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Swim Drafting vs. Bike drafting
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I was gonna post this as a reply under the "future of triathlon," but hopefully that thread is dead.

So....first of all does anyone have any real stats on the benefits of swim drafting and bike drafting? It seems to me that the coefficient of drag in the water is HUGE compared to air, even at speeds as slow as 4mph.

Second, I think the only reason why the drafting in swimming is a small advantage is that the swim leg is so short compared to the bike. Which leads me to.....

I just find it hard to believe that cyclists can find anything to complain about when a triathlon is almost always at least 50% cycling, 30%running, and at most 20% swimming. The normal argument is that if the disciplines were equal-timed there would be a disproportionate amount of energy used in the swim. But, I swear someone on the "future of triathlon" thread said that a 6-7 mile time trial on the bike is as hard as a draft-legal hour long race. If a 6-7 mile time trial is so tough, then why would a race that was 1mi swim (WR 14:3~), 7.5 mi bike, 5K run be so unfair?

As for the post about draft legal ironman, that will never happen, and I was definitely talking about 1:45min in an Olympic Distance. Drafting for 2.4 miles in a pack at Ironman, if done right, would probably save 5 minutes. But, the swim at Ironman doesn't even matter at the elite level. Everyone swims under an hour, most pros more like 50-52min. To train to swim under 45 minutes is a waste of time (60K+/week), when a triathlete with a strong swimming background can swim once a week and go 51.
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Re: Swim Drafting vs. Bike drafting [Kuendig] [ In reply to ]
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In Reply To:

I just find it hard to believe that cyclists can find anything to complain about when a triathlon is almost always at least 50% cycling, 30%running, and at most 20% swimming. The normal argument is that if the disciplines were equal-timed there would be a disproportionate amount of energy used in the swim. But, I swear someone on the "future of triathlon" thread said that a 6-7 mile time trial on the bike is as hard as a draft-legal hour long race. If a 6-7 mile time trial is so tough, then why would a race that was 1mi swim (WR 14:3~), 7.5 mi bike, 5K run be so unfair?


That would have been me (and the bike race was only ~18 miles @ 27+mph, so it only lasted about 40 minutes). The race you suggest would only be considered unfair to poor swimmers.

My idea of an "equalathon" would be the distances covered in 30 minutes at IM record pace. That translates to roughly 1.4mile swim, 12.5mile bike, and 4.75mile run. Ain't gonna happen.

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"Go yell at an M&M"
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Re: Swim Drafting vs. Bike drafting [klehner] [ In reply to ]
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I would love to see races with those proportions. The old Chuck's Tri in San Diego was 10k run, 20k bike, 2k swim. I realize no RD will do it in that order anymore but those distances were pretty balanced. A 25k bike would be even better.
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Re: Swim Drafting vs. Bike drafting [Kuendig] [ In reply to ]
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Find some results with splits for an accurate olympic distance non drafting race, and compare the time differences in the 3 disciplines between, say, the 95th percentile (ie 5th place out of 100) and the 55th percentile time (45th out of 100). It will vary a bit from course to course, from field to field, and depending on exactly where you set each of the two somewhat arbitrary performance levels (real good and not so good), but you'll find that the amount of TIME that separates a top performance from a mediocre performance is pretty similar across the disciplines. To me, that's a fair way to find the best triathlete. It's certainly more equitable than equal distance or equal raw time spent by the winner of each leg - skill vs. lack of it in each discipline will result in similar impacts on the final result.

As to why swim drafting is not perceived as nearly as beneficial as bike drafting, well, that's because it's not - yes the resistance of the water is huge...i think the reality is that it's SO huge that the water quickly fills in the gaps, stops moving, and and slows you down much more effectively than the air behind a rider will. You've got to be nearly as good as the person you are drafting on the swim to have a legitimate hope of staying close and getting a benefit for any substantial duration. A good swimmer can settle in behind another good swimmer and save what to them seems like a lot of energy, and it is, because they are staying more aerobic, but they aren't really going much faster than they could on their own. I can swim 60 minutes for 2.4 miles on my own, or have the good fortune to get on some perfect feet (assuming I can find them, and somehow know that they are just the right speed for my benefit) and go 58:30 and maybe be a little fresher at the end, but I'm never going to go 57 minutes even if Thorpe himself were to escort me with perfect pace.

On the bike the real world attainable energy savings are much more substantial. A drafter can ride way over their ability, really skewing the results. For that same ~60 minute effort one might pretty easily go 10 minutes faster, eg 65 minute 40K solo vs. 55 minutes in a pack or behind the perfect pacer.
Last edited by: skip: Sep 27, 05 15:58
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Re: Swim Drafting vs. Bike drafting [Kuendig] [ In reply to ]
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There was a triathlon back in the 80's on the east coast of the US I believe that had an equilateral format. Not sure what the exact distances where but you spend roughly equal time doing each sport in a swim/bike/run format. Indeed it would be interesting to try something like this today with a reasonable length of distances - something that a reasonably good male could do in roughly an hour. So that would be about 4K swim/40Kbike/16K run. Get a good cross range of top pro triathlon talent and see what happens. I say put some money in it and see what happens. LifeTime Fitness should try this format one year.

