Saturday, December 1, 2012

What's Your To-Do List Today?

I came across this in one of my little inspirational books today while cleaning up my desk..

The (REAL) To-Do List
  • Sing
  • Smile at strangers
  • Keep learning
  • Notice kindness
  • Eat ice cream
  • Hope
  • Count your blessings
  • Laugh
  • Love
  • Love some more

Tuesday, November 6, 2012

Running in the Dark


Now that Daylight Savings Time has ended for the year, a lot of you who run after work will be running in the dark, at a time when there are lots of cars out there on the roads.  If you are running on the road, make sure you are facing traffic, so you can see the cars coming at you.  Also, help drivers see you by wearing bright-colored and reflective clothing--things that illuminate when light hits them.


You might also get a clip-on red light that flashes and that you just clip onto your clothing somewhere.  If the roads are not well lit and you are afraid you might trip or run into something, you might think about getting yourself a headlamp.

Tuesday, October 9, 2012

Course Record for Chicago Marathon, First-time Marathon Wins at Lakefront

Ethiopia's Tsegaye Kebede broke the course record in Sunday's Chicago Marathon with a time of 2:04:38.  Read The Science of Sport blogger Ross Tucker's indepth analysis of the entire marathon here.

Up in Milwaukee, area local Paul Zdroik won his first marathon in the time of 2:27:09, and on the women's side, Jacqui Giuliano did the same, with a winning time of 2:55:07.  Tom Held provides an excellent report on the Lakefront Marathon here.

I roamed around enjoying the marathon atmosphere down at the last couple miles and finish of Lakefront, taking lots of photos:







Saturday, October 6, 2012

Marathons Tomorrow - Chicago and Milwaukee's Lakefront

Two great marathons tomorrow morning--the prestigious Chicago Marathon and Milwaukee's Lakefront Marathon.


The Chicago Marathon was first run 35 years ago and was called the Mayor Daley Marathon.  From about 4,200 runners that year, the marathon has grown to approximately 45,000 participants in this year's event, with some 1.7 million spectators expected to watch along the streets of downtown Chicago.

Elite athletes to watch are:
  • On the women's side, Liliya Shobukhova from Russia, winner of the last three Chicago Marathons,
  • Men's Boston Marathon champ, Kenyan Wesley Korir, and
  • Tsegaye Kebede from Ethiopia


Milwaukee's Lakefront Marathon, which I ran back in 2003, is a really nice little marathon.  It start north of the city in Grafton at the local high school and eventually runs down the Lake Michigan lakefront ending up at Veteran's Park right on the lake.  Interesting news items from Lakefront's website can be found here

It will be a little chilly for both marathons tomorrow, high temp forecast for Chicago is 54 degrees while Milwaukee only 51 degrees.

Friday, September 21, 2012

Using Caffeine as an Ergogenic Aid

In previous posts I have talked about how to optimize your training by:  
  • making sure you take enough recovery time from your hard workouts and long runs,
  • developing good nutritional practices both pre- and post-workout, 
  • getting the proper amount of sleep for your body, and 
  • managing the other stresses in your life.
You can also use certain ergogenic aids to your advantage in training and racing.  And, no, I am not suggesting you do anything illegal.  Ergogenic aids include anything you use externally to enhance performance, and include nutritional, physical, psychological, physiological, and pharmacological aids.  Examples include:
  • Nutritional - Proper pre- and post-workout nutritional timing
  • Physical - Lighter weight running shoes and lighter more sweat-wicking clothing
  • Psychological - The use of visualization and mantras 
  • Physiological - Blood doping (NOT recommended!)
  • Pharmacological -Anabolic steroids (NOT recommended!), Human Growth Hormone (NOT recommended!), amphetamines (NOT recommended!), and caffeine
Here I am going to talk about the use of caffeine as an ergogenic aid.

Studies on caffeine used as an ergogenic aid over the past 20 years have shown positive benefits for endurance exercise in both time trials and time to exhaustion.  Though fewer studies have been done with caffeine and high intensity exercise, some recent research has shown positive effects on activities lasting one to seven minutes resulting in fatigue, i.e. cycling, treadmill sprinting, rowing.

Mechanism of Action

Caffeine is a drug, it is a stimulant, and used to be on the banned list of the IOC (International Olympic Committee).  It was removed in 2004, likely because the amount needed as an ergogenic aid is 5/6mg/kg body weight, which produces urine values of caffeine that are less than what the IOC limits were.  Caffeine stimulates the central nervous system, and the effect on the cerebral cortex enables us to think clearer, concentrate better, and perceive exercise as easier (lowering Rate of Perceived Effort - RPE), thus allowing us to feel less fatigue.

In endurance events, caffeine ingestions releases fatty acids from adipose stores to be used by the working muscles sooner than normally would happen.  This delays fatigue by sparing limited amounts of muscle glycogen.  During intense exercise, caffeine promotes release of calcium ions in the muscles to enhance muscle contractility.

