Written on February 16, 2009 at 8:07 am, by Eric Cressey
The answer is both!
The question? “What do you test?”
My rationale is this: if you have a skinny athlete who adds 15 pounds during a two-month period, but his vertical jump stays the same, a VJ-only assessment protocol won’t tell you that he gained a ton of peak power.
As such, we use vertical jump in conjunction with body weight to calculate estimated peak power output using the Sayers equation. While recent research demonstrates that this equation typically underestimates peak power, the important thing for me is reproducibility (not complete accuracy).
As an example, last week, I posted a video of Tim Collins, a Cressey Performance athlete and Toronto Blue Jays prospect who vertical jumped 38.7 inches at his final test of the off-season.
More impressively, he went from 27.9″ on October 3 to 38.7 on February 4 while adding six pounds to his frame. Without factoring in the six-pound weight gain, we are looking at a 34.8% improvement in peak power. When we factor it in, though, it becomes a 37.2% mprovement. That 2.4% might seem insignificant to some, but the truth is that it’s an impressive result for an entire year’s hard work for many elite athletes with less window of adaptation ahead of them.
Vertical jump is a measure of relative power. Peak power is a measure of absolute power. Both have implications in the world of baseball, as you have to decelerate your body weight on each pitch, and you have to sprint, which is a function of the force you put into the ground relative to your body weight. Conversely, the push-off during pitching and the hitting motion are all about absolute power.
So, all things considered, you’ve got to track body weight and vertical jump, then plug them into an equation.
Hi..I do agree with this.. You keep rocking.Thanks for the excellent Hub!..keep going on with the good process..I was still wondering at your info’s ideas.Thanks for sharing the ideas.
The tuck at the end can influence this test because it’s based on time in the air or pad non contact time. A better way would be something like that found in “A simple method for measuring force, velocity and power output during a squat jump. (Samozino, Morin, Hintzy, & Belli)”. At least in my opinion.
May 8th, 2009 at 12:45 am
Hi..I do agree with this.. You keep rocking.Thanks for the excellent Hub!..keep going on with the good process..I was still wondering at your info’s ideas.Thanks for sharing the ideas.
May 14th, 2010 at 11:57 am
The tuck at the end can influence this test because it’s based on time in the air or pad non contact time. A better way would be something like that found in “A simple method for measuring force, velocity and power output during a squat jump. (Samozino, Morin, Hintzy, & Belli)”. At least in my opinion.
July 22nd, 2014 at 12:07 pm
Hi Cressey , thanks for share your thoughts.
Cressey which protocl you use to determinate power Lewis, Bosco, Sayers , Hartman formula etc..
July 22nd, 2014 at 5:10 pm
Rafael,
I like the Sayers equation.