This past week week I had two goals - we dialed down the distances and times for a classic "cut back week" and to begin a mini taper for the upcoming Steelhead 70.3 on August 1st. I've been feeling a little tired and my job has been testing my time for quality training so my "long ride" was back to 90 minutes and "long run" at 90 minutes as well. I think I've re-charged a bit. I feel ready for the race and to move into the Ironman specific training distances in the next 6 - 8 weeks.
The only real challenge I see so far has been getting some good open water swims in this year. While I have been doing countless laps in the pool, I was hoping to get out in the lake a few times to practice with my wetsuit (which, I must say, I haven't worn since I finished the swim at Ironman Arizona last year). Living in Chicago, our only good option is the Ohio Street beach, which could be a great place since it has marked lanes and life guards for open water swimming. The downside is that it is basically open to all the run-off and trash from the city, so any rain turns it into an open sewer. And yes, Chicago has had a lot of rain this year. I see swimmers out there, but I'd rather not get sick from water. Besides, wet suits are not allowed at Kona, so what's the big deal, right? Only if it were so easy....
So any of you following my journey to Kona, please keep me honest and check back to make sure I am out in the open water. Until then, see you at the pool....
Thursday, July 23, 2009
The History of the Science of Hydration and Human Beings
Lets take a few minutes to explore the history of hydration and endurance sports. The below discussion is based off a paper by Dr. Timothy Noakes, who is professor of Exercise and Sports Science at the University of Cape Town and a leading authority in the discipline exercise physiology.
Believe it or not, prior to 1969, runners who were competing in marathons were advised against drinking during exercise and accepted recommendations for cyclists were “avoid drinking when racing, especially in hot weather. Drink as little as possible, and with the liquid no too cold. It is only a question of will power. When you drink too much you will perspire, and you will lose your strength… Four small bottles for a long stage (of the Tour de France), it is frowned upon to drink more.” The thing that is most amazing about this- there is NO published data that shows in either case, that the athletes performance suffered. In a book titled “Racing the Antelope,” Bernd Heinrich put forth: humans have evolved specifically to undertake prolonged exercise in the heat: “the fact that we, as savannah-adapted, animals have such hypertrophied sweating responses implies that, if we are naturally so profligate with water, it can only be because of some very big advantage. The most likely advantage was that it permitted us to perform prolonged exercise in the heat… What we do need sweating for is to sustain running in the heat of the day- the time when most predators retire to the shade.”
Noakes puts forth: since early humans likely ran in condition in which water was scarce, it seems highly probably that this evolving capability must also have included the capacity to preserve water stores and to resist the adverse consequences of developing a water deficit.
In 1977, Wyndham stated: “Dehydration materially affects the ability of the human body to regulate body temperature. This is well shown in studies in my laboratory. Those runners who drank sufficient water to keep their dehydration <3% of body mass had rectal temperature of around 38.5oC (101.3o F) at the end of a 30km race… in those who did not… there was a significant positive correlation between increasing rectal temperature and the extent of dehydration.”
Later that year, Costill put forth “In general, it seems that the large sweat losses incurred during training and marathon competition are adequately tolerated by the runner, with concomitant adjustments in the water and electrolyte distributions of the runner’s body fluid compartments.”
There were two significant events that stimulated new guidelines for fluid ingestion during endurance exercise:
1. The development of sports drinks with the goal of “replacing fluids that were lost due to sweating, which would cause a loss of circulating blood that would adversely affect the ability of the body to dissipate heat.“
2. The aforementioned work by Wyndham that implied “dehydration from sweating places humans at risk of heat stroke unless they drink sufficiently to maintain <3% and especially <5-6% dehydration during exercise.”
In 1992, Montain and Coyle presented work that was widely interpreted as proof that athletes who do not drink at sweat-replacement rates during exercise are at a disadvantage since they finish with a slightly higher body temperature and heart rate.
