Pro Triathlete and TI Coach Darbi Roberts pr's IM Arizona - How'd She Do it?

[descending]

Originally Posted by Zenturtle

Feel a bit guilty being so critical while being only an average swimmer myself, but I love swimming along mentally with footage of other swimmers and see how it compares to my own swim perception. Its a great learning tool.
Sometimes you are working on a small detail in the stroke and start to focus also on it in other peoples strokes.
Some are doing this detail the same, other move differently. You stat to get more aware of that detail in general.
Its the same when learning to play a musical instrument, or starting to take better photos. You listen to music differently than before, you frame the world diferently than before.
I think I am moving very slowly into the direction of this stroke on a good day when everything comes together because it feels pretty familiar swimming along mentally.
Cant regognize myself in the beginner stroke anymore, although there are bad setbacks occasionally.
Its definitly hard to learn it as an adult.

I don't think it's being critical in a bad sense. You are merely stating the obvious differences. If you are challenging yourself to get more flexible, swimming faster/longer/harder and being able to work within that new range of motion then graduating to new mechanics is a very real possibility. It's not an accident you see the front of pack swimmers using this woman's front end mechanics. It's potentially very fast if you take the time to explore it and ingrain it. Problem is it won't find you by accident you have to search and work towards it. I fully accept there may come a day I cannot utilize a shallow extension, catch and pull as Father Time catches up. I think I can keep it going for a long time b/c we have people in their late 60's who have amazing strokes on our team. I'm going to fight off the flexibility monster as long as I can!

[CoachStuartMcDougal]

Originally Posted by descending

I thought I detected a little bit of twitch, not a full blown 6 beat, but keeping in contact. I'd suspect she has a long history of swimming in her pedigree.

That's a 4bk that comes and goes - but I suspect that's mostly due to swimming at slower tempo. Darbi notes in the video, she's been swimming since the age of three and is her strongest leg, at least coming into triathlon. I assume a competitive swimmer, swim team, youth through college years.

Given the pace they're swimming at 1:22 100y pace (Suzanne I'm assuming yards - correct?). That around 14 spl, stroke length around 48" or 4'. That pace would put them at 59 min 2.4 mile swim. Given (and assuming) stroke length is a priority over stroke rate, to swim 52 mins in 2.4 miles at IMAZ, Darbi's turnover rate was between 60-63 strokes per min or 1.00 - 0.95 seconds per stroke and holding a slightly lower stroke length at 46" which puts her right at 52:00 for the 2.4 IM swim.

Darbi certainly has a beautiful stroke, and clearly one that holds up for long distance swims with minimum effort.

Originally Posted by WFEGb

NEVER! We do need her in Europe!

Best regards,
Werner

Haa! Well, we'll see about that Werner. I've already started lobbying for Tracey to LA!

Stuart

[descending]

Originally Posted by CoachStuartMcDougal

That's a 4bk that comes and goes - but I suspect that's mostly due to swimming at slower tempo. Darbi notes in the video, she's been swimming since the age of three and is her strongest leg, at least coming into triathlon. I assume a competitive swimmer, swim team, youth through college years.

Given the pace they're swimming at 1:22 100y pace (Suzanne I'm assuming yards - correct?). That around 14 spl, stroke length around 48" or 4'. That pace would put them at 59 min 2.4 mile swim. Given (and assuming) stroke length is a priority over stroke rate, to swim 52 mins in 2.4 miles at IMAZ, Darbi's turnover rate was between 60-63 strokes per min or 1.00 - 0.95 seconds per stroke and holding a slightly lower stroke length at 46" which puts her right at 52:00 for the 2.4 IM swim.

Darbi certainly has a beautiful stroke, and clearly one that holds up for long distance swims with minimum effort.



Haa! Well, we'll see about that Werner. I've already started lobbying for Tracey to LA!

Stuart

Maybe you can help me understand the calcs a bit I'm a little confused how you translate the spl assumption when they are not swimming a full 25 yards. They have accelerations off the wall and streamlines. That is worth a full 2 strokes from where they are breaking out, plus the pace is always faster off a wall. Not to mention the added distance everyone swims in open water between buoys it adds up over 2.4 no matter how good the sighting happens to be.

I could see the calculations transferring if someone swam in a perfectly straight line, had no slowing due to sighting, no slowing due to space/competitors, no slowing due to wind. If the swimmer deviates at all from a pool black line swim then they have to make up for that somehow. Does her stroke length get even longer in the open water?

What would the stroke rate need to be to hit a 51 with 16 spl?

[CoachStuartMcDougal]

Hi Desc:

Sure - just math R=D/T, or in a swimming context Pace = SL/Tempo (seconds per stroke).

SPL is a bit too broad and is based on true stroked yards excluding the glide off the wall. In the video, Darbi/Terry begin stroking at the 5y flags, so swimming a true (or very close to) 20 yards. SL = SPL/Dist, 20y/15spl = 1.33 yards or 4 ft. Roughly moving forward 70% of her height on each stroke - a very good "green zone". Using 16spl, given a 5y glide off the wall SL = 20y/16spl = 1.25y or 3.75 ft.

To hit ~51 mins at a SL of 3.75 ft:

Pace = 1.25y/.91 = 1.381 yards per second
100y pace = 100y/1.381=72.4 secs or 1:12.4
2.4 miles (4224y) = 4224y/1.381 = 3059 secs or 50.98 mins.

Yes those that sight forward more frequently will swim slower since they step on the brakes more frequently. But good open water swimmers use lateral targets when breathing and sight forward less frequently, 30 maybe 40 strokes before picking the head up to sight forward. It is a skill to swim very straight without constant visual adjustment.

Yes, my IM swimmers generally swim .1, .2 miles longer and that is a factor. Wind and currents absolutely. IMAZ little to no wind, it's in a man made lake, no current. Pros get the advantage of swimming in front the pack with no bottlenecks. There's also the wetsuit factor, stroke length will increase a bit. I use the math to get a good baseline then factor for each swimmer given their skill set and open water skill set when predicting/estimating swim times

I think since Darbi hung on to another swimmers wheelhouse for most of the swim, she probably slowed tempo a bit and increased stroke length, saving even more energy. Being they're pros, elite swimmers, in front of the pack, they swam closer to 2.4 miles than the rest of the triathletes.

Hope that helps a bit, but it's just using a little math.

Stuart

[descending]

Ok that makes sense thanks for that explanation.

Very impressive. Let me know if you ever come across any of her race footage at that pace please I'd love to digest some of that video!

[CoachSuzanne]

She just did IM South Africa today/yesterday there may be women's pro start footage online