Interval Training

Improve your running economy and race times.
Interval Training at your VO2 Maximum Pace.

Runners with a high VO2 maximum absorb more oxygen; they can race faster.

Economic runners burn less oxygen at a given pace: they�re frugal with oxygen use. They too can race faster.

The best 5K and 10K and marathon performances are run by athletes with high VO2 max and good running economy.

Regular training at 2 mile & 5K race pace improves both VO2 max and running economy.

The aims of Interval Training then, are:
· Improve Maximum Oxygen Uptake Capacity or VO2 Max--the amount of oxygen which you absorb.
· Get more efficient at utilizing the oxygen you absorbed.
· Improve leg turnover and running economy.

Just what does VO2 MAX mean?
VO2 max, or Maximum Oxygen Uptake Capacity, to use its formal name, is the amount of oxygen we can absorb into our cells in one minute while working at full capacity. It�s a measure of fitness expressed in milliliters per kilogram per minute.

You can predict your VO2 max with 95 percent accuracy by running around a track on a windless day for 15 minutes. The distance run to the nearest 25 meters is noted, and Bruno Balke�s formula is used to predict VO2 max. After a base of 6.5, this follows a linear pattern of 5 mls/min/kg. for every extra 400 meters covered. For example, if you run 10 laps (4,000 meters), it predicts 56.5 mls/min/kg. 4,400 meters gives a 61.5 VO2 max. If 4,450 meters is run, VO2 max would be:

VO2 Max = 6.5 + 0.0125 x (distance run in 15 minutes)
= 6.5 + 0.0125 x 4,450
VO2 Max = 62.125
World class runners have a figure of 80 (male) and 70 (female).

Top British coach Frank Horwill, says, �The best way to improve VO2 max is to run between 80 and 100 percent of VO2 max. One hundred percent equals the athlete�s 3K pace; 95 % equals 5K speed; 90 % is 10K speed. �Work physiologists believe training at 95 % VO2 max brings the best results--though one Russian physiologist of note--Karibosk, thinks 100 % (3K or two mile pace) is better because it tunes up the anaerobic pathway. Note--3,000 meters is run at 60 % aerobic and 40 % anaerobic.

�Physiologists are agreed the percentages at the higher level (100 -- 95 %) should be done for 3-5 minutes� duration, repeated many times in one session, with a short recovery. The lower percentages (90 -- 80 %) should be for 10-20 minutes, also with short recoveries.�

At 2 mile pace, the heart, lungs and entire circulatory system work at maximum capacity to maintain speed. This stimulates your VO2 maximum to increase.

Months of long runs have increased your VO2 max substantially. Now it�s time to make additional VO2 max gains by training at close to your maximum oxygen uptake pace. Applying this modest stress to your lungs, muscles and circulatory systems will stimulate your VO2 max to rise: you�ll be able to race faster.

The Track
You can run these sessions on a track--tracks create a more reliable yardstick to assess progress. Interval training is a precise and progressive form of training. You change one of Waldemar Gerschlers� 5 variables such as increasing pace by one second per quarter mile, once a month to:
· further stimulate your VO2 system;
· force you to run more economically;
· use all your muscle fibers--making you stronger; and,
· develop pace judgment.

These goals are best achieved on a flat surface of known distance. The advantages to track sessions are:
· Same distances all over the country...within a couple of yards or meters.
· A smooth surface.
· You get away from traffic, dogs and pedestrians.

There are some track rules. Look before you change lanes; avoid lane one if possible; and if you think someone ahead of you is going to veer left to the inside after his interval, chances are, he will actually veer right. Assume everyone else�s brain is malfunctioning, and you should stay safe. Don�t expect to educate all of your fellow joggers and walkers.

Rest During Interval Training
The rest period is the Interval! Generally, you should take less than 90 seconds rest during interval sessions. The greatest stimulation of heart development occurs in the first 10 seconds of the rest period. If you�re running reps at the appropriate pace for you, it should only take 30 seconds for the heartrate to get below 130. The extra minute is for your mind, not your body.

Strong enough for Interval Training?
You need a good base before commencing serious speedwork. Never lose sight of the strength phase. Keep your long runs and the modest pace threshold sessions throughout the year.

Your mileage and strength base increased the number and size of your mitochondria, the organelles inside the muscle cells that make ATP (adenosine triphosphate), which fuels your muscles. Your patient strength build-up facilitates your shift to speedwork.

