This week we have seen Newcastle Knights rookie sensation, Kalyn Ponga ruled out of State of Origin 3 with a reported grade 1 lateral hamstring strain suffered against Canterbury over the weekend.
Backing up from a huge performance in Origin 2, Ponga sustained a somewhat innocuous injury early in the first half against the Bulldogs.
When do hamstring injuries occur?
Hamstring muscle injuries are a common injury in sports that involve high-speed running and kicking.
The biomechanics of hamstring injury
During maximal sprinting, the hamstrings work to decelerate the swinging shin bone and control the straightening of the knee. They then work as the foot hits the ground to help extend the hip.
Most hamstring injuries occur at the end of the swing phase when sprinting.
As was reported this week with Kalyn Ponga's injury - we usually see these injuries occur at the muscle-tendon junction of the outside hamstring muscle (biceps femoris).
Kalyn Ponga made 10x his season average for tackles per game in State of Origin 2
Some interesting stats out of Ponga's Origin performance came in his tackles made. Playing in the front-line, Ponga made a total of 29 tackles, approximately 43% of his total tackles made in 24 appearances for the Knights this year (68 tackles).
How much has this spike in workload contributed to Ponga's hamstring injury? I would love more data, however what we have seen from his Origin performance is a spike in acute workloads comparative to his chronic workloads at fullback.
Acute workload increases >1.5x = increased injury risk
We know from the work done by Tim Gabbett that acute workload spikes that exceed 1.5x chronic workloads (preceding 3-6 weeks) leads to an increased soft tissue injury risk in the following weeks.
Unfortunately, in Kalyn Ponga’s case, we have seen him sustain a grade 1 lateral hamstring strain and will likely miss 3-4 weeks of football, including State of Origin 3