Matt Metzgar

Online Status

I've added a new "widget" to the side of the blog.  This one, courtesy of Plugoo, allows me to chat with site visitors when I'm online.  All you do is type in a message and hit send, and if I'm around I'll reply.  If you're new to the site, or if you have a health-related question, or if you just want to say hi, feel free to use this tool.

I'm not online that often, but at least this opens up the possibility of making more connections.  Talk to you soon!

Stealth Exercise

I think one of the benefits of walking as a tool for fat loss is that you can do a lot of it "under the radar".  By this I mean that you can perform a large volume of walking without 1) stimulating hunger, and 2) overtraining and setting off the body's alarm system.

For example, if I walk an hour it really doesn't increase my hunger much, and it doesn't lead to a huge increase in my daily caloric intake.  In comparison, when I ran my one-and-only marathon years ago, the training made me ravenously hungry.  After I would run 12 or 15 miles, I would be hungry for days; it was as if I couldn't get enough food in. 

I actually gained weight during my marathon training.  Even though I was doing a large volume of aerobic work and burning lots of calories, I took in even more calories due to the hunger.  I think my body switched into survival mode, trying to gather as many calories as possible and hoarding them in the form of fat storage.

You can look at this process from a hunter-gatherer viewpoint.  If a hunter-gatherer is having to walk more than usual to find food, more calories are being expended for food procurement than are being taken in, and hence the body will burn some stored fat. 

In comparison, what would drive a hunter-gatherer to run 12, 15, or 26 miles looking for food?  Times must be pretty tough if you have to work that hard for some food.  Hence, the body may read this situation as an emergency, driving the person to eat more and ultimately store more body fat.

I see similarities to this in terms of modern training methods.  I've read many times where people start an exercise routine and blast their body with lots of weightlifting and lots of running, yet they do not lose any weight.  Walking is more of a ho-hum method for weight loss.  It's not as exciting as other forms of exercise, but it gets the job done.

Growth Hormone and Exercise

In response to the comments about sprinting, I looked further into the relationship between growth hormone(GH) release and exercise.  In terms of sprinting, I found that that the average peak serum GH concentration from a single 30 second sprint was between 10 and 20 ug/L.

In terms of resistance exercise, I found that the average peak serum GH achieved during acute resistance exercise was between 5 and 25 ug/L.  Similarly, the average peak serum GH achieved during acute aerobic exercise is also between 5 and 25 ug/L.

So it appears that either high-intensity sprinting or high-intensity resistance work can lead to similar increases in growth hormone.  Looking at other papers, I found that the growth hormone response to high-intensity exercise decreases somewhat with training.

Lose 1 lb A Day

"Lose 1 lb a day" sounds like a line from a bogus infomercial.  Yet this is exactly what one person apparently did in a wild experiment.

I've mentioned before that if a person exercises (walks) 1 hour a day they will lose roughly 1 lb a week.  So what would happen if a person did all seven hours of exercise in one day?

Ron Brown did just this and apparently did lose 1 lb of fat in 1 day.  The rest of his website is worth a look as well.  In addition to lots of exercise, he advises cutting calories - something I do not endorse.  But at least his ideas are based on a truthful principle: ultimately, you need to burn more calories than you take in to lose weight.

Sprinting versus Interval Training

I've been looking more into the routines of master sprinters, and what contributes to their leanness across the years.  I found some information here, where a few sprinters have posted their weekly routines.  What's amazing is that some of these sprinters do no types of endurance work, yet they remain lean.   

This led me to think a bit more about sprinting compared to interval training.  The two are often lumped together, but they really have two different objectives.  Interval training, with its short rest periods between work intervals, is designed to help a person run faster, but the primary application is for distance events.  For example, interval training has been shown to improve 5k times.

Pure sprinting work is much different.  Here the focus is on brief sprints, with long rest periods in between to fully recharge the muscles.

We know that interval training, such as the Tabata protocol, is effective for burning fat.  Yet we also know that sprinters, who may do no interval training or endurance work, are very lean.  So which is better for overall health and fat loss?

I think one clue comes from my post about runners gaining weight as they age.  They are putting in lots of miles, yet they slowly gain weight.  So what's missing?  Intensity and the corresponding hormone release.

This is covered more in the nice book, "Ready, Set, Go, Synergy Fitness" by Phil Campbell.  Growth hormone production naturally declines with age, and intense exercise is the only way to slow this decline (short of hormone drugs).

When a person performs interval training, they are not going to be exercising at the highest intensity.  They will have to lower the intensity a bit if they want to complete all the intervals.  I know this from experience when I do the Tabata interval training (20 second sprint, 10 second rest, and repeat 7 times).  If I truly go 100% on the first sprint, there's no way I will make it through all 8 sprints without really dragging.

