“Step 3 ? Position your feet so the angle of the knee joint is approximately 100 degrees. This is an average value, no need for a goniometer. But, the knee joint must be greater than 90 degrees!”
Is the 100 degrees measured from a straight leg, or is it the angle between the thigh and shin bones while seated?
I’m hoping it’s the former measurement, because if it’s the latter, I’m officially a spaz!!!
Yes, it’s the angle between the thigh and shin while seated. It’s tough to maintain an angle >90 degrees but try anyhow.
OK, so I’m officially a spaz, because using the 6 inch in move my body wants to do a back flip, instead of going straight up. Seams like the lower the box, the higher the tendency for this to occur.
Do you (Chad) have any video, or photo sequence clips from the side?
Thanks for the help in advance!
I’m trying to decipher your last post. I think you are saying that you tend to jump backward, as opposed to straight up?
First, be sure you are using a box that is high enough (your hip and knee joints should be at 90 for the correct height of the jbs). From there, push your feet out slightly in order to open up your knee joint and allow for ~100 degrees of knee joint flexion. Your feet should be wider than shoulder width.
Most of the time when a trainee feels like he/she is going to do a “back flip,” it’s because the trunk isn’t flexed forward enough while seated on the box. Make sure your trunk is flexed forward while seated on the box before jumping up.
I guess that I’m using too low of a box (12"), and will have to add 3"-4" in order to comply to the 90 deg. between hip and knee.
I thought that the problem was something like that, because my center of mass felt too far behind my feet.
Thank you again for your replies.
Based on last night’s attempts I can see that the sbj will be of great benefit to my speed.