If you're not into running, my annotations should suffice to sate your curiosity. If you're a runner, you'll enjoy the whole book. Happy trails.3 stars.
Here's the reason why you should always warm up before vigorous exercise. "Cooled muscles unload oxygen more slowly from the blood, reducing the capacity for high rates of power output." p20
How exactly does the oxygen move from the hemoglobin in your blood to the muscles cells that need it? "Myoglobin is within the muscle fibers (cells), and by oxygen there even more easily than hemoglobin binds oxygen in the blood, it removes oxygen from the blood and makes it available to teh cell's metabolic pathways." p66 As an aside, slow twitch muscle has lots of myoglobin, but fast twitch muscle doesn't. Myoglobin makes meat red or dark when cooked. White meat (especially in poultry) has very little myoglobin. Chickens use their breast muscle for brief flight attempts so they have fast twitch muscles there. Ducks on the other hand fly long distances, and their breast meat is quite dark.
"Distance runner's leg muscles contain predominantly - 79 to 95% - slow twitch muscles vs. 50% in the avg individual and about 25% for elite sprinters. " p67
"Bees regurgiate their stomach contents from the mouth and spread liquid all over themselves with their forefeet [to cool themselves down via evaporation - analogous to sweating]." p101 And you thought sweat was stinky and disgusting, imagine if on a hot day we had to vomit all over ourselves to keep our cool. Could it possibly get any grosser than that? But of course! Never underestimate biology. "Storks defecate runny feces down their legs. The blood in the bird's legs is cooled by the evaporation, which reduces overall body temperature by as much as 2 degress celsius." p102
"Geese fly over the summit of Mt. Everest (reaching altitudes over 30,000 feet!)... where the air is only 1/3 that at sea level." p113 Birds have lungs that are nothing like ours. It takes them two full breaths to move air completely in/out of their lungs, allowing them to get twice the exposure.
Pronghorn antelope can reach speeds of 61 mph and cover 7 miles in 10 minutes (p119). But the ultimate endurance athelete is actually the camel. Here are some fun facts on the dromedary ultra-marathoner par excellence:
Top speed is only 10 mph - compared to a racehorse of 35 mph, but a camel can cover 100 miles in 16 hours - a racehorse only goes 1.5 miles in 2.5 minutes. p135 "In a 1 day race between a horse and a camel over a 176 km course, the horse barely won. The next day the camel just kept on going like normal. The horse died." p135
"The advantage of carrying the fat on the back, rather than evenly distributed all over the body, is that it leaves the belly and other shaded areas less insulated and thus more available for heat loss from the body core... The fatty lump serves, like our head hair, as a heat shield from the sun in middle of the day, so that less water needs to be lost by sweating." p138 "A shorn camel lost 50% more water [from sweating] than a fully furred one." p141 So the hump doesn't actually store water, but it helps save water none the less.
"We're near death if we lose water equal to about 12% of our body weight, but camels can survive body water loss of 40%. After being dehydrated, a camel can ingest upto 25% of it body weight in one drinking bout... Camels can rehydrate even when drinking brackish or salty water that dehydrate us since we'd expend water to flush out the ingested salts. In contrast the camel's powerful kidneys can make urine twice as concentrated as sea water, allowing them to get rid of much waste using little water." p140
Dehydrated camels can allow their body temperature to fluctuate by nearly 12 degrees F (93 to 105) with little ill effect. If their skin temperature rises above 113F, they must sweat to prevent overheating."Our own body temperature dips 2-3 F below normal at night" p 141
Why would we evole bipedalism when it is less energetically efficient that quadripedalism? "Bipedal posture [vs. quadripedal posture] experienced 60% less direct solar radiation. In addition, in that posture the body is better situated to take advantage of breezes for convective cooling." p166Why would our bodies care so much about the overheating? "Takeovers [stealing a carcass from other scavengers or hunters] would have been difficult at night [for our ancestors], and it would been easiest in the middle of the day when the predator had retired into the shade, leaving carcasses untended or at least less vigorously defended." p167
What was the rush all about? Why couldn't we take our time in the mid-day sun to reach the carcasses? "Traveling fast and long would have been a great premium for getting to predator-killed carcasses before the competitors [think vultures, jackals] devoured it." p168
"By about 2 to 3 million years ago, the bipedal plains hominids already had a leg and foot structure almost identical to our own." p169 It is around this period that there is evidence of our ancestors transforming from scavengers to predators.