Dose and Timing

Research shows that positive benefits occur when the dose is about 5-6 mg/kg body weight, but no further advantage at doses over 6 mg/kg body weight.  There is some evidence of benefit at 2-4 mg/kg body weight.  Studies also show that peak concentration is seen in the blood at 60 minutes after ingestion of caffeine, so you should take your caffeine about an hour before performance.

Form Matters

Many of us take our caffeine in the form of coffee (yes please!), but research has shown that, for some unknown reason, caffeinated coffee is not nearly as effective as pure caffeine in producing the positive ergogenic results.  BUT, the energy drink Red Bull DOES produce the same results as pure caffeine in capsule form.


Takeaway - Caffeine may be used for better performance in both endurance and high intensity exercise, taken in either capsule form or in the energy drink Red Bull, and ingested about an hour before your exercise activity.

Wednesday, September 5, 2012

Biking in Wisconsin

Whew!  Pretty much on vacay since the first of August--no time to blog!  L.A. the first week, back to SoFL with daughter and grandson, back to WI and BIKING AND CAMPING for two weeks!  Then back to SoFL for a Labor Day weekend up in Stuart to celebrate my mom's 80th birthday with all the kids and grandkids.  Daughter and grandson go back to L.A. on the weekend, and I will be back in WI then too. 

The weather in WI was simply gorgeous throughout the month of August--80's and sunny nearly every day.  Wisconsin has lots of rails-to-trails, as most states do.  The Oak Leaf Trail runs right past our condo, so we have been running and riding bikes on that for a long time.  But we did not know about another trail, the Ozaukee County Interurban Trail, which goes through Ozaukee County just north of Milwaukee County.
What is very cool is that the Oak Leaf Trail connects with the Interurban Trail, so that I can ride from downtown Milwaukee up to Grafton, where John's office is, mostly on bike trail.  Which means--mostly no motorized traffic, biking through trees and parks and little towns.  I have been doing this little trek nearly every day, about 24 miles one way.  THEN, after work, John and I get on the bikes and do another 20-25 miles or so on the Interurban Trail heading north of Grafton.

Oak Leaf Trail
Brown Deer Park
Ozaukee Interurban Trail - Mequon
On the trail
On the trail
Cedarburg
Grafton
We heard about a trail over by LaCrosse on the east side of the state, the Elroy-Sparta Trail, a rails-to-trail going from Elroy to Sparta and decided we needed to check that out.  So on the Friday afternoon a couple weeks ago, we loaded up the truck with our camping and biking gear (plus the dog--we bought a bike trailer to carry her along with us!) and made our way over to a campground in Wonewoc, about 20 miles south of Elroy, the start of the Elroy-Sparta Trail.  Two days and two nights of camping and biking!

Saturday was 82 degrees and sunny--perfect biking!  We started in Elroy and biked about 20 miles up, going through two of the three tunnels on the trail.  It's quite hilly in that part of the state and the railroadbuilt tunnels (in 1873!) through these hills for the trains to go through.  The first two are about a quarter mile long and the third is three quarters of a mile long. 

Some pics on the Elroy-Sparta Trail:

Getting ready for the ride

Elroy-Sparta Trail

Joy & John 1st Tunnel

Our bikes

Coming out of a tunnel

Our campfire

Sunday, August 19, 2012

What's a Good Warm-up Before Intense Speedwork?

Before beginning a speedwork session, it is imperative that you prepare your body with a good warm-up.  Easy jogging followed by dynamic stretching will help warm and loosen up your muscles.  It has been shown that while elite runners have normal joint flexibility, they have more dynamic flexibility when running.

Start with easy jogging anywhere from 1 1/2 to 3 miles to get you moving more freely.  You can then do some dynamic stretches, which are movements similar to (but more exaggerated than) the way you will move during your more intense running.  These movements will help your agonist muscles (the ones doing the work) perform optimally by  allowing your antagonist muscles (the muscles opposing the working muscles) to relax. 

Some dynamic stretches you can do:

Lunge Walk - Take exaggerated steps forward with each foot, stepping forward as far as you can in a lunge and letting your knee come close to the ground.  Repeat 10-12 times.

Lunge Walk
Lateral Lunges - Standing, take an exaggerated step with one foot to the side, lowering yourself into a squat position. Stand back up immediately and lunge to the other side.  Do 5-6 times each side.

Lateral Lunge
Tilt Walk - Start walking and as one foot comes down lean forward and balance on that leg (with knee slightly bent) and lift other leg straight back so that your body is parallel to the ground. Come back up swinging back leg through to step forward on that foot and repeat action.  Do this for 30 seconds or so.

Tilt Walk
Zombies - Start walking and extend both arms straight out in front of you as you kick one leg up toward your hands as high as you can and then the other leg.  Do not bend forward; keep your back and head aligned vertically.  Do for 30 seconds or so.

Zombies
Leg Swings - Find a wall or tree to lightly hold onto for balance.  Standing on one foot, swing your other leg back and forth as high as you can in a controlled manner.  Do 10-12 leg swings on each leg.

