Matt Metzgar

Heart Rate

I bought a Polar heart rate monitor the other week.  I was curious as to what my maximum heart rate is, and what it is during exercise.  I'm not one of those people who think a heart rate monitor is a required tool for exercise, but I thought it might be a good long-term purchase.  A person's maximum heart rate is supposed to decrease with age, so I will be curious to see if that happens for me over time.

Today during my pyramid interval training, my heart rate actually got up to 180 bpm during the second 400 meter run.  It was also interesting to see that the 50 and 100 meter runs did not raise my heart rate near as much as the 400 meter runs.

Over the next few weeks, I'm going to record my heart rate in different activities so at least I'll have a baseline to measure from.

Pyramid Interval Training

I've been trying something new lately in regards to running.  I call it "pyramid interval training".  Right now, the workout looks like this:

• 1 x 800 meters
• 2 x 400 meters
• 2 x 100 meters
• 1 x 50 meters

I try to run each interval at a solid pace, getting progressively faster as the distances get shorter.  My rest period between intervals is around 2 minutes, though I will work to slowly decrease this.

This type of interval training isn't exactly original - it has been around for decades under different names.  Former world record holder Sebastian Coe called his version of this "multi-paced training".  The idea was to work a variety of running paces within one interval session.  This was in comparison to more traditional types of interval training where roughly the same pace is used throughout the session (for example, 6 x 400 meters at about the same speed).

I'm hoping that the variety within my pyramid interval training will provide more benefits as compared to just working at one pace.  The main question for me was whether I should start with the longer distances and work my way down, or do the reverse.  I decided to go in the direction of increasing speed/shorteneing the distance because this would be close to that of a Stone Age hunt.  If a hunter-gatherer was stalking prey, it's likely that they would keep increasing the pace and finish with a final sprint as they closed in.

Are You Working Hard Enough?

I came across this thesis that looked at interval training and calories burned following exercise.  The study compared aerobic training, interval training, and high-intensity interval training.  This researcher found that high-intensity interval training created roughly double the post-exercise calorie burn of aerobic training or interval training. 

This paper also provides a good summary of other research regarding exercise and its post-exercise afterburn effects.

Exercise Intensity and Duration

I found this nice older study that showed how exercise intensity and duration affect calories burned.  First, the study looked at how many calories were burned following exercise (EPOC - excess post-exercise oxygen consumption).  The researchers compared different combinations of intensity and duration.

EPOC (liters)
%VO2 max	20 min	50 min	80 min
30%	1.01	1.43	1.04
50%	3.14	5.19	6.1
70%	5.68	10.04	14.59

As you can see, intensity made the biggest difference.  20 minutes at the highest intensity burned more post-exercise calories than any length at the lowest exercise, and more than 20 or 50 minutes at the moderate intensity.  At 80 minutes, post-exercise calorie burn was 15 times higher in the highest intensity group versus the lowest intensity group.

The researchers then looked at the calories burned during exercise to see how large the afterburn effect really was.  Here's a table that looks at total calories burned (both during and after exercise).

Total Exercise Cost (liters)
%VO2 max	20 min	50 min	80 min
30%	20.48	53.20	84.23
50%	38.95	100.46	160.59
70%	58.30	147.48	237.17

Again, intensity was the key factor as going from the lowest intensity to the highest intensity tripled the total calorie burn.

More Interval Training

Hot off the presses, this study compared the effects of four different types of aerobic training on Vo2max(aerobic power).  The four types were long slow distance, lactate threshold, 15-second on/15-second off intervals, and 4 x 4 minute intervals.  All training was matched for equal total work.

The two types of interval training resulted in significantly more improvement in VO2max than the other two types.  The 15/15 training increased aerobic power by 5.5% and the 4 x 4 training increased it by 7.2%.

Exercise Tools

I came across a couple of handy tools this week.  The first is this website that shows how many calories are burned for various types of activities.  It also gives the number of calories found in different foods.

The second tool is at this website.  It uses Google maps to determine exactly how far a distance is from point to point on a walking route.  I was able to map my usual walk through my neighborhood and determine exactly how far it is.

Diabetes

Here's a nice article in Men's Health that discusses diabetes.  Instead of the usual insulin injections that a doctor prescribes for diabetes, the doctor in this story had a much simpler idea: a low-carbohydrate diet.

Since carbohydrates are what raises blood sugar and hence causes insulin to be released, this doctor logically thought that limiting carbohydrates would limit blood sugar problems.  And for a good number of patients, this approach seems to work. 

As for the American Diabetes Association, they want long-term studies before they would endorse such an approach.  Until then, millions of Americans will keep suffering from this condition. 

Aerobic vs Anaerobic Exercise

Finally, I've found a good paper that compares aerobic versus anaerobic exercise.  Researchers split obese adolescents into two groups: 1) traditional aerobic training at 60 - 70% of VO2max and 2) short 30 second sprints with long walk recoveries.  Participants exercised 3 times per week for 40 to 60 minutes.

The result?  The two groups showed equal weight loss.  Both groups lost around 4 kg of fat and gained 1 kg of muscle over 12 weeks.

This study shows that it's the total number of calories expended that make the difference in weight loss.  The aerobic group took the steady route to burn calories each session, while the walk/sprint group used bursts and recoveries.  Though these two protocols may have different effects on other measures, such as hormones, if they burn the same number of calories they will lead to the same amount of weight loss.

Senior Sprinters

I came across this article discussing the Summer National Senior Games from a couple years ago.  The article highlights sprinter Dorothy Haskins who competed in the 100-meter dash at age 66. 

Know any 66-year old women who look like this?  I'm becoming more and more convinced that sprinting and middle distance running are huge keys to staying youthful.

Happy Easter!

I've been a little busy lately, but I hope to get some more posts up this week.  Until then, Happy Easter!