All of the aforementioned work lead to the 1996 American College of Sports Medicine (ACSM) to issue new guidelines:
1. Individuals should be encouraged to consume the maximal amounts of fluids during exercise that can be tolerated without gastrointestinal discomfort up to a rate equal to that lost from sweating, without reference to the dictates of thirst to optimize an athletes performance and minimizes their risks of ill health.
2. “It is clear that perception of thirst, an imperfect index of the magnitude of fluid deficit, cannot be used to provide complete restoration of water lost by sweating. As such, individuals participating in prolonged intense exercise must rely on strategies such as monitoring bodyweight loss and ingesting volumes of fluid during exercise at a rate equal to that lost from sweating, i.e. bodyweight reduction, to ensure complete fluid replacement.
3. The fluid intake range of 600-1200 mL/hour given in reference to maintaining a steady source of glucose during prolonged exercise.
Two major issues with the ACSM’s guidelines are they are not taking into account the number of slower athletes who take the time to ingest large volumes of fluids and that they are blanket guidelines for the rates of fluid replacement for all athletes regardless of gender, mass, surface area, level of fitness, acclimatization, sweat rate, intensity of exercise and environmental conditions in which they exercise.
The science behind these assumptions made by the ACSM has some flaws, which are:
• The 1992 study by Montain and Coyle did not measure the effects of drinking at different rates and how that impacted exercise performance.
• The studies have not taken into account the effects of the eight penalty incurred on performance
• None of the studies have been compared to the usual practice of drinking ad libitum (free drinking to personal thirst satisfaction).
In a review of the currently published research shows that drinking ad libitum produces at least equivalent outcomes to drinking to replace all the weight lost as sweat.
Another erroneous conclusion is that when an athlete who has lost eight during exercise collapses, then the weight loss (dehydration) must have caused the collapse. The problem is, most athletes who do not collapse during exercise have also lost weight and are also dehydrated. Therefore, dehydration cannot be the exclusive cause of collapse.
A 2004 study by Sharwood (Weight changes, medical complications, and performance during an Ironman triathlon) has provided NO evidence that those who finish prolonged exercise with the highest degree of weight loss are at the greatest risk of illness in ironman triathlons. Instead, the studies have consistently shown that athletes who lose the most weight during triathlons finish faster than those who lose little or gain weight.
Maintenance of body weight is not the only variable that is physiologically regulated during exercise. Perhaps a more important physiological variable that is regulated is fluid balance to ensure a constant plasma osmolality before, during and after exercise. The mechanism that controls plasma osmolality is the thirst mechanism, which is triggered to ensure the regulation of plasma osmolality.
With that being said, Noakes recommends that: “slower athletes need only to be advised to drink according to the dictates of their thirst during exercise, but not to ignore thirst. When athletes drink according to thirst, the risk that they will over-drink and so develop exercise-associated hyponatraemia is minimized and there is no evidence that they are at any significant disadvantage from the 3-5% level of dehydration that they develop as a result.
So what does this mean to you? In endurance sport events that last longer than 1.5 h ours, carbohydrate (CHO) replacement becomes important. As we get up to the 4+ hour mark (marathon, half-ironman, ironman and ultra-distance events), CHO replacement becomes essential to maintain performance. A normal source of CHO during endurance sports is in the form of a sports drink due to the ease of ingestion while moving. So there is a fine line between drinking to thirst, while still taking in enough calories. The take home message is, drinking to thirst (ad libitum) is the way to hydrate during endurance sports as long as you have a nutritional plan to consume enough calories to sustain your performance.
Noakes TD. Hydration in the Marathon. Sports Med 2007; 37 (4-5): 463-466
Believe it or not, prior to 1969, runners who were competing in marathons were advised against drinking during exercise and accepted recommendations for cyclists were “avoid drinking when racing, especially in hot weather. Drink as little as possible, and with the liquid no too cold. It is only a question of will power. When you drink too much you will perspire, and you will lose your strength… Four small bottles for a long stage (of the Tour de France), it is frowned upon to drink more.” The thing that is most amazing about this- there is NO published data that shows in either case, that the athletes performance suffered. In a book titled “Racing the Antelope,” Bernd Heinrich put forth: humans have evolved specifically to undertake prolonged exercise in the heat: “the fact that we, as savannah-adapted, animals have such hypertrophied sweating responses implies that, if we are naturally so profligate with water, it can only be because of some very big advantage. The most likely advantage was that it permitted us to perform prolonged exercise in the heat… What we do need sweating for is to sustain running in the heat of the day- the time when most predators retire to the shade.”
