Watch the majority of runners as they gather for the start of a
race. How many of them are preparing their bodies as well as
their minds for the best
race possible? Probably not too many. Perhaps it's a little too cold to get out of the car, so they
keep the heater on, read the newspaper, and sip some coffee
before they leap out at the last minute
and plunge full tilt into the race. Or perhaps they find some
long-lost acquaintance and catch up on all the family news just
five minutes before race time, or
their shoelaces aren't tied quite right...and then they run a
slow, disappointing race.
Then watch the elite runners and notice what they are doing
to prepare. They're getting their entire body, especially their
cardiovascular system, ready
to race. How? By performing warm up routines designed to get
them to the starting line at their peak of readiness.
A proper warm up will raise the pulse to between 75-85% of
maximal heart rate. As the heart beats faster, it speeds the
delivery of blood and oxygen
to the leg muscles, which diminishes lactic acid production in
the early stages of a race. At the same time, the heart is
preparing for the stress of exertion. A
heart that is pumping at 140 beats per minute after a good warm
up is ready to absorb the stress of a pulse that jumps to 170 or
higher in the early stages of a
race.
The big problem with a good warm up is, however, that the
heart rate returns to normal very quickly after running is
ceased. Runners standing still at the
starting line for more than 90 seconds after a warm up will find
their pulse dropping by as much as 25%. This means that as soon
as they start racing, less
oxygen will be delivered to the leg muscles with a resulting
large dose of lactic acid, and more strain will be placed on the
heart.
To be most efficient, a warm up should last at least 10
minutes, which is enough time to increase the temperature within
the muscles and lower the
viscosity of the fluids inside, both of which make muscle
contractions more powerful. The warm up should be run at 60-80%
of 5K race pace, or 70-85% of
maximal heart rate. If the warm up is easier than this, the
cardiovascular system doesn't get a proper jump start; if the
warm up is faster, the runner risks tiring
early.
Warm ups for shorter events should differ from those for
marathons and other more moderately paced races. For the shorter
races, the warm up
should include a few 200-meter strides at close to race pace.
One benefit of strides is that the increased blood flow to the
legs causes tiny blood vessels
(capillaries) to dilate, thus increasing oxygen delivery to the
legs. However, as a marathon has lower oxygen demand, the warm
up need not include strides but
should consist of very easy running. One study has shown that 20
minutes of such easy running actually conserved leg-muscle
glycogen because it increased
the rate at which the leg muscles utilized fat.
So before you reach the starting line of your next race,
jog a little, stretch, then run at 70-75% of your maximal heart
rate for 10 minutes, including a
few 200-meter strides at your planned race pace if the race is
10 miles or shorter. When you get to the starting line, don't
stand still, but run in place until the
gun goes off. Your heart and muscles will thank you for your
concern.