Also, my other thought is that if a person never goes 100%, such as in a short sprint, wouldn't they eventually lose this ability over time?  After youth, nature's law is "use it or lose it", and if a person doesn't use their maximum capacity occassionally, it seems likely it would diminish.

Perhaps top sprinters like Maurice Green and Justin Gatlin don't have good endurance.  Perhaps they can't even run a mile for all I know.  But is this bad?  How much endurance is necessary for health?  Aerobic exercise has been shown to improve health outcomes, but the type, intensity, and amount necessary are open to debate.

From my readings of hunter-gatherers, their main endurance activity was walking.  Perhaps the proper combination of walking and pure sprinting can give the best of both worlds: high-intensity sprinting which releases hormones that burn fat and keep us young, and lots of walking which also burns fat and provides cardiovascular benefits.

Running, Aging, and Weight Gain

Here's some research on how running relates to aging and weight gain.  The research shows that even in those runners doing high mileages, (50+ miles per week), there is still an increase in weight and waistline over time.

Strangely, the author of this study recommends that people must do more running to stave off this weight gain.  The author states that running distance must increase annually by 1.4 miles per week to stop weight gain. 

Instead of just running more and more miles, there are better methods to halt age-related weight gain.  I've posted before about masters sprinters, and how they are remarkably lean throughout the life cycle.  To me, this seems like a much better route than logging hundreds of miles.   

What's Your Pyramid?

After years of experimentation, I've fine-tuned how much exercise is appropriate for me.  I don't think that any "formula" out there really works - everyone has different exercise capabilites and also different recovery abilities. 

For myself, I've found that a lot of walking, moderate amounts of vigorous aerobic activity, and a bit of weightlifting works very well.  I've condensed this into a "pyramid" below to simplify things.

If someone is naturally muscular, they may do better with more weightlifting.  If someone naturally excels in aerobic activity, they may do better with more running.  It all depends on a person's physical attributes and genetics.  So what's your pyramid?

Hunting Ability and Reproductive Success

Here's a good paper I came across, "Why Do Good Hunters Have Higher Reproductive Success?"  This paper reviews the research showing that the best male hunters in hunter-gatherers societies usually have better outcomes related to reproduction, such as more mates and more surviving children. 

This paper looks at various hypotheses as to why this happens.  Higher reproductive success may be due to the higher social standing of successful hunters, or it may be due to their superior physical abilities, and hence superior genetics.  The paper discusses these and other theories and attempts to test their validity.

Motivation: Beg, Borrow, and Steal

As I've mentioned before, hunger has historically been a major factor in motivating physical activity.  Given that in the modern world food is plentiful, secondary sources of motivation are needed to stay active.

I believe in getting motivation to exercise from wherever a person can.  This can include "tricking" oneself.  If you're scheduled to exercise 60 minutes, you can always tell yourself that you'll just do 15 minutes and see how you feel.  Then, after you're up and moving, you are more likely to continue and accumulate more exercise time.

I think too many people are waiting for a feeling of "pure" motivation to sweep over them and guide them to success.  In my opinion, human motivation is much more messy.  Some days you don't feel like doing anything, and that's when you need to find motivation wherever you can.  You can break exercise into chunks, talk yourself into it, exercise while doing something else, or promise yourself some kind of reward for exercising.   

Should Everyone Lift Weights?

When you look at research studies on weightlifting, you often see positive outcomes: subjects gain muscle mass, power, etc.  Yet this is all "on average."  If you dig a little deeper, you find that 1) some subjects dropped out of the study, 2) some subjects got no benefit from weightlifting, and 3) some subjects occassionally have negative responses to weightlifting.

I'm wondering if people should be more encouraged to "go with their genetic flow" when it comes to exercise.  If a person has no response (or a negative response) to weightlifting, isn't that saying something?  Perhaps that person should not be lifting weights at all.

It is easy to imagine that hunter-gathers did different physical things based on their genetic strengths.  As I've mentioned, genetic talent is often overlooked in explaining top performances.  Perhaps a tribe had a couple of really good runners, men who could run great distances to find new game.  Other tribe members may have been better at strength activities such as butchering game.

It is doubtful that each hunter-gatherer excelled in all these physical areas.  If all men could run, lift, or throw things with the same ability, this would make the women's task of finding a man with good genetics very difficult. 

You can see that many modern sports are set up to allow people with different genetic gifts a chance to shine.  Football has a variety of positions, and these positions all require different degrees of strength, speed, agility, and throwing ability.  Very few players are "interchangeable"; only a few genetic marvels can excel at multiple positions (at least at the NFL level).

So if you try to lift weights and continually burn out, perhaps lifting weights just doesn't suit your genetic profile.  Conversely, if running distances doesn't agree with you, then that activity may not be worth pursuing.  It may be better to go with the flow and engage in activities you naturally excel in to some degree.