How
to make a readiness monitoring using a simple wellness questionnaire.
Part 2
In
this part I am going to cover how to collect the data in the Excel and how to
numerically analyze it.
This
involves:
- Color-coding individual categories (fatigue, sleep...)
- Color-coding total score (sum of categories)
- A way for calculating base-line and trends using rolling average of the last six measurements
- How to calculate the difference of the current score to the individual tendency (which is calculated by rolling average)
Since
the wellness questionnaire is basically a nominal scale,
the method of calculating difference might be simple subtraction (Difference =
Current Score – Rolling Average). Other calculations that are based on ratio
scales might involve percent change (Difference[%] = (Current Score
– Rolling Average)/ Rolling Average x 100) or Z-score (Z-Score = (Current Score – Rolling Average)/Rolling
Standard Deviation) and all of these might vary on how you
calculate baseline, whether it is a
rolling average (what amount of measurements should be taken into account?), or
just plain average of all measurements, or even an average of measurements in
some period (for example pre-season).
Interesting
point is that calculating the baseline allows us to deal with players who score
higher-or-lower than normal, while calculating Z-scores allows us to deal with
players who show higher or lower variability in their scoring.
To be
clearer, we have three players who score:
Average
|
SD
|
CV
|
|||||||||
Athlete A
|
15
|
14
|
16
|
15
|
14
|
15
|
16
|
15,0
|
0,82
|
5%
|
|
Athlete B
|
10
|
9
|
11
|
10
|
9
|
10
|
11
|
10,0
|
0,82
|
8%
|
|
Athlete C
|
15
|
13
|
17
|
15
|
13
|
15
|
17
|
15,0
|
1,63
|
11%
|
Athlete A tends to always report lower scores, while Athlete B tends to always report higher scores. Calculating simple difference score (in this case score minus average) provides a method to deal with this scenario instead of relying on absolute numbers as a sign of reduced readiness.
Difference
|
|||||||
Athlete A
|
0
|
-1
|
1
|
0
|
-1
|
0
|
1
|
Athlete B
|
0
|
-1
|
1
|
0
|
-1
|
0
|
1
|
Athlete C
|
0
|
-2
|
2
|
0
|
-2
|
0
|
2
|
As you can see both Athlete A and Athlete B have same difference scores compared to their average (baseline). But what about Athlete C? He is always double.
Both
Athlete C and Athlete B have same average score (15), but way different
difference scores. What you can judge from the example is that for each change
in Athlete B’s score Athlete C scored double. Thus, Athlete C has higher variability in his scoring (see his SD
and CV).
As
some athletes tend to report normally higher-or-lower scores, some athletes
tend to have higher-or-lower variability as well. Does this means they are
automatically more or less ready to train, more or less tired? Not necessary
so. I guess we need to take into account their natural variability and find a
way to calculate it and take into account.
One
solution would be to use Z-score:
Z-score
|
|||||||
Athlete A
|
0,00
|
-1,22
|
1,22
|
0,00
|
-1,22
|
0,00
|
1,22
|
Athlete B
|
0,00
|
-1,22
|
1,22
|
0,00
|
-1,22
|
0,00
|
1,22
|
Athlete C
|
0,00
|
-1,22
|
1,22
|
0,00
|
-1,22
|
0,00
|
1,22
|
As you can see, all three athletes deviate the same from the average when we use the Z-score. Thus you see that none of them is more tired or more ready compared to whole group.
In
this installment I used simple difference score (since the wellness is based on
nominal scale and not ratio scale), but you can play around and implement
Z-scores. In that case you would need additional tab to calculate rolling SD
(standard deviation) the same way we calculated rolling averages. In that case GREEN zone might be from 0 to – 1SD, ORANGE zone from -1SD to -2SD and RED everything below -2SD.
For
more info I suggest checking the following papers from JASC (thanks to Dan
Baker for sending them)
Fatigue monitoring in high performance sport: A survey of current
trends.
J.
Aust. Strength Cond. 20(1)12-23. 201
Monitoring overtraining in athletes: A brief review and practical
applications for strength and conditioning coaches. J. Aust. Strength Cond. 20(2)39-51.
2012
In the next
installment I will cover one simple way to visualize this for better decision
making, along with designing a very simple dashboard.
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