Noakes puts forth: since early humans likely ran in condition in which water was scarce, it seems highly probably that this evolving capability must also have included the capacity to preserve water stores and to resist the adverse consequences of developing a water deficit.
In 1977, Wyndham stated: “Dehydration materially affects the ability of the human body to regulate body temperature. This is well shown in studies in my laboratory. Those runners who drank sufficient water to keep their dehydration <3% of body mass had rectal temperature of around 38.5oC (101.3o F) at the end of a 30km race… in those who did not… there was a significant positive correlation between increasing rectal temperature and the extent of dehydration.”
Later that year, Costill put forth “In general, it seems that the large sweat losses incurred during training and marathon competition are adequately tolerated by the runner, with concomitant adjustments in the water and electrolyte distributions of the runner’s body fluid compartments.”
There were two significant events that stimulated new guidelines for fluid ingestion during endurance exercise:
1. The development of sports drinks with the goal of “replacing fluids that were lost due to sweating, which would cause a loss of circulating blood that would adversely affect the ability of the body to dissipate heat.“
2. The aforementioned work by Wyndham that implied “dehydration from sweating places humans at risk of heat stroke unless they drink sufficiently to maintain <3% and especially <5-6% dehydration during exercise.”
In 1992, Montain and Coyle presented work that was widely interpreted as proof that athletes who do not drink at sweat-replacement rates during exercise are at a disadvantage since they finish with a slightly higher body temperature and heart rate.
All of the aforementioned work lead to the 1996 American College of Sports Medicine (ACSM) to issue new guidelines:
1. Individuals should be encouraged to consume the maximal amounts of fluids during exercise that can be tolerated without gastrointestinal discomfort up to a rate equal to that lost from sweating, without reference to the dictates of thirst to optimize an athletes performance and minimizes their risks of ill health.
2. “It is clear that perception of thirst, an imperfect index of the magnitude of fluid deficit, cannot be used to provide complete restoration of water lost by sweating. As such, individuals participating in prolonged intense exercise must rely on strategies such as monitoring bodyweight loss and ingesting volumes of fluid during exercise at a rate equal to that lost from sweating, i.e. bodyweight reduction, to ensure complete fluid replacement.
3. The fluid intake range of 600-1200 mL/hour given in reference to maintaining a steady source of glucose during prolonged exercise.
Two major issues with the ACSM’s guidelines are they are not taking into account the number of slower athletes who take the time to ingest large volumes of fluids and that they are blanket guidelines for the rates of fluid replacement for all athletes regardless of gender, mass, surface area, level of fitness, acclimatization, sweat rate, intensity of exercise and environmental conditions in which they exercise.
The science behind these assumptions made by the ACSM has some flaws, which are:
• The 1992 study by Montain and Coyle did not measure the effects of drinking at different rates and how that impacted exercise performance.
• The studies have not taken into account the effects of the eight penalty incurred on performance
• None of the studies have been compared to the usual practice of drinking ad libitum (free drinking to personal thirst satisfaction).
In a review of the currently published research shows that drinking ad libitum produces at least equivalent outcomes to drinking to replace all the weight lost as sweat.
Another erroneous conclusion is that when an athlete who has lost eight during exercise collapses, then the weight loss (dehydration) must have caused the collapse. The problem is, most athletes who do not collapse during exercise have also lost weight and are also dehydrated. Therefore, dehydration cannot be the exclusive cause of collapse.
A 2004 study by Sharwood (Weight changes, medical complications, and performance during an Ironman triathlon) has provided NO evidence that those who finish prolonged exercise with the highest degree of weight loss are at the greatest risk of illness in ironman triathlons. Instead, the studies have consistently shown that athletes who lose the most weight during triathlons finish faster than those who lose little or gain weight.