Leg Swings
Lateral Leg Swings - Facing the wall or tree, both arms extended forward lean lightly toward it to hold yourself, swing one leg from side to side passing in front of your body, going as high as you can in a controlled manner.  Do 10-12 leg swings each leg.

Lateral Leg Swings
Trunk Rotations - While standing, lift both arms straight out to your sides and twist your torso to the right then to the left as far as you can in a controlled manner but without stopping.  Do 10-12 times.

Trunk Rotations
When you have completed your dynamic stretches, begin running again easing into 5 or 6 20 - 40 second strides before beginning your actual speedwork session.

Intense running brings your body systems close to their peak performance rate so it's important to gradually return them to near normal with a proper cool-down.  As you did for your warm-up, 1 1/2 - 3 miles of easy jogging will accomplish this and you can continue the recovery process by following up with some gently stretching.

Saturday, August 11, 2012

Ashton Eaton - World's Greatest Athlete

U.S. Olympian Ashton Eaton won the gold in the Decathlon yesterday.  Click here to watch a nice video from NBC.  And from SB Nation's Dan Rubenstein:


Monday, August 6, 2012

The Olympics! So Much Fun!

I am having so much fun watching the Olympics!  I love it, I love it all--the swimming, the diving, the gymnastics, track and field, even the table tennis and beach volleyball!  I watched the women's marathon Sunday morning with my two little grandsons, Jack and Michael. They spent the night with Grandma Joy so their parents could join in their neighborhood fun of "beer Olympics" on Saturday night. I was happy to have them--love my boys!

Each of these athletes' dedication to their particular sport is so inspiring. And listening to the back stories of some of them, how they practiced what they do for hours and hours and hours and years and years...    yes, they all have talent, but it takes more, a lot lot more, than just talent to be a champion.

I believe we all have that in us, the ability to develop and be a champion in whatever it is we like to do, whether it's sports or music or cooking or our job or whatever.  A little willingness..   a little willingness..  to get out of bed at 5 in the morning to get your run in, skipping that party (or going home early) because you're meeting your running buddies in the morning for your long run, doing one more interval on the track because you're feeling so good, and you know the training is working...

Training, practicing, resting, recovering, rejoicing in victories large and small. Not stopping when we fall down or make a mistake, but picking ourselves up, evaluating what went wrong, maybe get some advice..   and going back out there.  And starting again. 

Because it's what we do. And in the end, it's all so worth it. 

Thursday, August 2, 2012

Video: The Olympic Body

Film by Kate Peters, beautiful photography and narrative...

Monday, July 30, 2012

Another Training Component - Sleep

An integral piece of the overall training picture is getting enough sleep.  A sleepless night here and there is nothing to worry about, but if you consistently do not get the sleep you need and are training hard, your recovery from training will suffer.  Circulating cortisol and C-reactive protein (a biomarker of inflammation) levels in the body increase dramatically in even short-term sleep deprivation.

Everyone's sleep requirements are different, so how do you know how much sleep you need?  You should sleep until you just naturally wake up, without an alarm clock or someone waking you.  That's how much sleep you need.

In addition to the recovery benefits, research shows that adequate sleep improves motor skill performance (e.g. running) in adults.  Takeaway:  Make sure you sleep well most nights, and especially after a hard workout.

Thursday, July 26, 2012

Is Massage a Part of Your Training?


Though there is no scientific evidence that deep-tissue massage promotes recovery or prevents injury, it sure feels good, and there IS evidence that it can allow more blood flow to massaged areas.  Getting a weekly massage may not be in your budget, but if you are training hard, I believe that getting at least an occasional deep-tissue massage given by a trained sports massage therapist is well worth the money.

Common trouble areas for runners are quads and hamstrings, calves, deep hip (including external rotators), glutes, and the IT band.

You can do some self-massage as well, using various massage tools that are on the market.  One of the best ways for runners to massage themselves is by using a foam roller, which is a firm foam 6"-diameter cylinder of varying densities and lengths.  You use your own body weight to apply pressure to trouble areas, rolling back and forth over the area for about 60 seconds at a time, and avoiding bony areas.  Do some gentle stretching afterwards.  For injured areas, do this 2-3 times a day; for prevention, 2-3 times a week.

You can get foam rollers at Amazon.com:

 

Monday, July 23, 2012

Dehydration Myths Continued...



I posted today to my Facebook page this article published in the British Medical Journal (BMJ).  You MUST read it: 
"The truth about sports drinks"

If you click on the "Read responses" tab, there are some good responses, including one from Dr Tim Noakes.

Saturday, July 21, 2012

Post-Run Nutrition - Recovery Drinks

Continuing my last post about post-run nutrition...   some years ago there was a recovery product available by the name of JogMate.  It contained whey protein and casein both, plus carbs, and came in a tube..  like a small tube of toothpaste, which was very convenient to take along with you to wherever your workout or race happened to be.  Jane and I would make sure we had one after all our long runs, hard workouts, and races (if we remembered); it did seem to make our legs feel more springy and less heavy in the next couple days than before we started using it.  At the time, there were no studies on any recovery products, and we didn't know anyone else besides us who used JogMate.



