hoselpalooza

@iacas, i thought it was clear that dr. lynn was talking about the trail foot. isn't that what he's demonstrating with kevin chappell's swing here? though perhaps it would be better to refer to his published research which clearly mentions the trail foot: now that we've established "trail foot" is in play feel free to review what i've previously posted with an open mind. and for others following along, i think this is a pretty good overview of the forces involved that originate from the feet: https://www.youtube.com/watch?v=raaEMTKmNUU#t=1m43s no, i meant right. and obviously i agree with your feedback about using trail/lead instead. below is more info to support what i was talking about (from the swing catalyst 3d motion plate data guide). remember, we've already established the use of "trail foot" in the published literature as a source of GRF to create forward momentum so it should be clear by now i'm not "twisting" others' words or whatever you said: here's a good video demonstrating this: i cited dr. lynn's work earlier because swing catalyst is relevant here, but i could also cite research from kevin ball, russell best, and many others who talk about trail foot/leg/whatever GRF in the golf swing. or if you have some way to disprove trail foot/whatever push off with peer-reviewed, published research, i suggest you provide it. the videos @billchao and @saevel25 shared don't disprove anything, either. i thought the focus was supposed to be on elite golfers? and similarly the video @phillyk shared with chris como jumping off of a diving board does nothing to prove the absence of trail foot/leg GRF in the golf swing; it's a joke.

just so we're clear, you're saying that the PhD director of research at swing catalyst is wrong about this? do you want me to toss out more data published by other PhD's which supports the fact that golfers, to some extent, push off of their right side?

@iacas, you might want to re-up on your swing catalyst certification. source: https://carolinas.pga.com/wp-content/uploads/sites/3/2019/03/Dr.-Scott-Lynn-PhD-Swing-Catalyst.pdf

boditrak is one dimensional so it won't show forward translations (or push off). i just thought it was easy enough to see/extrapolate but apparently that's not the case for others. you should review the swing catalyst information i shared above, including the clip from the swing catalyst certification seminar taught by the PhD director of research. Of course it’s possible. But that’s not what’s happening. It’s also possible to shake your head violently during the backswing as well. i really should have phrased this differently. it's physically impossible to move the COP/COM toward the target without pushing off with the trail foot near the top of the backswing. it's just the extent to how much golfers push will vary depending on things like foot dominance, how they like to shift pressure, etc. again, don't take my word for it. just look at the information i've already posted. this is the closest somebody's come to acknowledging push off happens. thank you for braving the storm. 😂

you guys are comically wrong about this. literally everyone pushes off to the right to some extent because of physics. some golfers just do so more than others. "With sufficient traction between the golfer's feet and the surface, the horizontal force allows the golfer to push in one direction to move in the opposite direction (for example pushing to the right to move the body mass to the left at the beginning of the downswing for a right-handed golfer)." https://www.swingcatalyst.com/learning-center/articles/ground-reaction-force dr. scott lynn, PhD and research director at swing catalyst discussing pushing off of the trail foot during a swing catalyst certification course: some key points so you don't have to watch it all: 6:55 demonstrates pushing off of trail foot to shift COP/COM forward 8:24 demonstrates how kevin chappell pushes off with the trail foot at the top of the backswing to shift COP/COM forward https://www.youtube.com/watch?v=PCvLsgVtfjM#t=6m55s let's recap: - numerous tour-level pros and instructors mention the trail leg push off, many likening it to throwing a baseball. - sean foley, who uses swing catalyst and whose work with justin rose has been referenced by dr. lynn in certification courses, describes the push off as a "key source of power", and uses throwing a baseball as an analogy. https://www.youtube.com/watch?v=VWmUOyVa5hA - every single baseball pitcher pushes off of the mound because of physics. if you missed the swing catalyst certification video explaining the physics behind this or if you still don't believe pitchers push off, just google it. there are numerous scientific studies which incorporate force plate data to describe the horizontal force pitchers use to achieve forward translation (or push off). - and lastly, the research director for swing catalyst clearly demonstrates/explains how some elite golfers, kevin chappell in this case, push off of the ground with their trail foot toward the top of the backswing to move their COP/COM forward. and the swing catalyst website literally mentions how right-handed golfers push to the right to move the body mass to the left. @boogielicious, this is my favorite comment so far; i really appreciate your use of irony. because, you know, physics... ;)

after making bogus points easily refuted with data from the video you're still not making any sense. both of the pressure spikes which you said didn't exist are plain to see, which you admit, but you still refuse to believe those pressure spikes were caused by pushing off of the right foot. the data indicate this, the qualified professional performing the analysis indicates this, in another article kevin said he wants to feel this early in the downswing, and so on. are we having fun yet? /s

yes, he is. and later hashimoto explains his quick pressure shift forward as a result of the push off here. you missed the spike which occurs half a frame earlier. it moves from 68 -> 80. this is also incorrect. watch the video again. the pressure on the lead foot jumps from 20 -> 74.

kisner achieves 80% on his trail foot exactly at the top of the backswing. he starts pushing off just moments prior when pressure is at 68%.

reported as inappropriate. it's possible to make a lateral shift toward the target by pushing off with the trail foot before completing the backswing. i've shared data, analysis by qualified professionals, as well as comments from pros who all assert they push off of their trail foot during transition/early part of the downswing. if you guys want to continue to disagree with everything i've presented that is your prerogative, but it doesn't make you correct.

i did see it and you're completely wrong. like i said, pressure in his trail foot goes from 68 -> 80. look at these two time-stamped screenshots:

which is exactly what terry hashimoto demonstrates in the trace of kisner i shared. the trail foot pressure increases from 68 to 80 as he pushes off of his trail foot during transition. hashimoto later comments about how a lot of bodytrak advisers talk about how the pressure gets to the lead side quickly but that it starts from the trail side. what is the flaw in hashimoto's analysis?

my mistake about the left foot being unweighted. then what does this mean if not that the trail foot has to be at 100%?

first you say that it needs to be at 100% to indicate pushing and then when i show you something at 100% you say it's proof the trail foot is unweighted. seriously? and what about peak velocity? you're completely ignoring valid data as well as the analysis of other qualified professionals. and you're saying i'm trying to make 7 out of 2+2? this makes no sense.

also, the last trace shows 100%? if this isn't proof, what is?

this is comically wrong. are you saying that dr. satosho mckenzie, terry hashimoto, scott hamilton, etcetera, are reading the traces wrong? also, this is at 100%: this one video only demonstrates what's going on for that particular golfer. i never said that all golfers push off with their trail foot. the term i've seen is "peak velocity", and in the traces i've shared you will notice peak velocity occurs when the majority of pressure is still on the trail foot. this is what the analysts have said represents the pushing off move to shift pressure from the trail foot to the lead foot. more info from another source who uses force vectors: Push hard to get more acceleration | dbprogolf The ground reaction force (GRF) is the force exerted by the ground on a body in contact with it. Recalling Newton’s 3rd law: “For every action, there is an e...