Shitty landings might not hurt, but they can leave you with swollen knees, scrapes in places you’d rather not have them, etc. A friend of mine dislocated his shoulder on a bid.

I do agree that the takeoff is important-very important–but even so, bidder beware.

I think the lower center of gravity definitely has a role there…but then you have your shoulder-height bids which obviously involve a pretty significant fall, regardless of where the center of gravity starts.

Maybe I should be giving more credit to the upper body for helping to absorb some of that impact if it isn’t the slide that does it…

The key, of course, is that not everything else is the same. I believe the critical difference is that to get good horizontal explosion, you must lower your center of gravity significantly.

As a physics major with a background in karate, I’ll also put it out there that rolling diagonally across the back is a great way to absorb the impact. Learning to do so correctly is worth it, but the body positioning required means you can’t do it on a full-extension lay out, so sometimes you still gotta slide.

Back in my early bidding days I had one pretty similar to that. It’s a good thing I had a goatee to cover the scrape on my chin!

no slide. ouch

Fair enough.

You know, I almost dropped the “I’m not a physics major, but…” at the lead-in there.

How about, the fall-over bid has a component of torque to it that increases the vertical force component compared to a bid that explodes forward (so your body isn’t rotating towards the ground as much as the fall-over bid)? I do feel like torque comes into play at some point in this process, though.

Or perhaps it’s just the body mechanics of a good explosive bid that lowers one’s center of gravity that makes for a less painful landing. I don’t really have the grounding in thinking in terms of physics to be able to give more than theories.

I don’t buy this. Everything accelerates toward the ground at the same rate (ignoring air resistance which is not significant at these speeds), so the only factor that determines the vertical component of speed of impact is height + angle/speed of takeoff. Remember that the velocity of impact is just a vector summation of two components, perpendicular (to ground) velocity (verticle speed) and parallel velocity (horizontal speed). Increasing the horizontal speed (as you have said , by laying out at higher speeds) does nothing to reduce the vertical speed of impact and cannot reduce the overall speed of impact.

But as you mentioned, speed is not directly what determines the severity of impact, that has to do with the force applied to your body. There is a transfer of momentum from your body to the ground. The ground applies a certain impulse to your body, based on your speed of impact and weight. And since impulse is force*time, the longer the time the impact is spread over, the lower the force of the impact. But impulse is also a vector quantity, so more time sliding will reduce the horizontal force, but not the vertical force (as you have claimed). A muddy surface will reduce the vertical force however.

I don’t deny that (at least intuitively) layouts with at least some horizontal speed will hurt less than flopping straight down at the ground, but I don’t think it is for the reasons you have described.