I was rather disappointed with this book because it didn't cover a lot of the physiology involved with performing at peak speeds. It was fairly mechanical in nature and while it was complete from a physics standpoint, it didn't apply the physical concepts to the practice of triathlon to the extent I was expecting. In sum, the book's final chapter is really all I needed to read.
The book was helpful in some ways though, and there are a number of things I want to employ from this book. I am recording them here so I remember them:
1. Swim: Triathletes should try to keep as much of their body out of the water as possible. This reduces drag, since there is more drag in the water than in the air. Wet suits aid in keeping an athlete near the water's surface, so maybe this is what the author is talking about. Otherwise, I'm having trouble visualizing a swimmer exposing a lot of his body surface to the air while still maintaining a good swimming posture and form. Indeed, wearing a wet suit decreases drag by 10% and has been shown to save a swimmer enough energy to increase cycling efficiency by 12%. Wet suit thickness between 3 and 5 mm is best, as the thicker the suit, the greater the buoyancy. My wet suit is 1.5 mm in the arms, 3 mm in the torso, and 4 mm in the legs.
2. Swim: Pressure drag is the most significant element (80%) of total drag, so a swimmer should minimize the surface first passing through the water. This means streamlined arms while gliding. This means a horizontal body position to reduce the amount of surface traveling perpendicular to the water. This means kicking from the hips to keep the legs from producing too much extra drag.
3. Swim: technique matters. The career swimmers are faster than triathletes because they place their arms, legs, head, and torso precisely in the most efficient positions. It's not brute strength; rather, it is body position that ultimate produces the most propulsion. I will set up a swim lesson with Josh to polish up my freestyle stroke. There is a note here that strong swimmers are actually faster in wet suits without sleeves because the sleeves alter arm position. I own a fully sleeved wet suit and I like it a lot. Even though I am a stronger-than-average swimmer, I won't get a new suit.
4. Swim: Most propulsion comes from the arms (not legs). Ways to produce the most speed include faster arm movement underwater and increasing the surface area of your hands by separating fingers by about 8 millimeters. I already spread my fingers, so no adjustment is needed in this area. As for faster arm movements, I think Josh has told me to do that. It's worth trying. This does not necessarily mean a faster stroke rate, though. I can still glide between strokes, assuming I can minimize pressure drag during the glide. A wet suit actually helps reduce stroke cadence by 14%.
5. Swim: Drag can be substantially (20%) reduced by dragging other swimmers. This can be accomplished in two ways. First, you can follow another swimmer directly behind, which is best, but also hard to do because you really have to tailgate them (your arms enter the space just behind their kick). Second, you can be offset 1 meter next to them, so that your hands are in the same line as the first swimmer's shoulders. I can definitely do this, but only if the two of us can swim in a straight line (and I'm not good at that).
6. Swim: Data show that if I go all-out on the swim, I'm likely to suffer on the bike later. Slowing down to 80-85% swim effort can avoid this effect. I will try to remember this strategy, since I tend to go as fast as I can during the swim.
7. Swim: Just a note relating to my swimsuit choice for competition: tighter fit is better because it limits muscle deformation, which reduces drag.
8. Bike: Make sure your bike is in excellent working order because this segment represents the greatest time investment during the race. I will do what I can with maintenance during the cycling season and, if necessary, take the bike into the shop a couple weeks before my Ironman to attend to any last maintenance or adjustments.
9. Bike: Strong legs are much more important than a "fast bike," so spend money on what makes YOU faster, not what makes your bike faster. The author uses this to make the case for training with a power meter, since it will teach me the level of effort necessary to produce the most force under various road conditions. It will also protect me from overworking my engine and burning out too quickly. I looked up the price of a power meter, and I don't see many options below $700, which is half the price of a new bike. I don't find this a reasonable purchase because heart rate and pedal cadence can be used to gauge my level of effort. Indeed, I recently read in another source that heart rate is a direct correlate of oxygen consumption, which itself a direct correlate of power generation. The book also notes that Strava can take the bike GPS data and calculate power for a ride segment, after the fact. I looked into this, and it is not true. If you don't use a power meter on your bike, all Strava will do is give you your average power per ride. This would give me a single number, and I don't think that's useful. In sum, I will take HR training very seriously as I do bike training, because I can monitor HR during my ride and try to keep it as consistent as possible. This is pretty much what power is use for: consistency in effort.
10: Bike: A lot of people are concerned about the weight of their bike and components. However, the human rider represents the greatest proportion of weight, so to experience the best gains in speed and power, a rider should lose weight when appropriate. Even 2-3 pounds of bike weight does not save much race time (maybe 5 seconds per mile at a 4% grade...which is fairly steep), particularly on flat race courses. Conclusion: lose body weight instead of bike weight, and really, none of this is as important as reducing drag.
