May 7, 2007
Aerobic Conditioning Testing for the Cross Country Skier
Summary: This two part article by Dain LaRoche is on functional aerobic tests that coaches and athletes can can use to determine baselines or changes in aerobic fitness for nordic skiing.
Aerobic Conditioning Testing for the Cross Country Skier
By-Dain LaRoche Ph.D.
Aerobic capacity or VO2max is the maximum amount of oxygen that the body can
take in and use to produce energy, and its importance to endurance performance
is not questioned. It is the product of the delivery of oxygen by the cardiovascular
system and the ability of the muscles to extract and use this oxygen to produce
energy. The higher the VO2max, the more physical work an athlete is capable
of and therefore the faster she/he can ski. Although VO2max can be measured
in the laboratory using specialized equipment, field estimates of aerobic capacity
are more convenient, are inexpensive, and therefore can be used routinely to
track athletic performance. Two field tests have been described below that should
be used every month or two to monitor the aerobic condition of your athletes,
one for the upper body and one for the lower body. Additionally, a morning heart
rate test is described that can be used to assess the long-term response to
training. Monitoring of environmental conditions, use of the same equipment
during rollerskiing and skiing, and consistency of test administration are paramount
to be able to track changes in performance over time.
One Kilometer Uphill Double Pole Time Trial
Both laboratory and field testing have consistently shown that upper body maximal
aerobic capacity and muscular endurance are strongly correlated to cross country
ski race performance (r = 0.75 to 0.92). In other words, those who perform best
on this test are likely to do well on the ski course. Despite this, aerobic
training and testing of the upper body is routinely neglected.
Equipment: GPS, wheel, or bicycle with computer to measure
one kilometer, 2-way radios, stop watch, heart rate monitor, lactate analyzer
(if available), cones or spray paint for start and finish lines, classic ski
or rollerski equipment.
Environment: 1 kilometer (0.62 miles) uphill of an approximately
consistent 5-10% grade
Methods:
1. At least two individuals are needed to administer the test, one to start
the athletes at the appropriate time, and one to record finish time, maximal
heart rate, and possibly lactate.
2. Athletes should be instructed that this is a race, there should be no pacing,
and that the should use double pole only (no striding, double pole kick, or
skating)
3. Athletes should be started at intervals of 1-2 minutes to allow time for
data collection at the finish.
4. Record maximal heart rate immediately after finishing, maximal lactate two
minutes after finishing (if a lactate analyzer is available), and time to complete
the course.
5. Improvements in performance can be demonstrated by a decrease in time, a
lower heart rate for the same time, and a decrease in maximal lactate for the
same time.
6. This test should be repeated every 1-2 months and it is essential that the
test be completed on the same section of road or ski trail, using the same equipment
each time, and ideally under similar environmental conditions.
Ways to Improve Performance:
*Athletes can perform double pole intervals of 1-5 minutes
in duration, for a total time of 5-20 minutes, at an intensity near lactate
threshold up to race pace (80-100% of maximum heart rate)
*Endurance double pole 20-60 minutes in duration at an intensity
below lactate threshold (60-80% of maximum heart rate)
*Kayaking, canoeing, swimming, rowing 30-180 minutes in duration
at an intensity below lactate threshold (60-80% of maximum heart rate)
Estimation of VO2max from 2,400m (1.5 mile) Run
Equipment: Stop watch, heart rate monitor, lactate analyzer
(if available)
Environment: 400m running track or 2,400m (1.5 mile) meter
marked course on flat terrain
Methods:
1. The athlete should run 2,400m as fast as possible (if using a 400 meter track,
six laps should be completed).
2. Athletes should be instructed that this is a race and there should be no
pacing.
3. Athletes may be interval or mass started depending on whether blood lactate
measurements will be obtained at completion.
4. Record maximal heart rate immediately after finishing, maximal lactate two
minutes after finishing (if a lactate analyzer is available), and time to complete
the course.
5. Improvements in performance can be demonstrated by a decrease in time, a
lower heart rate for the same time, and a decrease in maximal lactate for the
same time.
6. The following equation can be used to estimate VO2max by dividing 483 by
the athlete’s time in minutes and adding 3.5. To convert seconds to a
decimal, divide by 60, for example: A time of ten minutes and 25 seconds is
10 minutes plus 25seconds/60seconds per minute = 10.42 minutes. Therefore, VO2max
= 483/10.42 = 46.4 + 3.5 = 49.9ml/kg/min
.
VO2max (ml/kg/min) = 3.5 + 483 / (time in minutes)
Research has shown that elite female and male Nordic skiers usually have VO2max
levels of 55-75 ml/kg/min and 65-95 ml/kg/min respectively. World Cup Nordic
women competitors have VO2max values in the 60’s and low 70’s. Bjourn
Dahlie’s VO2max has been reported at 95ml/kg/min but most of his competitors
are in the 80’s or high 70’s. To be competitive at the Junior National
Level in the United States women should have VO2max values above 55ml/kg/min
and men should be above 65ml/kg/min.