Saturday, February 26, 2011

Going faster in shorter races - esp. if you are of larger build

A mate from my local forum hangout [steamroller] recently asked a couple of questions regarding going fast in shorter races, particular for the bigger blokes.

Q. I was wondering what the benefits would be for each piece of technology, specifically in relation to bigger bodies over a sprint distance triathlon.

I am a BOP [Back of Pack] participant and will probably always be down that end. In saying that I would still like to get faster over the sprint distance. Prior to everyone saying do more training and lose weight, I already understand that and have taken steps in that direction. I am specifically talking about improvements in transitions and also the use of technology i.e aero helmets, wetsuits etc.

I have read the stuff that fishboy did regarding the aero helmets,wheels etc but was wondering if the results he got would be significantly different based on greater weight and width regarding shoulders stomach etc.


I think steamroller was referring to: http://fishboy.triathlete.com.au/2009/11/v...el-testing.html when he asked his question.

So how can we squeeze a few savings off a short race time without actually doing much for it, particularly if you're bigger than the average bear?

I'm big-ish, but not Clydie* big - 81kg (180lbs) and 186cm (6 ft 2in), 55cm shoulder width, 100cm chest circumference. However, big enough that first time in the wind tunnel I was worse than an average triathlete (CdA 0.265-0.275 seems to be pretty on the mark average for someone with aero lid and bars, I was 0.285 with aero lid and aero wheels, and not much changed in the course of that wind tunnel session 1).

[* Clydie = local dialect for "Clydesdale category" (after the horse), in which the triathlon participant must be over 100kg (221 lbs).]

Being bigger means you have more frontal area that you have to either hide or somehow disguise as a slippery-as-a-fish shape.

Sprint is all about high speed racing... therefore being aero, and powerful as well, is crucial to success on a Sprint bike leg (20km or 12.4 mi of pain). Forget comfort, find the smallest possible slippery shape you can squash your body into, train to adapt to that shape and deliver race power in that position. Learn how to unpretzel yourself off the bike and "still run good" (I haven't quite mastered that bit yet).

You can throw tech dollars at the solution, but getting the body aero is usually the single biggest thing you can do followed by an aero helmet.

The time savings below are based on a 36kmh (22.5mph) average sprint bike speed using the same power, if you do just that *one* thing listed below.

Unfortunately you can't add all the time savings together - it doesn't work like that.... as you go faster, you save less total time.

Bike:
Aero lid (fishboy mandatory, and independent of body size): Steamroller had possibly the best aero helmet (Limar Chrono), but hadn't actually used it in a race!! Get it on the road son: wear it, you will PB next race.
A good aero helmet can make about 1.0kmh (0.6mph) speed difference: 54 sec (at 30kmh (18.7mph) the difference in speed is about 27 sec.)
A not so good aero helmet will increase your speed around 0.5kmh (0.3 mph): 27 sec saved over a road helmet - still a cool saving.
Below 26-28kmh (16.8 mph) the benefit of an aero lid is relatively negligible, and you may probably start feeling silly...so just wear your road lid if you feel like riding that slow.

Aero bars (or getting away from road position into TT position, this is dependant on body shape, flexibility etc) will generate a 1kmh (0.6 mph) speed increase: 54 sec saved

Aero wheels (independent of body size): 30-45 sec
Simkins aero brake (independant of body size): 8 sec saved
No front brake (illegal but what the hell) (independant of body size): 16 sec saved

So in essence you can get an array of bike time savings by just investing $$$ independant of body size.

You will however need some assistance to fine tune a larger body to go quick.
Though it sounds expensive, if you can get into a wind tunnel with someone who knows their schizzam from their elbow, or do field testing with power (also expensive if you have not a power meter) this is probably the best way of return on investment (see graph in the article mentioned above, you can spend loads of $$$$$$$ on bike bling and not be much faster than you already were).

Based on my starting and final aero setup I've saved 1:51 over 20km (12.4 mi) based on same input power, by tweaking body position and some specific aero hardware bits.