11. Aerodynamic drag is reduced considerably at speeds more than 15 mph when one transitions from the hoods to the drops of a road bike. Further reduction in drag is very significant at 20 mph when one transitions from the drops to the aerobars, pulling arms in, and curving the back. Savings occur at slower speeds than 15 and 20, respectively, but those are easier numbers to remember. I will use those thresholds to dictate my body position.
12. An investment of 10% of bike cost should be spent toward a professional bike fit. For me, that gives me a budget of $1,200 x 10% = $120. I'm pretty sure a professional fit costs $175 or more, so maybe getting one will be an extravagance. I plan to do it anyway.
13. The position of the rider on a bike is 57% more important than the bike model (in terms of drag savings), so by improving my riding position I am pretty much getting a bike that is much faster, without actually having to buy a new bike. A fancy helmet represents only 25% of an improved bike position. Likewise, wheels reduce drag by only 25% of an improved ride position.
14. If I ever do buy a fancy helmet, research shows that the ones with shorter tails and steeper taper angles are better than the super pointy alien heads I like to make fun of. Air ventilation holes make no difference in terms of drag, so the more the better.
15. If I ever do buy fancy wheels, deeper rims is not always an advantage. Headwinds favor shallow rims, but cross winds favor deeper rims. The author did some calculations and determined that headwinds are more likely to be encountered than those that hit the bike from a cross angle, so my shallow rims are just fine. (what is my rim measurement, anyway?) compare to p. 99...Ok, and what about the increasing popularity of wider tires? That actually makes sense, given that a wider wheel slides through the air better than a narrow wheel with a tire that bulges out from the wheel on both sides. All in all, the best disc wheels will save 20 watts of effort, which saves about 2 minutes for every 25 miles of distance. See, 8 minutes is just not worth it on an IM race.
16. Tire choice makes an easy difference in drag reduction. The text is a equivocal on the significance of it, though. In one place, the author says that wheels reduce drag by a fraction of a unit, while tires reduce drag by a fraction of a fraction of a unit. This seems to indicate that tires don't matter. But later, the author shows that good tires can shave a minute off a 25-mile race, which is certainly small, but measurable nevertheless. It's easy and inexpensive to buy fast tires, so I will make sure I upgrade each time I race. (I still have my race tires from last time, and those may still be good)
17. Tire pressure of 110 psi is ideal for minimal rolling resistance. I already inflate to that pressure.
18. Clean the chain often. The author says to degrease it each time, and then lubricate with any oil--it doesn't matter what kind.
19. The race number stuck to your bike creates drag and it will be minimized by having it positioned stiffly to your seat post. I already do this with zip-ties.
20. Run efficiency is increased as we reduce the vertical displacement of each stride. That is, less bouncing up and down as I run. I think I am pretty good in this area already. I also want to maximize the distance covered per step and reduce the time spent in contact with the ground, says the author. However, he proposes a solution to all three of these things by saying: "shorten stride and increase cadence to 180-190 steps per minute." But ok.
21. As runners fatigue, their cadence drops and they spend more time on the ground per step. Both of these act as positive feedback on energy requirements so that fatigue then generates more fatigue and performance plummets. This promotes the idea that pacing is very important throughout a race so that I never get fatigued.
22. The most efficient runners minimize vertical displacement to the point where their feet only come 7.5 cm from the ground. I'm not saying I'm an efficient runner, but my impression is that I don't have a lot of vertical displacement.
23. Body weight is an important factor in running in the area of heat dissipation. Heavier runners don't dissipate heat as well, so they have poorer endurance. This is the reason why there are athenas and Clydesdale categories. Anyway, this is also another reason to shed pounds if I want to be the best triathlete I can be.
24. There is a fair amount of discussion of running shoes in this book, with the conclusion that scientific studies have not found any performance differences between cheap shoes and expensive shoes, nor between brands or sole designs. The author says to choose a comfortable inexpensive pair and replace the shoes often, soon after 300 miles. As a rule of thumb, therefore, I will replace my running shoes after 350 miles. Shoes degrade at this point, and studies show that the runner's foot and body start to alter running form to adjust to the change in cushioning, and "not in a good way." Indeed, even if a degraded shoe did not have a negative impact on foot architecture, the studies show that runners in worn shoes spend more time on the ground per step (see #21 above).
25. Running on a treadmill: Set the treadmill at at least 1% incline to better mimic the workout you get when running outdoors.
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