Research began to come out in 2006 that a glass of low-fat or fat-free chocolate milk provided just the right ratio of carbs to protein (4:1) that, if ingested within 30 minutes of your workout, was ideal for muscle recovery and glycogen replenishing, better than ingesting carbs alone.  You can read a couple articles about it here and here.

Today, there are numerous products out there that have been formulated to aid in recovery in response to the research--Accelerade, Amino Vital, Endurox R-4, Gold Medal Aminos, and PowerBar Performance Recovery to name a few.  Whether you choose one of these or plain old chocolate milk, you'll recover better if you take something in with a 4:1 ratio carbs to protein within 30 minutes of your workout.

Thursday, July 19, 2012

Diet and Nutrition

I don't get into all the debate about what the "best" diet is.  Everyone is different; different things work for different people because our bodies are all unique.  And they can change.  Take me, for example.  Three to four years ago I began to suspect that I might have a gluten intolerance.  That means my body has adverse reactions to gluten, which is a protein in certain grains (wheat, barley, rye).  My whole life I have eaten bread, pasta, and pretty much anything and everything I ever wanted without any problems.  But now, ingesting just the tiniest bit of gluten sets off a whole host of symptoms, beginning with neurological symptoms of tingling, numbness, heaviness on the left side of my body, severe fatigue and nausea, severe migraine headache, and then gastrointestinal symptoms of bloating and diarrhea.   This goes on for more than a week.  So I have gotten very, very good at keeping gluten out of my diet.  It's been difficult, because it seems to be in EVERYTHING, and cross-contamination is always a possibility.



One of my grandsons has a milk allergy and a nut allergy.  He could have such a bad reaction that he could actually die from ingesting walnuts.  There are kids with a peanut allergy who react the same.  My daughter-in-law is lactose intolerant; dairy gives her severe gastrointestinal problems.




Whether you eat a vegetarian or vegan diet, a Paleo or low-carb diet, I don't care.  You need to find out what works for you, what makes you feel good, what gives you the right amount of energy...   and let others find their own way as well.  I will say that eating whole, real, quality food is best--fresh fruits and vegetables, quality proteins and fats, whole grains.  If you can do that most of the time, you're good to go.  








All that being said, as a long distance runner, you need to ingest a certain amount of fluid, carbs, and protein along with foods that provide antioxidants, to help your body prepare for your run (pre-run) and to help your body recover from your run (post-run). 

Pre-Run Nutrition

I like to tell my runners to eat their carbs around their running.  If you are going out for a long run early in the morning, eat a high-carb dinner the night before.  You also need to drink water, as fluid ingestion is required along with the carbs for storage in the body.  You may or may not want to eat something before you run in the morning, and you will need to experiment with what works for you.  But if you do, it should be light and not more than a few hundred calories.

Post-Run Nutrition

Ingesting fluid, carbs, and a little protein within 30 minutes of finishing has shown to be most important in recovery from and adaptation to the stress of your run.  That is the time when your muscles are most receptive to glycogen resynthesis and muscle repair.  Though receptivity will gradually decline after that first 30 minutes, it does remain high for about 90 minutes, so you should then eat a regular meal that includes carbs, protein, foods with abundant antioxidants, and fluid within a couple hours of your run.

A word about ingesting calories during your run--contrary to current practices, recent research has shown that taking in a lot of (or any) calories during your long run is unnecessary.  In fact, if you do normally use some gel or sports drink during your long run, it's a good idea to go without any calories and just drink water to thirst for at least a few of your long runs.  This will help your body adapt better to storing glycogen, so that in your future long runs (and races) your body will be more efficient in burning glycogen, relying more on fat.

Experiment with different ways and decide what works best for you.

Saturday, July 14, 2012

London Olympics 2012 Countdown

The Olympics begin next week, July 27th.  Here's a fun video with Dan Rubenstein to begin the countdown:



Thursday, July 12, 2012

Watching Elites Run

Last month I posted about watching elite runners run, and that I would be watching the U.S. Olympic Track & Field Trials to do just that.  I found some great videos of both men and women's 1500m and 5000m finals shot by Jeff Moreno, PT, DPT, OCS, at Precision Physical Therapy & Fitness, and posted on his blog here.  The runners pass by as Moreno stands with his camera stationary; it's just a few seconds, but in slow motion so you can really observe each runner's form. 

I will post his videos of men and women's 5000m finals:



Wednesday, July 11, 2012

Jeff Bezos - The Difference Between Gifts and Choices

I am a huge fan of Amazon.com...   the amazing brainchild of Jeff Bezos.  I found this video of Bezos giving the Baccalaureate address to Princeton University's Class of 2010.  He asks the graduates to think about what their talents are and how they will use them in the world, but the deeper question is what choices will they make..       Watch:

Monday, July 9, 2012

Drinking Water on Your Run

Continuing with the previous post about hydration and running...  I want to speak a little about my experience.  Living and running in South Florida is a bit different than anywhere else (except places like, say, Texas).  The summers are hot, but it's the humidity that gets you if you are not acclimated to it.  The sun is very intense, even in the winter months.  You have to drink somewhat more here but it's still "drink to thirst."

