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Shooting Blindly in All Directions
section 1
Aerobics– our silver bullet–knocks-off excess fat, snuffs heart disease and hypertension, offs stress and dispatches depression. Hope keeps us coming back day after day firing that slug at whatver wolf is huffing and puffing outside our door. The thing with firearms that's true of aerobics is that unless you hit your target dead on, you're left with one less round and one pissed-off wolf.
The following improves your cardio aim!
How often we train, how hard and for how long–Frequency, Intensity and Time–effects aerobic accuracy. The daily gym scene, street runners, cyclists and swimmers are often great examples of frequency and duration conscious exercisers. Regulars invest at least 3 days each week and spend easily 30 to 60 minutes panting and sweating. They at least get their weapons loaded and squeeze out a few rounds. Some hit, but most miss.
Doing-in the Big Bad Wolf, the Werewolf or a Wolf in Sheep's Clothing demands some discriminating trigger work. You've gotta know which one you're shooting at, and which to pick off first.
Let's say the Big Bad Wolf is that midsection pudge threatening your self image. The Werewolf is last year's crawl of a 10K footrace threatening to devastate your ego. And the Wolf in Sheep's Clothing is hypertension threatening only your life. Once in your sights you can take 'em all down with only three shots. Now, take careful aim with training intensity.
Understand that any good training program includes a base phase where workouts are relatively easy. A build phase then elevates training load and brings about improved speed or hill climbing ability. And, finally the peaking phase conditions both physiological and psychological stamina to handle prolonged hard exertion. Each phase is defined by your training load, or intensity. Follow the righteous path of periodization and your aim will be true.
Fire first with the base phase, and take out the Wolf in Sheep's Clothing. That shot of low intensity training by itself may also scare off the other two wolves. Health is your first priority and building your aerobic base gradually with LSD–Long Slow Distance–over several months is always a bullseye. Your target training range is 65% to 75% of your age-predicted heartrate maximum.
If the other two wolves are still at your door, then take aim at the Werewolf. Even with the silver bullets this one's a bad mutha–hey, we're talking 'bout your ego–so it may take two shots.
Draw a bead on your goal race, maybe nine weeks away. It's a 10K and you want to beat your personal record. Double tap with a five week build phase then a four week peak phase, which includes one week of taper. Build greater speed with a faster pace. After months of base training you're ready to pick it up and run. Your build runs will be between 80% to 85% of your HR Max. Over your last four weeks drop your run duration and raise your intensity to 90% to 100% of HR Max, with supra race-pace surges of 30 seconds to maybe 5 minutes to peak your aerobic power. This part's as mentally tough as it is physically. The week before the race, rest and stay tuned with only a couple of short, faster-than-race-pace runs. Bury that lupine menace on race day.
Now, if the Big Bad Wolf is still hanging around your red-brick house, you have a security problem. Someone is slipping the beast some table scraps. Who might that be? Better check with the wolf in the mirror.
section 2
Choose between these pistols for your target practice. To make things easier on yourself when training use a heartrate monitor to keep you in the groove.
- Phil Maffetone's 180 formula is the simplest of the bunch: don't train with a heartrate above 180 minus your age. He has world class aerobic athletes' testamonials to back him up. His maxim: aerobic efficiency best improves health and performance.
- Similarly the Talk Test keeps us at a reasonably low intensity as long as we can carry on a conversation without labored breathing. Very convenient "black / white" litmus test for training intensity.
- In their triathlon conditioning programs the Olympic Training Center in Colorado employs RPE–Rating of Perceived Exertion–based on breathing, subjective self-evaluation and easily applied numerical scales. This intuitive form of biofeedback can be as precise and valid as any other once training / exertion awareness is fine tuned.
There are two RPE tables of note. The classic Borg scale uses numerals from 6 to 20 to signify training intensity from hardly noticeable to maximal exertion. And, the second is based on a 1 to 5x scale, and corresponds to the Borg scale yet is less cumbersome. I'm reasonably sure the 1 to 5x Training Intensity Zone featured on the Triathlete Magazine website was created at the Olympic Training Center in CO Springs. In any event, it's used there as well as by the well known Multi-Sport School of Champions, and appears, too to be referenced in the Inside Triathlon Training Diary from Velo Press.
- The widely used percentage of age-predicted heartrate maximum is simple, but requires a little math, a chart, or a calculator. Quickly, 220 minus our age times 65% to 85% provides our ideal training range, in beats per minute. The age-predicted maximum heartrate is subject to individual variation of up to 20 beats per minute. Typically, the target training zones are a little too low versus actual VO2 max.
- And, the Karvonen formula seeks to better personalize training levels by subtracting our resting pulse from the equation before computing training percentages, and adding it back in, afterwards. That training zone is based on heartrate reserve, which proves to be more closely related to actual VO2 max.
- Or, finally it's possible you've had your VO2 max measured directly in some way–perhaps via the Bruce or Naughton-Balke Protocols–or inferred by your own run results. If so, then you'll be able to most accurately prescribe your cardio program for maximum impact.
Confusing? Maybe at first. They're all describing pretty much the same thing–training heartrates within a target range specifically focus on a particular aspect of aerobic fitness. And, just as firearm choice is based on personal preference, so is cardio training. Whether our silver bullet is fired from a pocket-sized, 9mm., Glock semi-auotmatic, or Dirty Harry's .357 Magnum hand-cannon, it's precise aim, alone that drops the wolf.
section 3
What's VO2 max Anyway?