Drafting on the swim helps quite a bit and on the run too. Although, I believe that it's not as substantially helpful as drafting on the bike. Still, it seems a bit hypocritical to me to be able to draft like crazy on the swim and the run, but it's verboten on the bike! Note, I am not advocating drafting on the bike here just pointing out the odd hypocrisy of it all. If they wanted to truely run triathlons as an individual test of fitness( which many here and elsewhere seem to want them to be) then it should be time-trial starts for the whole thing and no drafting allowed anywhere on the course, swimming, biking or running!

Fleck


Steve Fleck @stevefleck | Blog
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Re: Swim Drafting vs. Bike drafting [Fleck] [ In reply to ]
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The race was done by Fletcher Hands in Oxford MD. It wa called the equlateral Triathlon - 4.8 miles swim, 18 mile run and a 50 mile bike.

I did the shortened version of it in 1985. It was a 2.4 swim, 18 run and 50 bike. It was a tough race.

DougStern
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Re: Swim Drafting vs. Bike drafting [DougStern] [ In reply to ]
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The race was done by Fletcher Hands in Oxford MD. It wa called the equlateral Triathlon - 4.8 miles swim, 18 mile run and a 50 mile bike.

I did the shortened version of it in 1985. It was a 2.4 swim, 18 run and 50 bike. It was a tough race.

DougStern
Fletcher Hanks. Did you ever do his No Run All Fun Biathlon (~2000yd swim/~14mi bike)?

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"Go yell at an M&M"
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Re: Swim Drafting vs. Bike drafting [klehner] [ In reply to ]
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I a m not sure but he was the race director of the swim across the Chesapeake (not sure of the spelling) River where there were very strong currents and many people had to be pulled out.

DougStern
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Re: Swim Drafting vs. Bike drafting [Kuendig] [ In reply to ]
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I think there are practical reasons for the relative shortness of the swim and the draft situation:

1. It is the most intimidating for most people there is a perception that more swimming would turn people away.

2. The swim portion is very labor intensive for the RDs, requiring lifeguards, etc. Long swims have slow swimmers in the water fro a long time. Depending on the roads this can be an issue on bike and run but can be reduced on rural roads. Swimming requires more close supervision.

3. Drafting is allowed in swimming because it would be extremely difficult to enforce drafting rules.
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Re: Swim Drafting vs. Bike drafting [Johnny99] [ In reply to ]
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Yeah, I didn't mean for my post to sound angry....was meant to be more sarcastic. Anyway, Im not a big advocate of drafting on the bike....I do it, because that's what the ITU rules are, but really, it doesn't make a big difference to me. I just wanted to point out that I hear cyclists "complaining" the most on this forum because of all the unfair rules such as drafting, when I think it should be the swimmers that have the biggest gripe.
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Re: Swim Drafting vs. Bike drafting [Kuendig] [ In reply to ]
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Thanks. As a slow swimmer and decent cyclist I'm not unbiased. If I had to race ITU things would be ugly. I'm afraid I'd miss the train. I have made some progress in swimming as the last few seasons there are more people around me. Maybe I've moved up to mediocre.
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Re: Swim Drafting vs. Bike drafting [Kuendig] [ In reply to ]
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Who said triathlon has to be fair? I did an informal poll on ST once to see what part of triathlon people hated the most. A couple of people asked why do tri’s if you hate one of the sports, but for the most part people chose either runner or swimming.



The people who hated swimming—I’m in this group, which was about 60 percent of the responders—were frustrated because hard work doesn’t necessarily make you faster. You really need a coach unless you just happen to be a natural fish. They also cited the boredom of swimming laps and the difficulty of finding a venue to train.



The people who didn’t like running cited injury issues and that fact that they were just slow.

Almost nobody had a problem with cycling—no surprise there—because it had cool gear to buy and was fun and practically injury free.

Given the numbers, you would think that more people would be into duathlon because there is no swim, but that is not the case. Hate the swim they might, but swimming is preferable to another painful run.



Chad



P.S. Agree with an earlier poster that drafting on the swim, bike and run are not remotely comparable. The swim is hard because you have to be fast and have to keep looking up to make sure they are still there. The draft on a run is negligible at best unless there is a pretty good breeze blowing. The bike is an entirely different matter. On a flat course I could ride at a Lance Armstrong Time trial speed for about five minutes, but if I was drafting him I could hang our for an hour or more on a good day. Riding solo past 30 miles per hour is an incredible feat. Drafting at that speed is hard but not superhuman by a long shot.
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Re: Swim Drafting vs. Bike drafting [cdw] [ In reply to ]
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[reply]P.S. Agree with an earlier poster that drafting on the swim, bike and run are not remotely comparable. [/reply]

I'd have to agree, having done a lot of swimming in pools with other people in my lane. The effect of someone going past you the other way is pretty substantial, but the actual draft doesn't help a huge amount. If I had to estimate, I'd probably save 5 minutes or so on the 2.4 miles. On the bike it would be more like 30 or 40 minutes. I did one race with about 20mph headwinds on the run, and drafting definitely helped there. Otherwise it's hard to put a number on a savings but I'd bet it's pretty darn low. So low at an 8 min pace with no wind to be insignificant.

I ride almost everything solo in training, and occasionally catch up with people out there. I am always amazed at how I have to push to go 23/24mph catching up with them but how trivially easy it is to go 20/21mph in a draft waiting for traffic to clear so I can pull alongside and say hi. It makes me wish I had a powertap so I could see what the actual difference is.


Mad
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