When I first began running (here in SoFL) I did not drink anything before or during a run, which was fine because my runs were usually around 5 to 8 miles.  At that time I knew very little about running and I felt that drinking anything would make me feel bad, so I didn't.  Even when I started training for my first marathon, I did not drink anything for runs up to 12 miles.  Even in our SoFL hot and humid summer!  I only began drinking during runs when I started doing longer long runs, more than 12 miles.  I ran alone mostly and not on A1A where there are drinking fountains all along the path, so I would go out early before my run and stash water bottles (which I had put in the freezer the night before) along my running route.  I also did not use any sports drinks or gels for those first couple marathons.  And I had no problems.  I ran 3:56 for my first marathon (at age 39)--New York City 1993, which was the warmest NYC Marathon on record, up in the high 70's I believe; and 3:37 for my second--again NY the following year, 1994, and the second warmest with temps in the low 70's.  (No chip time then, by the way!)  I remember trying to drink some at each water stop, but missing several, as I wasn't ready for it when it came up and would be in the middle of the road or on the wrong side so I would just keep going.  I did just fine in both marathons.  Of course I had trained all summer in South Florida, so 75 degree temps with 50% humidity felt great!

Fast forward many, many marathons later, when I began doing ultras, I learned to carry water with me, as a lot of ultras at that time had long periods (many miles) between aid stations.  I started out with a single bottle in a pack around my waist, which I did not like at all (it bounced), then went to a Fuel Belt, with four little bottles evenly spaced around the belt, which I also didn't like.  I eventually started using a handheld, and got so attached to it that I now carry it on all my runs...  it has become a part of me.  It just works for me.  I like to be able to drink when I want to.  It's not that I drink a lot, it's just that it's there when I want it and I can take sips instead of having to take in as much as I can at the water stops.
Me in my huaraches with my handheld
 So, I am totally on board with Dr Noakes' "dehydration myth."  We need to trust our bodies, trust how we feel, rather than advertisements based on fear.  I believe that having access to water WHEN you want it is best, so that you don't need to force yourself to drink more than you want so that it will "last" till you get to the next water stop.  That's why I like carrying a bottle.  My favorite handheld is the Ultimate Direction Fastdraw 20-oz, but there are many to choose from.  Amazon.com has lots:

Sunday, July 8, 2012

Drink to Thirst - Tim Noakes' New Book

I recently bought Tim Noakes' new book Waterlogged.  I've been looking forward to it coming out since I listened to him on a podcast several months ago speaking about the book and his conclusions regarding what he calls the "dehydration myth."  Noakes explains in the book how essentially Gatorade and the rest of the sports drinks companies have sold the public on the idea that we all need to keep ourselves from becoming even slightly dehydrated, or we will suffer terrible consequences.  But according to all the research that he can find on the subject of dehydration (and he finds a ton), this is a just not true; in fact, quite the opposite is true.  Becoming OVERLY hydrated can cause serious problems.

I have only just started reading the book and was going to write about it after I finished it, but I came across an article in Running Times magazine that excerpts Chapter 2 of Noakes' book. You can read the article in Running Times here, but I think this is really important so I am posting the Chapter 2 excerpt from Running Times:

Drink to Thirst 

An Excerpt From Tim Noakes' New Book Waterlogged

EDITOR'S NOTE: Tim Noakes, author of Lore of Running, has a new book out that will surprise many readers and perhaps even offend some. In writing Waterlogged, Noakes pored over seemingly every bit of research ever conducted on hydration and performance and concluded that much of what we've been told on the topic is wrong. Noakes says we've been sold a "dehydration myth." In the following excerpt from Chapter 2 of Waterlogged, Noakes explains the physiology of dehydration and how research on the topic often contradicts conventional wisdom.


"Dehydration" is a physiological term indicating a reduction in the total-body water content. Once the reduction in body water causes the solute concentration, especially the sodium concentration (actually the osmolality), of the blood to rise, the brain detects the change and develops the symptom of thirst. This is a normal biological response that has evolved in all creatures to ensure that they maintain a constant body water content at least once each day, usually after the evening meal.

When fluid is lost from the body, either in sweat as a result of exercise or from the gastrointestinal tract in diseases like cholera or typhoid, the concentration of solutes, especially sodium in the blood, rises, causing the blood osmolality to increase. This rise stimulates receptors in a special part of the brain, the hypothalamus, which in turn interact with three other nuclei, which increase secretion of the hormone AVP/ADH (arginine vasopressin, also known as antidiuretic hormone), whose function is to increase water reabsorption by the kidney. In response to the action of AVP/ADH, the kidney reduces the amount of fluid secreted. As a result, urine flow into the bladder is reduced. Nucleus 5 also stimulates the cells in another part of the brain, the cingulate gyrus, which increases thirst. As a result, the desire to drink is increased and water (and sodium through the action of aldosterone) is reabsorbed by the kidneys. The result is that the blood osmolality returns to its homeostatically regulated value, switching off the desire to drink.