Sweating is a uniquely human characteristic. "We don't need a sweating response to outrun predators, because that requires relatively short, fast sprinting, where accumulating a heat load is, like a lactic acid load, acceptable. What we do need sweating for is to sustain running in the heat of the day - the time when most predators retire into the shade."p174
"On a continuous run of 60 miles on a moderate to cool day, an ultramarathoner may lose nearly 20 pounds of water by sweating alone." p174 That's about 9lbs for a marathon, or about 1 lb or 16 oz per 3 miles.
"Bushmen of southern Africa were well known for being able to run down swift prey, including wildebeests and zebra, provided they could hunt in the heat of the day. The Tarahumara of northern Mexico chase down deer till the animals are exhausted... The Paiutes and Navajo were reported to do the same with pronghorn antelopes. Australian Aborigines chase down kangaroos, but only by forcing them to reach lethal body temperatures." Distance running in the heat of the day is in our blood the world over!
What was a typical day like for our African ancestors? Perhaps today's bushmen can offer us a glimpse. "Often they travel 30 Km per day (19 miles), come home with nothing, and by next morning are off again... They carry no food or water with them, because that hinders their ability to travel. They might follow a wounded giraffe for five days." p180 Thank goodness we have Safeway.
Why boys love to play sports and girls love the athletes that do. "Could the origin of our dances, like our athletic games that provide worthless ribbons, medals, and trophies, be symbolic activities that show off our capacities [for being good hunters in the eyes of potential mates]?"
"For most animals continuously available food translates to never being fat because there is then no need for fat, but advantages to being thin... Fasting is a danger signal that says 'Food is getting scarce - stock up if you possibly can.' Thus I predict that when trying to lose fat, a very gradual decreased caloric intake will not allow the body to notice that it is fasting." p203 "Dieting can reduce metabolic rate by as much as 45%, making one weak, sluggish, and slow, while reducing weight only slightly." I have been doing exercising more and eating slightly less for 3 months now (March 2005 till May), and I've lost 15 lbs of fat and only fat since my strength with weights has stayed constant.
Hey fatso, blame it on your parents, grandparents and their parents. "Humans like bears and birds are obviously also capable of laying up fat stores, which suggests that our ancestors very likely experienced times when food was abundant, followed by times when food was scarce... Further, our ability to fatten at any time tells us tht those who survived to be our ancestors were capable of fattening when opportunity arose. " p204
How many guys have heard this question? 'Why does ice cream always go to my butt and thighs?' Well here's the answer you've been waiting to tell. "In human history, women were either pregnant or lactating virtually continuously... In a world of often limited resources, fatness was associated with fertility, and most likely considered sexy. In females, the distribution of fat might have evolved to accentuate its presence, so that it could be shown off." p204
"Lifting 1 oz of extra foot weight 1 inch higher than necessary [while running a marathon] would be quivalent to lifting a 390 lb weight a distance of 1 foot." p226 Thats why you should run with the lightest shoes, no socks, and why some runners prefer running barefoot.
"Suppose a 150 lb runner goes up-down only 3 inches with each step; then over the course of a marathon he will have lifted his 150 lb body mass a distance of about 1 mile." p227
"Some think that you are given a specifc number of heartbeats per lifetime, and they would not rather use up their quota by running [or exercising]. Running may increase your heart rate up to 120 to 140 beats per minute from a normal 60, after a few months of training, the resting heart rate for the other 23 hours of the day may greatly decrease. "p234 Let's say you run 1 hour a day at 120 beats/min, yielding 7200 beats for the workout, but this drops your rest rate to 45 beats per minute from 60. Total beats per day while exercising is 7,200 + 23 hours x 60 minutes x 45 beats or 69,300. If sedentary, you have 60 beats per minute x 60 minutes x 24 hours = 86,400. So if this theory is true, you would live 20% longer by exercising vigorously every day to lower your heart rate.
"Many animal studies, from mice to monkeys [and now people based upon the Okinawa study], show that reduction in caloric intake increases health and longetivity, then maybe the relevant variable is caloric deficit, and so exercise, by reducing caloric excess, should do the same as caloric reduction." p236 Can I have my cake and run with it too? I've always wondered that if the theory caloric reduction is based upon assumptions of oxidative exposure, why exercise doesn't accelerate aging and detoriration. Maybe it has nothing to do with oxidation (or the power of anti-oxidants to save you), but simply a slow down of overall metabolic processes because the body is in a perpetual state of perceived famine.
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