Swim:
For me, a wetsuit saves about 6-8 sec/100m, and takes ~8 sec to remove. Given a bit slower running in the wetsuit the break even point for me is around 300m swim (0.18 mi). Longer, than that I'll definitely have a suit on. If you are big, and sink like the proverbial, it may save more you than this.

Transitions:
Time can be had left, right and centre if you practise, practise, practise. None of these seem to be body shape dependent. Here's a bunch of stuff that I've worked out is faster for me. It might, or might not be for you. ;)

1. Walk through all transitions before the race. Work out swim entry, bike exit, bike entry, run exit and shortest distance, and physically walk/jog round them all so you see what it looks like in the race (nothing like seeing it before hand). Look for shortest route and landmarks. Remember aisle row markers "I'm between 13 and 14". Getting lost is sure fire way to add seconds.

2. Set up your gear carefully, in the same setup as you practice your transitions with (not practicing transitions? - tsk - better get on that too). Mine is towel folded, running shoes at bottom of towel, helmet top side down at top of towel, straps out in the right orientation for pick up and straight to head. Sun glasses open inside helmet ready for straight to head. Shoes clipped on bike (R shoe on R pedal and L shoe on L pedal, not as I have done once the other way :blush: ), appropriate gear pre-selected for bike exit.

3. Practice getting out of that wetsuit: get out of water, get running for a bit (recover from shock of standing up, and move faster for a bit), then try to remove wetsuit top - after top is down remove cap and goggles and finish run to bike. Practice removing wetsuit quickly after every open water practice swim - experiment with oil/glide substance on calves and feet to get feet out easier. As you arrive at bike, bend down pushing wetsuit as low as possible on legs, grab glasses put on, grab helmet and put on; at the same time stomp feet alternatively to remove suit; once helmet clipped, use hands to remove any last bit of suit and get bike off rack and go. A good 20 sec to be had here with practice.

4. Shoes on bike, run barefoot. Easily 15 sec saved in transition, you may give up some on the road getting your feet in, but you are at speed (yes, accelerate up to at least 30-35kmh before trying to put feet in, to go fast enough to minimise time loss).

5. Practice mounting. Keep running till the road is clear enough for a fast running mount, sometimes this may be past the mount line - run through the slower traffic, get to the front, quick mount and away up to speed before trying to get feet in. Another 5 or so sec saved.

6. Practice dismounting. Feet out of shoes resting on shoe tops in last 300m, hands on brakes decelerating on approach to line, swing leg over before you get to dismount line and leap into run on the dismount line. If you race long, and have bottles on the back - take 'em off - you don't need that much fluid, and it is a lot more aero without them, and worse, rear bottles can be a serious dismounting hazard as you swing a leg off the back of the bike.
If coming in overcooked, use a bit of brake and support a bit of weight on the front wheel between strides to get down to an actual running speed that your (now detonated) legs can cope with. I find acknowledging marshal at dismount line by nodding that you understand that you will be dismounting (or attempting to not crash and burn) leads to less yelling on their part. Very satisfying when you come in hot and they're gobsmacked you can actually be off the bike and through dismount that fast. Another 8-10 sec saved.

7. Get running quick - try and stand up as tall as you can and keep cadence high as you (try) to get into decent run form. It's hard, and I suck at it. There are many other better qualified runners than me that might have a few more pointers there.

Run:
There is no magic bullet (or else I would have found it by now). Sorry.

Actually - make sure you put glide or vaseline on parts of your feet pre-race you are prone to blister in... I wouldn't use socks in Sprint or Olympic race, but would for a long course or half ironman.

So there you have it, a few time savings that you can (hopefully) squeeze out of your next short race, independent of the fact you block the sun from most people standing next to you. Enjoy!

1 comment:

  1. It all boils down to consistent rigorous practices and tests, only then can you condition yourself to the discipline required for triathlons.

    ReplyDelete