By Coach Steve
My pace per mile with regular speedwork is 30-seconds faster than
without! I just took 6 months completely off from run intensity
work, but I still kept running consistently at moderate pace (moderate
pace is most recent 5k PR pace plus 1-1:15 per mile). Before I restarted
run intensity work I tested my pace at 90% of max and I was surprised
to find I was going 30-seconds per mile slower than before. That's
more speed loss than I expected, but with my good base and a few
weeks of speedwork I can get it back.
Speedwork can take precious seconds off your race times, but it
can also cause injuries if done too soon, too fast, or too often.
To avoid these pitfalls, you need a plan. Here's some information
that should help out.
Speedwork is a structured workout that uses periods of pacing equal
to, or faster than, your race pace, sandwiched between recovery
periods. This fast training simulates the physiological demands
of race efforts, and serves as the ultimate tune-up for your race
season. When done properly, speedwork can improve anyone's pace
over any distance. The idea is to stress your body just enough to
invoke some adaptation to that stress, but not so much as to compromise
recovery time between workouts. Another name for speedwork that
you may be familiar with is interval training. Regardless of what
name you prefer, the workout entails repetitions of various predetermined
distances with recovery periods based on heart rate or time. Typical
distances for the repeats or intervals are from 200 meters to 1
mile for each repeat. The rest periods are determined either by
pulse (you wait for a pulse rate below about 70% of your maximum)
or by a predetermined amount of time. A warm-up and cool-down period
is always part of the workout and the total distance running "at
speed" rarely exceeds 3 miles.
A certain amount of base preparation is required for this type of
difficult training to be productive and non-destructive to your
body's tissues. This preparation can only come with a minimum amount
of easy mileage leading up to the intensity of the speedwork phase.
If you run consistently year round, at least four times per week,
then your body has probably been toughened-up enough over the long
term to deal with the rigors of speedwork. Occasionally we see runners
who only train twice per week, and their speedwork outing is one
of these two workouts. This is not recommended. When first timers
participate, their entire workout is only one-third to one-half
the duration, as compared to the "regulars" of our group. Despite
taking this precaution, there is usually significant soreness in
the days following the first-time speedwork session. The second
time at the track, "newcomers" can do most of the workout with little
or no residual soreness the following day. This soreness phenomenon
is similar to the day-to-day effects of an irregular workout schedule.
Anytime you miss four or more consecutive days of running, starting-up
again will cause soreness as your body goes through the hardening-off
process again. I recommend that runners who want to participate
in our track workouts run at least every other day for a minimum
of 15 miles per week of total mileage.
Physiological Adaptations to Speed
Maximum efficiency of any movement is achieved when each muscle
group contracts at exactly the appropriate moment for application
of force in the desired direction. When opposing muscle groups contract
simultaneously there still may be movement, but energy is wasted
is the process. Training a muscle to contract with appropriate force
at the desired moment requires an electrical impulse to be generated
through our nervous system. This CNS/muscular relationship can only
be improved by repetition of the specific movement. The relationship
between nerve impulse and muscular contraction is intensified under
the stress of relatively fast running. It's also obligatory to become
as muscularly efficient as possible in order to gain speed when
you're near your maximum effort. In a sense your body is being "forced"
to greater efficiency of movement because it's using all available
power to propel itself. Therefore during anaerobic efforts (the
speed of anaerobic efforts is not determined by oxygen processing
capability), any gains in speed must come from either an increase
in power, greater efficiency of movement, or both in unison.
You might respond, "But I've been told that my form will fall apart
when I train at high speeds." This is true if you push too hard, so that's why we do intervals with breaks in between so we
have time to regain our composure.
Psychological Adaptations to Speed
The faster you run, the more lactic acid is produced by your body.
Lactic acid is the single most limiting factor that deters us from
running even faster. When we subject ourselves to the burn of lactic
acid repeatedly, we build-up a tolerance for the sensation. Another
more subtle adaptation is that speed is perhaps more of an "addiction."
It feels good to move really fast under our own power, so we crave
more and more. Shall we put this particular addiction in the "productive"
or "destructive" category? You be the judge.
How Much Intensity is Appropriate?
Most of your intervals should be performed at about 90% of your
maximum heart rate. The longer intervals, (600 meters or longer),
will usually elicit a higher pulse. This is partially due to the
time lag or your heart's response to stress and the nature of the
interval; shorter repeats are more likely to become anaerobic and
therefore don't require as much oxygen transport (equaling a slightly
lower pulse rate). If your recovery period is determined by heart
rate, wait until you see a number between 65 to 70% of your maximum
heart rate before you start your next repetition.
Speedwork once a week is sufficient for most athletes. More often
is too stressful for all but the most resilient youngsters. But,
with track workouts separated by more than ten days, your body tends
to "forget" some of what it learned between workouts; a portion
of the speed previously gained is lost, and the residual soreness
in the days following speedwork returns.
How Long to Continue?
A build-up of six to eight weeks yields the maximum results. After
this amount of time, your improvement begins to level-off and the
risk of injury increases as you push for ever higher standards.
I recommend that you start your speed work about six weeks before
a competition that is a main focus of your season. Try to improve
your speed with each week. Then finish-up with a slightly easier
workout during the last week before the key race. After your Personal
Record race effort, take a couple weeks off from the intervals and
recharge your energy stores, both physically and mentally. It's
difficult for some athletes to take this time-off from the intense
workouts, but it really works well in the long run. Obviously, this
peak/rest cycle can only take place two, or perhaps three times
during a season, so timing is critical.
Our weeknight speed workout is very effective because there's always
someone close to your pace to run with. Doing this difficult type
of workout with others keeps you "honest" in the sense that you
can compare your efforts from week to week using others' performance
as a reference. The group can also keep us from doing too much,
because the collective wisdom of thirty or so experienced runners
is virtually impossible to disregard.