Thus the only symptom of dehydration is thirst. If, however, the thirst cannot be quenched because fluid is unavailable, as occurs in those stranded in the desert, then the body activates a series of emergency adaptations that prolong life for a period but ultimately cause death when all the major bodily organs fail, leading probably to cardiovascular collapse.

The remarkable achievement of the sports drink industry was that it convinced recent generations that these control mechanisms do not exist. Instead, we've been told, all athletes must drink to ensure that they do not lose any body weight during exercise. But there are no known receptors that regulate thirst by monitoring the extent of the body weight lost or gained. In addition, this myth also convinced exercisers that they could become dangerously dehydrated not just when lost in the desert for more than 48 hours but when running for a few minutes in, for example, a big-city marathon, during which they have unrestricted access to as much fluid as they might wish. I am unaware of any other human activity in which so much fluid is freely available as in a modern big-city marathon. How is it possible under these circumstances to become dehydrated except according to a definition that has no proper biological basis?

In response to the body's pure fluid loss, the usual human living in a Western society with easy access to fluid will develop the sensation of thirst and will usually drink fluid as a result. Receptors in the back of the mouth and the esophagus, but particularly in the stomach, then detect how much fluid has been ingested. Once the stomach is filled, the desire to drink is temporarily curtailed but resumes as the stomach empties, especially if food is eaten at the same time. Eventually enough fluid (and sodium) has been ingested to return the solute concentration of the extracellular fluid (ECF) back to the normal range. Since the ECF (and hence whole body) osmolality is then within the homeostatically regulated range, the symptom of thirst is switched off; as a result, most people will stop drinking.
SYMPTOMS OF INADEQUATE FLUID INGESTION

When athletes sweat during exercise, they lose both water and electrolytes, especially sodium, in varying amounts. Because sodium is the dominant solute lost in sweat, and since the sweat sodium concentration is always less than its concentration in the ECF, sweating will always cause a greater loss of water than solute from the ECF. As a result, in the absence of any fluid ingestion, sweating must cause the ECF solute concentration to rise. Ultimately this will change enough to stimulate thirst in everyone.

However, this response is highly individualized--some athletes will become thirsty at quite low levels of weight loss, whereas the thirst of others allows them to lose up to 12 percent of body weight during ultra-endurance exercise, as in the Ironman Triathlon, without developing any more severe symptoms of homeostatic failure. To understand the real symptoms that develop when people drink less than their thirst dictates, we need to look at those studies in which participants are forced to exercise for prolonged periods while they have access to less fluid than their thirst dictates. These people develop both an unquenched thirst and additional symptoms caused by a progressive biological failure due to a falling total-body water content. One of the original studies to define these symptoms was performed in the Nevada Desert during the early years of World War II.

The Nevada Desert study reported the sequence in which symptoms of unreplaced water losses, since conveniently termed "dehydration," developed. Of course, one can equally argue that some of these symptoms are due to an absence of drinking and the knowledge that drinking will be allowed only when the activity is completed. We now appreciate that the brain responds not just to biological stimuli but also to what it anticipates will happen in the future. Knowing that a demanding activity must be performed without fluid replacement will cause all symptoms to be experienced more intensively.

The head of the Nevada Desert study wrote, "The order of appearance of the signs and symptoms is particularly characteristic. Thirst is noticeable very early, but does not increase much in intensity as the water deficit continues to increase. Vague discomfort, not experienced by controls who drank water, gradually becomes defined in the flushing of the skin, heat oppression, weariness, sleepiness, impatience, anorexia and dizziness. At about the time that the walking pace can no longer be maintained, dyspnea, tingling and cyanosis, as well as a suggestion of tetany, appear. Still later, a man cannot stand alone, either because of impaired coordination or fainting." The Nevada researchers also recognized that the inability to stand was due to the development of a low blood pressure, postural hypotension: "The inability to continue muscular work (exhaustion) seems to be a consequence of circulatory inadequacy. Temporarily, the movements themselves help in some degree to improve the return of blood to the heart. When the movements stop, failure is suddenly imminent; some persons faint at this point. Lying down promptly relieves the circulation and the symptoms."

Another Nevada Desert researcher described his experiences: "Aside from thirst, the symptoms of dehydration were in large part indications of impending collapse. A vague, generalized discomfort and a feeling of restlessness followed closely the stage of 'mouth thirst.' There was a great desire to sit or lie down. Drowsiness was often noted. A feeling of heat oppression was a frequent complaint; it was often more serious than thirst. Muscular tiredness grew more acute progressively, although manual coordination was not measurably altered. Among the signs of approaching collapse, the most reliable were a rising pulse rate and a rising rectal temperature. Sometimes there was a noticeable dyspnea. Frequently, the subject was cyanotic and his face became flushed. In the exhausted state, tingling in hands, arms and feet occurred in some cases."