Interval Training Basics
· Do a warm-up and stretch. Flexibility determines your range of movement, your potential stride length. Muscles are 10 percent longer when warmed up. Muscles work better when they are long--exerting the same amount of force but with less effort.
· Don�t jump straight into long sessions of intervals.
· Feel as comfortable in the last 400 meters as you did in the first 400.
· Run the last few reps as fast as the early ones.
· Don�t feel wasted afterwards.

Whether training on your own, or in a group, here�s how you can progress if doing formal VO2 max training for the first time. See page 90 for the table of suggested training speeds at 95 and 100 percent of VO2 max.

Week One--Bends & straights--stride along the straight and jog the bends at a steady pace. Run eight to twelve laps--giving sixteen to twenty-four striders--you should not feel exhausted. Short striders of 20-30 seconds require little concentration.

Week Two--16 x 200 meters with 200 interval recovery. The surface may tempt you to run faster; hold back to decrease injury potential.

Week Three--10 x 300 meters. A little slower speed than the 200s; take a 300 recovery. Run two straights and one bend for the repetition; two bends and a straight for the recovery. Use lane 4 or 5. This reduces the strain on your ankles, knees and hips--there is a tendency to lean into the curves.

Week Four--8 x 200 and 4 x 400 meters. You will need to run a little slower than your 300 pace in order to keep going for the extra 100 meters. Pace should be no faster than 2 mile race speed...100 percent of VO2 maximum, or about 10 seconds per mile faster than your best recent 5,000 meters. Sessions at this modest pace give your leg muscles a chance at adjusting to the track surface. Use the sprinters start point when running in the middle lanes. The relay boxes are also a useful guide. Otherwise, running in lane five adds 26.8 meters per lap if the lanes are 42 inches wide. That�s about 5.4 seconds for the 80 seconds per 400 meter runner.

Week Five--10 x 300 again. Pace judgment will improve with practice; aim to run them fairly even. If you run more than 40 miles per week, build toward at least fifteen reps.

Week Six--4 x 200 and 6 x 400 meters with the same jog recovery. Even with a full lap recovery, this session is quite hard. Aim to maintain good form for the entire lap...assess yourself in each hundred. Ask...is my form going? Quarters have the advantage that you start and finish each effort at almost the same place.

Week Seven--4 x 300, and 3-4 x 600.

Week Eight--6 x 200, and 3 x 800 meters. Then alternate sessions using mostly short reps at 2 mile pace, with sessions of longer reps at 5K race pace.

This speedwork helps you get the greatest possible amount of the energy from your highly trained running muscles. Think about the elements of good form. It helps you to maintain efficient form for longer periods. As the months and years progress, you�ll become less bouncy, and more efficient at running...if you practice.

You don�t have to run these sessions on a track. You can use a watch with a beeper to run a session of one or two minute efforts with a minute rest...on grass, or paths and road. Tracks can help you keep interval training precise in any city; you can measure your progress, and the eventual decline as you age.

Practice good form, and intervals at close to VO2 max will:
· Improve your flexibility and running efficiency...enabling you to race faster.
· Recruit even more of your fast twitch fibers, more of your total fibers to shift your limbs at this pace.
Which:
· Improves your leg strength and therefore your stride length--allowing you to run faster.
· Raises your leg turnover or cadence.
· Improves overall speed and economy.
· Your smoother running requires less ATP--your energy lasts longer. You can run farther at a set pace.
· Your pace judgment improves.
· You improve your neuromuscular coordination even if you forget to work on form.
· You breathe deeper--intercostals and diaphragm muscles develop tone.
· Your anaerobic buffering system is enhanced; your lactate tolerance goes up. Which means that your muscle fibers will contract despite the presence of high levels of lactic acid.
· The body�s ability to process oxygen improves.
· Your aerobic capacity and VO2 maximum rises.
· You�re able to run longer before you reach oxygen debt...and you�ll be better able to handle that debt...at a given speed.
· You�ll race faster.
· You can even talk during the rest interval. The running becomes social.

Adapted from Chapter 10 of Running Dialogue, plus a few lines from Chapter 4 of 10K & 5K Running, Training & Racing.

Syndicate

Email to a Friend
Friend's Email Address:


Your email address:


Message (optional):

Sign Up for our Newsletter
Get these articles and gear information sent to your inbox.
 

Posted: April 8, 2003