Interlimb kinetic asymmetries during the tuck jump assessment are more exposed following kinetic stabilization.
Lucy S Kember, Gregory D Myer, Rhodri S Lloyd
PMID 38593626WHAT IT FOUND
In 25 healthy female athletes, some limb force differences during repeated tuck jumps became more apparent after the jump pattern stabilized.
Many other force measures did not change.
Key findings
01Force differences between limbs increased after the jumping pattern stabilized for peak vertical ground reaction force, relative leg stiffness, average loading rate, total impulse, propulsive impulse, and peak braking and propulsive force.
02The athletes performed 15 jumping cycles on average, and the jumping pattern stabilized by the 9th cycle.
03Continuous force-time analysis found a small region of difference between limbs in the later part of ground contact, at 77-98% of ground contact before stabilization and 83-99% after stabilization.
STILL TO COME
How it was doneWhat they foundWhat it means for PTs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The study was cross-sectional, so it cannot show that these asymmetries caused injury or changed over time. The participants were all female athletes, and the group included 3 football players, 20 netball players, and 2 basketball players, so the paper does not show how broadly the results apply to other athlete groups. The analysis looked only at forces, so it is unclear whether joint movement differences between limbs would also appear. The authors caution that the 10-15% asymmetry thresholds are based on limited prospective data linking them to injury. Research on asymmetries before and after kinetic stabilization is limited, so definitive conclusions are not possible.
The easy way to misread this
Do not read the post-stabilization asymmetry increase as evidence that the tuck jump causes injury or that any intervention will reduce it. This was a cross-sectional test of 25 healthy female athletes, and the authors say the injury-risk thresholds are based on limited prospective data.