So described are the real symptoms that develop when people exercise in extremely hot conditions without any chance to replace their fluid losses appropriately. Of course this is not what happens in modern marathon races in which athletes exercise usually for relatively short periods of a few hours in much cooler conditions while they have access to unlimited amounts of fluid.
The extensive research of the Nevada Desert research group established a range of findings that subsequent research has not contradicted. Not all these findings have received equal exposure over the years. Those findings that dehydration may not be quite as dangerous as the dehydration myth proposes have not been as widely propagated as those supporting the value of fluid ingestion during exercise. The principal findings were as follows:

1. Even when given free access to adequate fluids, people drank less than they lost in sweat or urine. Hence they developed "voluntary dehydration," which was corrected only after exercise and when food was eaten, especially at the evening meal.

2. In the experiments in which groups of soldiers either drank freely or not at all during day-long marches in desert heat, a much greater percentage of those who did not drink during exercise were likely to terminate the exercise bout prematurely.

3. Subjects in the groups who did not drink during these marches usually stopped when they had lost 7 to 10 percent of their starting body weights. In this state they experienced postural hypotension (EAPH), but after they experienced the symptoms of fainting caused by EAPH, they recovered rapidly within minutes of lying down and ingesting fluid.

4. Dehydration reduced neither the sweat rate, nor the rate of urine production during exercise. However, the rectal temperature and heart rate rose as linear functions of the level of dehydration. The body temperature rose about 0.2 to 0.3 degrees C for each 1 percent level of dehydration.

5. There were no immediate health risks associated with the level of dehydration of 7 to 10 percent present at the termination of exercise in those who did not ingest any fluids during exercise. The authors considered that only at very high levels of dehydration (15 to 20 percent) was there a serious risk of organ failure.
These studies, which clearly established the value of fluid ingestion during exercise, had little impact on the athletic community. Instead, for at least the first two decades after the publication in 1947 of the book describing these studies, athletes continued to be advised not to drink at all during exercise. Only after the development of Gatorade and the publication of relevant studies was proper attention finally paid to the use of fluid ingestion during exercise.

Another set of U.S. Army studies occurred soon after American troops began to fight in jungle heat in Burma during World War II. It soon became apparent that on first exposure to conditions of high temperatures and suffocating humidity (caused by the transpiration of water from the leaves of the jungle vegetation), soldiers were essentially incapacitated but began to adapt within a few days. To study the special physiological challenges posed by jungle heat, a special research group was established at Fort Knox, Ky., where a "hot room" was built in which the environmental conditions present in either the desert or the jungle could be reproduced.

These studies showed that the major cause for incapacitation on first exposure to both desert and jungle heat was the development of EAPH, beginning the moment the exercise bout terminated. This disappeared within a few days of repeated heat exposures. An important contribution of these studies was to establish the condition of EAPH as a cause of post-exercise collapse and to show that this condition was not simply due to dehydration, as would become the industry-driven mantra after the 1980s.

These researchers were also interested in the psychological effects of exercising in the heat without fluid replacement. Thus they wrote the following: "An important change which the chart does not show was the actual condition of the men, their low morale and lack of vigor, their glassy eyes, their apathetic, torpid appearance, their 'don't-give-a-damn-for-anything' attitude, their uncoordinated stumbling, shuffling gait. Some were incapable of sustained purposeful action and were not fit for work. All they wanted to do was rest and drink." This shows that the symptoms of dehydration are largely of a psychological nature, the goal of which is to stop the athletes from continuing to exercise. It's a built-in mechanism to prevent bodily damage.

Scientists at the United States Army Research Institute of Environmental Medicine have conducted a study to evaluate the influence of unreplaced fluid losses on the development of various symptoms. The study used fluid restriction and exercise to produce four levels of loss of body weight (0 percent, 3 percent, 5 percent, and 7 percent) and showed that the intensity of sensations of thirst, tiredness, weakness, lightheadedness, weariness and dizziness increased linearly with increasing levels of weight loss. But thirst was the symptom that was felt with the greatest intensity.

The study is important for two reasons. First, it shows that thirst is the symptom that best indicates the presence of a fluid deficit caused by exercise and fluid restriction. This conflicts with the myth developed in the 1990s that thirst is an inadequate guide to the fluid needs of the body. Rather, in this study, a weight loss of 7 percent produced near-maximal thirst sensations.

Second, during competition, some athletes develop levels of weight loss in excess of 7 percent without developing the same intensity of symptoms experienced by the participants in this study. This shows the individuality of the thirst response. Athletes who lose substantial amounts of weight during exercise without becoming as thirsty either prevent a large increase in the solute content of their ECF (as a result of internal relocation of body sodium stores) or because their brains are less sensitive to any large changes in ECF solute concentrations.

These individuals are, in fact, dehydrated because they have lost total-body water; however, this water loss is easily replaced by drinking normally, often with a meal, after the race. It does not lead to myriad ill effects, as the sports drink industry would like us to believe. In fact, the best endurance athletes in the world are typically those who lose the most weight during exercise, who have the least thirst and who run the fastest when they are quite markedly dehydrated, perhaps because the weight loss is beneficial to performance, just as the avoidance of thirst must have been an advantage to early hominid persistence hunters.

