Tuesday, October 23, 2012

"Food and Macronutrient Intake of Elite Kenyan Distance Runners"

Not what I'm going to eat, but interesting:
"...Athletes carried out most of their training collectively as 1 group 2 times a day, typically before breakfast and dinner. The morning run (06:00) comprised a 6 to 9 mile run carried out at either moderate or fast running pace (e.g., 11 to 15 mph) depending on athletic specialization and instructions received from the coach/manager...."

"...Total fluid intake was modest and mainly in the form of water (1113 ± 269 mL; 0.34 ± 0.16 mL/kcal) and tea (1243 ± 348 mL). No water was ingested before or during the early morning run, although only a modest amount of water was ingested after training and not by all athletes. Similarly, only a small amount of water was ingested after the afternoon run by a small number of the athletes. No water was ingested during the run...."

"...Endurance athletes are advised to strive to maintain fluid balance before, during, and after exercise to avoid a detriment in performance as a result of progressive dehydration (2). In the present study, given the greater need for fluids as the Kenyan runners lived and trained in a warm, high-altitude environment, their fluid intake was fairly modest and comprised of water (1113 ± 269 mL; 0.34 ± 0.16 mL/kcal) and tea (1243 ± 348 mL). No fluids were ingested before or during training, although only a modest amount of water was ingested after training and not by all athletes. The previous two dietary studies in Kenyan runners (14, 6) made no particular reference to fluid intake, especially in relation to exercise training, and therefore it can be assumed that no specific strategies were adopted as in the present study. Although the drinking habits of these Kenyan runners is somewhat contrary to current dietary recommendations (2), it has recently been argued that some degree of dehydration could benefit marathon runners by increasing the pressure gradient across their capillary beds, increasing capillary flow rates, and decreasing intercapillary distances (9). It is common practice among elite Kenyan distance runners to consume considerably less fluid than is recommended. The overall significance of this has yet to be experimentally determined...."

"...The food and macronutrient content of elite Kenyan runners fulfilled most of the recommendations for endurance athletes for CHO, fat, and protein intake, but not for energy (i.e., negative energy balance) and fluid intake (2).... If anything, there would appear to be room for considerable “improvements” in the nutritional practices of elite Kenyan runners, with particular reference to energy balance and fluid ingestion, assuming current recommendations would indeed be advantageous and not detrimental to the running performances of elite Kenyan runners...."

"...As the Kenyan runners in the present study appeared to be in negative energy balance, maintaining the recommended protein intake would be vital for the health of the athletes. Negative energy balance can result in loss of muscle mass and increased risk of fatigue, injury, and illness (2). It is tempting, therefore, to ascribe the relatively fast “turnover” of elite Kenyan distance runners to this particular feature of the Kenyan diet (i.e., negative/borderline energy balance). Individual Kenyan runners tend to do well for a short time but “drop out” of the world running circuit or are unable to reproduce earlier running performances (personal communication with Brother Colm O’Connell, head coach of St. Patrick’s High School, Iten, Kenya)...."

"...The fact that the athletes in the present study lost weight lends more credibility to the accuracy of food intake being lower than energy needs; it appears less likely that the athletes underreported food intake...."

This: "...assuming current recommendations would indeed be advantageous and not detrimental to the running performances of elite Kenyan runners..." is a big assumption. I'd go with detrimental...

I also find the fact that they train in a maximally-fasted state very interesting, as I'm sure it helps them overcome the high-carb diet they're eating. Their bodies must rely on both stored fat and carbs for fuel.

I wonder what their Respiratory Quotient is when resting and exercising?

Friday, October 19, 2012

"Do You Know Your Footstrike?"

Great post:
"...The results? Among the "traditional" group, 20 of 22 claimed to be rearfoot strikers; in fact, they were all rearfoot strikers. Among the minimalist group, all 35 of the "minimalist" group said they were forefoot strikers; in fact, 12 of them were rearfoot strikers...."
Turns out this matters, as a lot of the minimalist heel-strikers were beating up their heels. See the graph at the link.
"...So in this group, minimalist forefoot strikers had smaller vertical loading rates than the traditional group, but minimalist rearfoot strikers had larger vertical loading rates...."
What this tells you is that it's not enough to buy a pair of minimalist shoes. A lot of minimalist shoes still have enough cushion underfoot to allow you to heel strike, even if you're an experience barefoot-style runner.