Our functional capacity is the greatest volume of oxygen we can consume each minute during exercise. The capacity to absorb, transport and use oxygen while exercising is developed by progressive aerobic challenges. That's at least 20 minutes of regular, steady, continuous activity using our larger muscle groups. Usually, we'll train at some percentage of VO2 max to bring about particular aerobic improvement. The guidelines above provide several ways of estimating training level based on a correlation between VO2 max, heartrate and breathing. To get an idea of how VO2 max or a training percentage based on exertion might be calculated have a look at the problem shown below, unless you're math-phobic.
Check Out This VO2 max Problem
This is taken from the Fitness Institute International's Fitness Testing Specialist Course.
Please note: if you're using Netscape you'll likely see a "square" in place of a small "dot" within the equations below. The "·" doesn't display properly when it's placed within formulas, or so it seems, but it does display correctly elsewhere--like at the beginning of this sentence or at the top of this page where it separates this website's sections. It is used below to mean, for instance, m times min.-1.
A 31 year old individual with a resting HR of 68 BPM reaches a steady 150BPM at a teadmill speed of 6mph and a grade of 2.5% and again at 160 BPM at a speed of 7 mph with the same grade of 2.5%. What's his approximate VO2max ?
First, let's organize all of the components to this problem. We'll need a manual like the ACSM Guidelines for Exercise Testing and Prescription, 4th Edition or a math degree to make sense of all this. The Guidelines', Appendix D includes Metabolic Calculations that are essentially plug and play.
Ready? Me either–I was an English major–but here we go anyway.
Here's the formula to figure this one–
VO2 max=SM2 + b (HR max - HR2)
where b= (SM2 - SM1) / (HR2 - HR1)
where SM2=SM+HC+VC
Of course, the above makes no sense yet. We've gotta know this (below) before going farther:
SM – submaximal workload (expressed in METs) : easy, that's 3.5ml/kg-1/min-1 aka 1 MET or O2 consumption at rest.
SM1 – 1st submaximal workload (expressed in METs): this takes a little figuring. It's 39.28.
SM2 – 2nd submaximal workload (expressed in METs): this also takes a little figuring (see below) and is 45.28.
HRmax – 220 minus age: simple, 189.
HRsm – submaximal heart rate at workload: this is resting heartrate, and is given. It's 68 BPM.
HR1 – steady state heart reate achieved at SM1: also given. 150 BPM.
HR2 – steady state heart rate achieved at SM2: given. 160 BPM
VC – Vertical Component: O2 consumption as per grade, 3.62 and 4.2 for SM1 and SM2, respectively.
HC – Horizintal Component: O2 consumption as per speed, 32.16 and 37.58 for SM1 and SM2, respectively.
1 MPH – in meters per minute, 26.8.
So, to find SM2, we do this:
a) convert speed to m·min-1…
in other words, miles per hour to meters per minute–
speed, in m·min-1 = (mi·h-1) x (26.8 m·min-1/ mi·h-1) , so…
(7 mi·h-1) x (26.8 m·mim-1/ mi·h-1) = 7 x 26.8 = 187.6 m·min-1
b) find the horizontal component (HC)…
in other words the energy expenditure in oxygen consumption in millilitres per minute–
HC = (m·min-1) x (.2 ml·ml·kg-1·min-1) / (m·min-1), so…
(187.6 m·min-1) x (.2 ml·ml·kg-1·min-1 / m·min-1) = 37.58 ml·kg-1·min-1
c) find the vertical component (VC)…
in other words how the grade or treadmill elevation figures into the energy expenditure in oxygen consumption–
VC = (grade) x (m·min-1) x (1.8 ml·kg-1·min-1 / m·min-1) x .5, so…
(.025) x (187.6) x (1.8 ml·kg-1·min-1 / m·min-1) x .5 = 4.2 ml·kg-1·min-1
d) now find the VO2 in ml·kg-1·min-1…
in other words the oxygen consumption, in millilitres per kilogram of body weight per minute–
* remember "rest" is 1 MET or 3.5 ml·kg-1·min-1
VO2 = (HC) + (VC) + Rest, so…
37.58 + 4.2 + 3.5 = 45.28 ml·kg-1·min-1
e) finally, find the energy expenditure in oxygen consumption in METs by converting from VO2–
E=VO2 x (1 MET / 3.5 ml·kg-1·min-1), so…
45.28 ml·kg-1·min-1 x ( 1 MET / 3.5 ml·kg-1·min-1) = 12.9 METs
SM2=45.28
Now, to find SM1, we do this again with the other components, or:
We simply turn to Table D-3, " Approximate Energy Requirements in METs for Horizontal and Uphill Jogging", page 299 of the ACSM Guidelines (4th Edition) and find essentially the same info within seconds without using any math! Either way,
SM1 is about 39.28
What's next? Solve for "b".
If, b= (SM2 - SM1) / (HR2 - HR1), then:
(45.28 - 39.28) / (160 - 150) = .6
And, that brings us back to:
VO2 max=SM2 + b (HR max - HR2), or
45.28 + .6 (189 - 160) = 62.68 ml ·kg-1·min-1
And, by dividing VO2 by VO2 max, it's easy to extrapolate from there that SM1 = 63% of VO2 max or 11.2 METs and SM2 = 72% of VO2 max or 12.9 METs. How does that correlate to the age-predicted range? Simple,
220-31=189
150 / 189 = 79% HR Max
160 / 189 = 85% HR Max
or, via the Karvonen Formula…
220-31=189
189-68= 121
150-68 = 82
160-68 = 92
82 / 121 = 68% HRR
92 / 121 = 76% HRR
…which is a little closer.
Still awake?
to article three to article five
Just So You Know
These are the original versions of the articles I've written for the popular Hungry Minds educational website. Read the unabridged versions here and read the edited pieces there.
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