The debate is open again of how effective the testing of bowlers in lab
conditions. I will reproduce few excerpts from the ICC protocol and Dr Lloyd
report to give some insight.
From ICC protocol:
4.7 Every effort must be made to ensure that the player is bowling as close
to match pace as possible. This can be measured after each delivery if
equipment is available(Radar Gun), or measured via the 3D data during
analysis. If deliveries are not at a suitable speed(so as to represent match
conditions) then the data shall be invalid.
Note: There is no reason why the above analysis cannot be carried out during
a match condition.
4.5 In respect of a fast bowlers, four "normal - good length deliveries",
four "yorkers" and four "bouncers" must be recorded. Four deliveries of each
spin variation for the leg or off spin bowler must be recorded. Consultation
and feedback from the player and the coach is important as to the
reliability of each delivery.
4.6 3D analysis is to be calculated for each delivery.
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From Dr Lloyd report:
Thus, any three dimensional laboratory analysis must always be compared with
the two-dimensional video images collected during match play, albeit with
the limitation described above.
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Considering the above point, in my view, the lab tests are full
representation of match condition.
Ananda
The full ICC protocol:
4. Bowling Analysis (Indoors or Outdoors)
4.1 All assessment shall be carried out with the player bowling off his
normal full run-up, on a correct length cricket pitch.
4.2 A minimum of two synchronised high-speed cameras operating at a minimum
of 200 frames per second (250 maximum) to be used to collect the data.
Minimum Shutter Speed 1000Hz to prevent blurred images. The cameras and
computer to be operated and positioned in appropriate positions to
facilitate a subsequent three-dimensional analysis of the shoulder, elbow,
wrist and ball."
4.3 Calibration and accuracy procedure must be undertaken in the delivery
space prior to data collection. Accuracy analysis should be indicate that
the 3D methods employed are accuracy to within +/- 2 (Note: A solid iron
bar(1m in length), with markers representing the shoulder, elbow and wrist
can be used in calibration procedure. The rod must be rotated in the same
manner as a bowling arm)
4.4 Warm up(player's own) - but must include the bowling of a number of
deliveries at match pace prior to data collection. The player to have no
clothing on the torso, in order to enable manual digitisation of the joint
centres during the data collection period.
4.5 In respect of a fast bowlers, four "normal - good length deliveries",
four "yorkers" and four "bouncers" must be recorded. Four deliveries of each
spin variation for the leg or off spin bowler must be recorded. Consultation
and feedback from the player and the coach is important as to the
reliability of each delivery.
4.6 3D analysis is to be calculated for each delivery.
4.7 Every effort must be made to ensure that the player is bowling as close
to match pace as possible. This can be measured after each delivery if
equipment is available(Radar Gun), or measured via the 3D data during
analysis. If deliveries are not at a suitable speed(so as to represent match
conditions) then the data shall be invalid.
Note: There is no reason why the above analysis cannot be carried out during
a match condition.