I bought a pair of the New Balance Minimus Trail Zero (MT00) when they first came out. Took them out for a spin, and noticed a noise: Thwip, thwip, thwip, thwip... I was heel-striking! They had just enough cushion under the heel to fool my feet!

Now that's after running exclusively in minimalist shoes and barefoot for 3+ years. I examine the wear patterns on my shoes, so I know what I'm doing, and I listen closely to my feet landing. But your body just naturally falls into a heel-strike if there's enough cushion to allow it. And, to answer Alex's question:
"So... who here has objective evidence of what their footstrike is? :)"
I do. If you really want to fix your form, you need to do at least some barefoot running.

Friday, October 12, 2012

Barefoot Running Club

Barefoot Running Club. Video at the link (couldn't figure out how to embed it). F-bombs abound.

Wednesday, October 10, 2012

"Mortality And Longevity Of Elite Athletes"

Mark Sisson posted "Why You Shouldn’t Burn More Than 4,000 Calories a Week Through Exercise" today, an extension of his Chronic Cardio concept. He states:
"Another study examined weekly caloric expenditure via aerobic exercise in a group of former athletes and non-athletes and plotted it against mortality, cardiovascular disease, and hypertension. Death rate was highest in groups 1 and 2, the ones with the least amount of caloric expenditure, but group 6 (along with 1), which expended 2,500+ calories per week, had the highest rates of heart disease and high blood pressure. Those who exercised moderately lived the longest and were healthiest."
Those were college athletes. While I'm open to the notion that some level of exercise is "too much", I don't find that particular study too compelling.

What happens to elite athletes, then? They must be dropping like flies, right?
"The health benefits of leisure-time physical activity are well known, however the effects of engaging in competitive sports on health are uncertain. This literature review examines mortality and longevity of elite athletes and attempts to understand the association between long-term vigorous exercise training and survival rates. Fourteen articles of epidemiological studies were identified and classified by type of sport. Life expectancy, standardised mortality ratio, standardised proportionate mortality ratio, mortality rate, and mortality odds ratio for all causes of death were used to analyse mortality and longevity of elite athletes. It appears that elite endurance (aerobic) athletes and mixed-sports (aerobic and anaerobic) athletes survive longer than the general population, as indicated by lower mortality and higher longevity. Lower cardiovascular disease mortality is likely the primary reason for their better survival rates. On the other hand, there are inconsistent results among studies of power (anaerobic) athletes. When elite athletes engaging in various sports are analysed together, their mortality is lower than that of the general population. In conclusion, long-term vigorous exercise training is associated with increased survival rates of specific groups of athletes."
Guess not...

Thanks to JohnK.

Thursday, October 4, 2012

Eating Meat For 1.5 Million Years

Scientists find oldest evidence of regular meat consumption by early humans:
"...Musiba said the evidence showed that the juvenile's diet was deficient in vitamin B12 and B9. Meat seems to have been cut off during the weaning process.

"'He was not getting the proper nutrients and probably died of malnutrition,' he said...."
Maybe the kid's parents were vegans.

Wednesday, October 3, 2012

Follow-up to "How To Stop Doctors From Killing Us"

"Extremely Disappointing Facts About Doctors":
"The gist of Unaccountable: What Hospitals Won’t Tell You — and How Transparency Can Revolutionize Health Care (copy sent me by publisher) by Mart Makary, a med school professor at Johns Hopkins, is that doctors have failed to regulate themselves. Nobody else regulates them, so they are unaccountable. In many ways, Makary shows, bad behavior (e.g., unnecessary treatment, understating the risks of treatment) is common. Hospitals hide how bad things are. Makary mostly discusses surgeons — he’s a surgeon — but gives plenty of reasons to think other specialties are no better....

"...Supposedly state medical boards oversee doctors. Makary devotes part of a chapter to describing how they don’t. He asked state medical boards why they don’t search a national database before issuing a medical license. “My favorite excuse was that they could not afford the four-dollar-per-doctor fee.”...
Read the whole thing. And I may have to go buy this book...

Original post.