Why is Bumrah breaking down so often despite not playing regularly?

A 'routine' radiological screening after returning from the Caribbean in 2019 had revealed a 'minor stress fracture in the lower back'—according to the BCCI media release—that ultimately ruled Jasprit Bumrah out of the home Test series against South Africa. He next played three months later, in New Zealand in early 2020. Cut to August this year and Bumrah missed the Asia Cup because of a back injury. A month later, Bumrah was ruled out of the ongoing series against South Africa, again because of a back injury, making him doubtful for the T20 World Cup.

What exactly is ailing Bumrah? Why is he breaking down so often despite not playing regularly? We took the help of Dr René Ferdinands from the University of Sydney, considered a leading expert in the world in cricket biomechanics, to understand. Ferdinands researches the biomechanics of fast bowling and has worked as consultant at the National Cricket Academy (NCA) in Bengaluru, New Zealand Cricket and Sri Lanka. His research was an important factor in the development of the current ICC bowling legality measures.

At the very beginning, Ferdinands seeks to debunk the accepted theory of fast bowling. "It gives a false sense of security to suggest that if all body joints move in the direction of the target, if such a thing were possible, that the fast bowler optimises the transfer of momentum from the run-up into the bowling action and minimises the risk of sustaining lumbar injury," he said in an interview.

"As an example, an observation of Bumrah's action will show his feet pointing towards the target with the pelvis and shoulders open, also facing in the general direction of the target. The theory is that from this point onwards, all joints should move in a straight line towards the target, so that the primary contributors to velocity are thoracic and lumbar flexion and rotation of the bowling arm in the vertical plane.

"The difficulty with this proposition is that it does not consider that most, if not all, bowling actions are a complex blend of thoracic lateral bending, flexion-extension, and rotation with varying degrees of pelvic lateral tilt, anterior-posterior tilt, and rotation."

Simply put, the human body can't be in total alignment to generate the kind of pace a fast bowler normally does. Bumrah's early delivery stride too shows a thoracic lateral bending and distinct pelvic tilt. It's not uncommon as well. Over the years, fast bowlers have come up with different technical adjustments that may have served to stabilise their bowling action so that maximum velocity contributions could be gained from the upper and lower body segments while maintaining relatively safe planar relationships between the thoracic and lumbar spines. Garry Sobers, Malcolm Marshall, Frank Tyson and Merv Hughes, for example, successfully used curved or angled run-ups. The flexed front knee was exploited to a great effect by Wasim Akram, Marshall, Dennis Lillee, Devon Malcolm and Kapil Dev.

Bumrah is different. He uses a front-on action with both feet pointing to the intended target line but does not seem to be able to maintain a relatively safe planar alignment between thorax and lumbar spines. "As the thorax laterally bends the pelvis is rotating on a horizontal plane, and the rear leg is driving towards the target, causing the vertebral spine to curve in an S-shape," says Ferdinands. "All this happens in a very short period, and is not visible to the naked eye. The question should be asked whether the rapid and repetitive loading of the lumbar spine in this configuration, while ground reaction forces are high, is a causal factor for Bumrah's stress fractures."

Pat Cummins faced something similar when he was starting his career. But he was in his teens then. Bumrah is 28. The bowling arm contributes to complication as well. Freeze the frames where he is releasing the ball and you will see how Bumrah's bowling arm is held well away from the body during its early downswing and sharply becomes more vertical on the upswing, effectively passing beyond the vertical at ball release. "The lateral bending of the thorax is required to accommodate the "above-the-vertical bowling arm" as the ball release is approached," says Ferdinands, who believes the release action is part of the reason why Bumrah struggles to establish a more planar relationship between the thoracic and lumbar spines.

Bumrah's bowling mechanics seems to be more compatible with a more side-on technique but remedial action at this age is not advisable, says Ferdinands. "It would be very unlikely that any technical intervention would reduce that S-curve in his spine. The execution of his bowling technique is now automatic. Any small change can adversely affect the dynamics of his entire action," he says.

"It is possible that Bumrah's action can imperceptibly stabilise over time, so that he is less susceptible to lumbar spine injuries." Till that happens, regular MRI scans and strict workload monitoring could be the only options to prevent another similar breakdown.