More recent studies further confirm that the sensations of thirst are always sufficient to ensure proper hydration both before and during exercise. Participants who began exercise in a dehydrated state (-3.4 percent BW) drank 5.3 times as much fluid during 90 minutes of exercise than when they started exercise normally hydrated such that, provided they were able to drink during exercise, it made no difference whether subjects began exercise dehydrated or normally hydrated; by the end of exercise their core body temperatures, heart rates, blood osmolalities and thirst ratings were the same.
FLUID LOSS AND PERFORMANCE

If fluid loss leads to thirst, why do some of the best competitors finish endurance races in quite advanced states of fluid loss? Time and again, studies, even those by researchers expecting different outcomes, have shown that the runners who are the most dehydrated, as measured by percentage of body weight loss, run the fastest. Two examples that valdiate this conclusion are the results of the 2000 and 2001 South African Ironman triathlons and the 2004 New Zealand Ironman Triathlon.

The largest body weight loss in these studies was 12 percent in an athlete who finished the race in ~720 minutes. The five fastest finishers in the South African Ironman all finished in less than 9 hours and all lost 6 to 8 percent of their body weights during the race. Three years later, this relationship was confirmed in finishers in the 2004 New Zealand Ironman Triathlon.

Why would the fastest endurance performers exhibit the highest percentages of body weight loss during their winning performances? Perhaps clues exist in the phenomenon that has been termed voluntary dehydration. Exercising humans do not drink to maintain a constant body weight every moment of the day. Rather, we develop a water deficit termed voluntary dehydration by drinking less than the amount of weight (assumed to be due entirely to water loss) that we lose as sweat during exercise. Only at mealtimes do humans increase water intakes and so correct exactly the fluid loss developed in the hours between meals.

There are a number of probable explanations for this phenomenon. First, not all the weight lost during exercise is fluid that needs to be replaced immediately. For example, there is an inevitable loss of weight caused by the fuel, either fat or carbohydrate, that must be burned in order to provide the energy needed for the exercise. The analogy would be the fuel in a motor car that is burned as the car travels--the result is that, until it is again filled with fuel, the car loses weight in direct proportion to how far it travels.

An additional factor is not covered by this car analogy. It is that the carbohydrate that is burned during exercise may be stored in the muscle and liver in a complex that includes a substantial mass of bound water. It has been argued for some years that each gram of carbohydrate used during exercise releases up to 3 grams of water. This water acts as a fluid reserve that is restored only when the body's carbohydrate stores are again filled 12 to 36 hours after exercise. Because the body can store 500 grams of carbohydrate (with an associated 1,500 grams of water), this would explain why humans might lose at least 2,000 grams of weight during exercise without any real water loss. Indeed, studies of this problem have shown that exercising humans can lose at least 1,000 grams without a measureable change in their total-body water content.

Thus the term "voluntary dehydration" may not accurately describe what happens in athletes who lose less than 1 kg during exercise because they may not have lost any body water and hence are not dehydrated. But athletes who lose more than 3 kg during prolonged exercise probably do show a reduction in total-body water content and hence are likely to be voluntarily dehydrated to varying degrees. The explanation for this phenomenon is that already given--either they prevent a large change in ECF solute concentration in response to quite large changes in body water content or their brains are less sensitive to a normal increase in ECF osmolality (solute concentration). But either way, the fact that athletes with the greatest levels of weight loss are usually the fastest finishers in endurance events shows that the response of their brains to body water loss has been entirely appropriate, perhaps optimal.

There is no direct evidence that exercise performance is impaired in those who lose weight during exercise, provided they drink to the dictates of thirst and do not become thirsty. In fact, evidence that the best marathon runners have a remarkable capacity to resist high levels of fluid loss has been provided in countless races around the world.
Copyright © 2012 Running Times Magazine - All Rights Reserved.
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Thursday, July 5, 2012

No Time to Blog... Having Fun with My Grandson

I have been traveling with my 3-year-old grandson since last Friday, first to the "family farm" in Indiana where we rode the tractor, fed the horses, walked in the fields, and saw lots and lots of aunts and uncles and cousins. 

Then we came to Milwaukee, where we are now through Friday, and have been on the boat.  Yesterday was the zoo and a baseball game--Brewers vs Marlins.  They tied 6-6 and went an extra inning with the Marlins scoring the winning run.

I have been posting to my Joy Frantz Coaching Facebook page, which you can see here.

Looking out the back of the boat

Sunday, June 24, 2012

Ashton Eaton - Decathlon World Record at the Trials in Eugene!

Ashton Eaton, amazing young man!  Read ESPN Olympic Sports' story here.

My friend Dottie just told me her husband went to high school with his mom.  She sent me a couple photos..
Ashton Eaton

Ashton with his fiance and mom

The 1500m..


Ashton after..

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