This is a guest article from Max Andrews

How many coaches do you hear saying to "not fall over", "get side on", or "your arm is pulling away"?

Too many I reckon.

Have any coaches taught you how to utilise your legs effectively? I would be willing to bet they haven’t.

But, why listen to me when coaches have been using conventional wisdom for years?

Let's talk science.

A study called, How do our ‘Quicks’ Generate Pace? A Cross-Sectional Analysis of the Cricket Australia Pace Pathway revealed that a faster run-up had the potential to generate higher front foot braking forces by maintaining a strong front leg at front foot landing. In other words, bowlers who could transfer more momentum into their front leg and then stabilise and extended the front leg before release achieved greater ball speeds. This movement is also called bracing of the front leg.

Two others studies, one conducted at University of Sydney and the other at Johns Hopkins University confirmed that driving and braking forces in the legs of an athlete converted to greater energy transferred to the ball. The results from the first study said,

“the leg-spin bowlers measured significantly greater vertical and horizontal braking forces. Greater force during this phase of the action potentially allows for a larger transfer of energy to the hand. This may partially explain the larger spin rate of the leg-spin group.”

Findings of the second study supported the discoveries of the previous study,

“the athletes were found to generate shear forces of 0.35 body weight in the direction of the delivery with the rear leg.”

In order to achieve this, the bowler must align their force vector in a linear direction. Succeeding this production of force, it was found,

“the bowler must be able to resist forces of 0.72 body weight with the front leg. Landing vertical forces are gradually built up after foot contact to approximately 1.5 body weight, peaking just before ball release. Wrist velocity was found to correlate highly with increased leg drive.”

To put this in layman's terms, the bowlers who applied more force into the ground had greater potential to bowl and spin the ball faster.

Aligning the direction of force in the back leg towards the target enabled bowlers to produce greater force at front foot contact. In order to maximise this force production, the bowler must stabilise their front leg before extending it, this is why the forces are said to be gradually built up.

If this is executed correctly, the bowler will bowl off a braced front leg and all the force generated from the ground is transferred into the upper body and ultimately into the ball.

In a previous article, of mine, I spoke about hip to shoulder separation. I said that bowlers generate their energy from their legs, and then the energy is transferred to their hips, which rotate first followed by their shoulders. This movement has the potential to create a huge amount of core torque, think of it as pulling on a rubber band. The hips are being pulled in the opposite direction to the shoulders, thus when the shoulders begin to rotate, it is essentially the same as the rubber band being unleashed and all the force is then transferred into the ball.

References

• E. Phillips, M. Portus, K. Davids, N. Brown and I. Renshaw, "How do our ‘Quicks’ Generate Pace? A Cross-Sectional Analysis of the Cricket Australia Pace Pathway", Conference of Science, Medicine & Coaching in Cricket 2010, vol. 1, no. 1, p. 119, 2010.
• A. Beach, R. Ferdinands and P. Sinclair, "The kinematic differences between off-spin and leg-spin bowling in cricket", Sports Biomechanics, vol. 15, no. 3, pp. 295-313, 2016.
• B. MacWilliams, T. Choi, M. Perezous, E. Chao and E. McFarland, "Characteristic Ground-Reaction Forces in Baseball Pitching", The American Journal of Sports Medicine, vol. 26, no. 1, pp. 66, 68, 70, 1998.