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For testing reactive strength.... which is better? The traditional drop jump or the 10 to 5 Rebound Jump test? Like most things.... it depends. Both have different benefits & present different opportunities in testing & monitoring. A thread 
For me, the convenience & speed of 10 to 5 RBJT is one of a number of advantages
Short habituation period
Easy to cue short (<150ms) or long (<250ms) contacts depending on goal of test
(Relatively) low impact load
Quick turnaround btw athletes if testing large groups
Short habituation periodEasy to cue short (<150ms) or long (<250ms) contacts depending on goal of test(Relatively) low impact load Quick turnaround btw athletes if testing large groups
While research doesn't fully bear this out (yet), best guess is 10 to 5 RBJT is more strongly associated with late phase acceleration & top speed running performance due to high level of dynamic correspondence:
Upright posture
Low contact times
Cyclical / repeat action
Upright postureLow contact times Cyclical / repeat action
The 10-5 RBJT also appears v safe in implementation. Ultimately, athlete themselves is the "self-limiter". Impact loading is largely dictated by their own ability & output (how high they hop) so little chance of overload impact injury. Across 100s of tests, never seen an injury.
However, Drop Jumping provides unique opportunities to overload beyond an athletes "capacity". Increasing drop height allows opportunity to overload eccentric strength abilities which can often be differentiating factor in some sports.
Use of DJ might be more applicable where high-end eccentric strength qualities are of interest & may be more associated w/ high ecc actions: jump events, deceleration / COD etc. Likely see greater differentiation btw athletes at high drop heights who may be similar on 10-5 RBJT
