups. And the advantage of that as you point out is that it gives

you the opportunity to look both the fat and muscle directly. And

so, if you’re entering an aggressive diet program, exercise program,

the beauty of these images is that they really give you both. It gives

you the opportunity to get your fat layers changing and your muscle

layers changing. And down the road, we also hope to go beyond

that because ultrasound is used to determine whether your steak is

marbled. So, whether there’s intermuscular fat ultimately, our

device can give you a handle on that. So, that’s something that

we’re still in the research phase and hoping to get some stuff down

the road.

Ben: Got you! So, if I’m listening in and I am a personal trainer and I

want to toss this in my office and use it with some clients in my

personal trainer office. Or if I want to get really accurate body fat

measurements and I’m a consumer and I want to share them with

my coach or share them with my trainer, what kind of price point

am I looking at because I want to make sure that people know the

approximate price they’ll plan on for something like this.

Louis: Again, currently we offer two systems of the biometrics. The first

old version which is intended for individuals, families, or trainers

that are just starting, and that’s 495 dollars. And that’s our starter.

For trainers with lots of clients, who want to customize reports or e-

mail their reports directly to their costumer, we have the

professional system. We have two options for the professional

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system. One is a licensing option which is $949 for the system.

That’s the first payment. And then an annual payment of $149

which gives you extended warranty on the device. So, if anything is

wrong with the device, you send it back and repair it. And it also

gives you annual software updates. So, as new science is being

integrated into the software, you’ll get that. So, that’s part of the

licensing package. And then we do have a one time payment option

where you can buy the device single one time payment. And that’s

$1895. So, we’ve tried to make it so that almost everybody

hopefully can now get one of our systems. And the value that it

brings specifically to trainers and such is as you point out. It’s a

unique tool. It gives you ultrasound scans. It gives you something

that people are very familiar with. Everybody has had an

ultrasound scan or atleast seen an ultrasound picture. So, the

underlying technology is very familiar to most people. And there’s

definitely a buy in to the technology itself which a lot of our trainers

who bought this systems have found right from the beginning that

their clients buy into the accuracy of the system and to the

technology. And they don’t have to explain how ultrasound works.

Ben: Cool. So, folks compared to a bodpod which this big space age is

looking devices that you sit in. Some gyms have them, some

physical therapy place has them or compared to a dex-a bone scan,

this is just as accurate. And I think it’s pretty cool that you can just

put it next to your computer at home. So, check it out. I will put a

link in the show notes to this. It’s basically like a wand and a piece

of software. And you can see it right there in the show notes to this

podcast over at We’ll put a link to that

biometrics device. And Louis, thank you for coming on the call

today and explaining how this works.

Louis: It’s a pleasure. And if anybody has any questions, I’d be happy to


Ben: Alright folks, I’m going to put a link to that system in the show

notes. I’ve got one here on my desk. It’s pretty cool especially the

part where you can actually visualize your underlying muscle

structure. You can share it with your trainer. For those people that

I coach, you can share it with me. And it’s just a very cool way for

those of you who want to pop whatever you said it was 300 or 400

bucks on a really cool way to measure body fat. It’s extremely

accurate. And it’s something that the whole family can use.

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Actually, the main reason that I put this out too is also because I

know a lot of you personal trainers out there listening could benefit

a lot from this thing. It’s a very cool way to set yourself apart and be

able to measure body fat way more accurately than you can with a

scale or electrical impedence. And a little bit more comfortably

than you can with hydrostatic underwater weighing. Alright folks,

that is going to wrap it up for this week. Be sure to tune in next

week where we may already have our new host in action. It’s either

going to be next week or the week after. Go to the show notes for

this podcast, podcast number 170 over at And while you’re there, if you

want to keep this podcast going, you can donate a dollar or you can

also leave the show a review in iTunes. Alright, that is going to do it

for this week. Have a healthy week. This is Ben Greenfield signing


For personal nutrition, fitness or triathlon consulting, supplements, books or DVD’s from Ben Greenfield, please visit Pacific Elite Fitness at