32
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Test sequence
The subject makes the jump with help of the counter move-
ment. When the subject lands on the jump mat, the results for
the jump are calculated. If the subject does not land on the
jump mat, a
Too long jump
notification will be shown after a
brief period of time. The notification will also be shown if the
subject leaves the mat, since Powertimer assumes that the sub-
ject is currently jumping. If the
Too long jump
notification is
shown, the current jump is cancelled and no results are calcu-
lated.
After the subject has landed on the jump mat and the results
are calculated the subject needs to wait for at least one sec-
ond before starting her next jump. This timeout is needed to
filter away the extra on-mat and off-mat events that usual-
ly come from the jump mat when the subject lands on it. If the
subject starts his jump before the timeout has elapsed, nothing
will happen.
Test results
Powertimer
measures the jump time and calculates the follow-
ing results:
•
Jump Height
in centimeters or inches depending on the re-
gional settings.
•
Jump Power
in watts.
•
Elasticity
. Elasticity is calculated from the difference between
the best CMJ and
Static Jump
results made by the subject
within the same test session.
The best CMJ result is used in the
Repetitive Jump Speed-
Strength Endurance Capacity
calculation.
8.6 Drop Jump
Test description
The
Drop Jump
(DJ) is used to test and measure explosive
strength and stretch tolerance performance. In DJ the subject
starts his jump performance on a platform. The subject jumps
from the platform to the jump mat and then jumps as high as
possible.
Test parameters
Drop Jump
has two test parameters:
Jump Count
determines
the amount of jumps to be performed in one test action and
Drop Height
determines the drop height for the first jump. The
Drop Height
can be changed before a jump if needed by us-
ing the
Change Drop Height
action of the
Test Performer
view.
Test sequence
The subject drops from the platform to the jump mat and jumps
on the jump mat. After the subject lands on the mat the meas-
urement results are shown. When the subject leaves the jump
mat to climb back on the platform, the Powertimer assumes
that she is making a jump and shows the
Performing test
notifi-
cation. The “jump” gets cancelled after a brief period of time
and the subject can then perform a new drop jump.
Test results
Powertimer measures the jump and contact times and calcu-
lates the following results from them:
•
Jump Height
in centimeters or inches depending on the re-
gional settings.
•
Jump Power
in watts.
•
Relative Power
in watts.
•
Reactive Strength Index
from the relation between the con-
tact and jump times.
You can also view a graph of the relations between
Drop
Height
and
Jump Power
by selecting the
Drop-Power Curve
ac-
tion in the
Test Performer
view.
8.7 Illinois Agility Run
Test description
The
Illinois Agility Run
measures the subject’s ability to acceler-
ate, stop, change direction and then re-accelerate. This test is
a slalom course in which the total sprint time is measured.