Recently I’ve been doing a number of bowling analyses for some up and coming junior teenage fast bowlers. One thing that struck me was how often these young bowlers had their momentum mis-aligned through the delivery stride.
The most common problem was momentum heading towards fine leg at the beginning of the delivery stride (back foot landing), which often results in some sort of correction later in the delivery stride. Often this ‘correction’ is displayed as an excessive lateral flexion of the upper body to the off-side, to create a resultant ball trajectory at the batters stumps. This creates extra stress for the bowler, usually through their front hip joint, pelvis and/or lower back. Sometimes all three.
https://www.cricconnect.com/profile/683/pace-doctor/blog/2207/run-up-angle-and-jump-direction-ndash-are-they-important-for-fast-bowlers