Maintenance of body weight is not the only variable that is physiologically regulated during exercise. Perhaps a more important physiological variable that is regulated is fluid balance to ensure a constant plasma osmolality before, during and after exercise. The mechanism that controls plasma osmolality is the thirst mechanism, which is triggered to ensure the regulation of plasma osmolality.
With that being said, Noakes recommends that: “slower athletes need only to be advised to drink according to the dictates of their thirst during exercise, but not to ignore thirst. When athletes drink according to thirst, the risk that they will over-drink and so develop exercise-associated hyponatraemia is minimized and there is no evidence that they are at any significant disadvantage from the 3-5% level of dehydration that they develop as a result.
So what does this mean to you? In endurance sport events that last longer than 1.5 h ours, carbohydrate (CHO) replacement becomes important. As we get up to the 4+ hour mark (marathon, half-ironman, ironman and ultra-distance events), CHO replacement becomes essential to maintain performance. A normal source of CHO during endurance sports is in the form of a sports drink due to the ease of ingestion while moving. So there is a fine line between drinking to thirst, while still taking in enough calories. The take home message is, drinking to thirst (ad libitum) is the way to hydrate during endurance sports as long as you have a nutritional plan to consume enough calories to sustain your performance.
Noakes TD. Hydration in the Marathon. Sports Med 2007; 37 (4-5): 463-466
Wednesday, July 15, 2009
The Road to Kona; Chicago Edition #5
I have to admit that this year’s Tour de France has captivated me. After we get up and take our dogs out, I turn on Versus to catch the live action. You can see all the top professional riders sail up the mountains with grace and speed. Who wasn’t amazed to see Alberto Contador climb the Pyrenees? I of course was rooting for Lance to follow Alberto, but those days will come in the Alps.
I often think of myself on those rides. Then you actually look at course profiles. The 112-mile Ironman leg seems like a warm up to most days on the Tour. Even the famous 12 mile climb to Hawi woul
d be a nothing to the pro teams. Of course, I am not 120 lbs like Alberto or even the 160 lbs of Lance. As you can see from the photo, I am more like 5’9” and185lbs. Not exactly the body type of a climber. But I do have a love of riding at my speed and my abilities. The past few weeks we’ve been riding 3 to 3 1/2 hours on the weekends for my personal tour. While I might not fly up the hills, I make it up all the same. My overall goal for Kona is to finish, and getting through 112 miles on my bike will be a great accomplishment.
This past week I also started to focus on my swim with Break Through's Triathlon Swim Program. Mostly I have been swimming by myself at the West Loop Athletic Club, While they have a nice pool, there really is no substitute for group swims. I particularly value Ryan’s individual attention and small group sizes. Hopefully I can see a big improvement from my 1 hour 20 minute Ironman Arizona swim time…
Till next week - Go Lance!
I often think of myself on those rides. Then you actually look at course profiles. The 112-mile Ironman leg seems like a warm up to most days on the Tour. Even the famous 12 mile climb to Hawi woul
d be a nothing to the pro teams. Of course, I am not 120 lbs like Alberto or even the 160 lbs of Lance. As you can see from the photo, I am more like 5’9” and185lbs. Not exactly the body type of a climber. But I do have a love of riding at my speed and my abilities. The past few weeks we’ve been riding 3 to 3 1/2 hours on the weekends for my personal tour. While I might not fly up the hills, I make it up all the same. My overall goal for Kona is to finish, and getting through 112 miles on my bike will be a great accomplishment.This past week I also started to focus on my swim with Break Through's Triathlon Swim Program. Mostly I have been swimming by myself at the West Loop Athletic Club, While they have a nice pool, there really is no substitute for group swims. I particularly value Ryan’s individual attention and small group sizes. Hopefully I can see a big improvement from my 1 hour 20 minute Ironman Arizona swim time…
Till next week - Go Lance!
Monday, July 6, 2009
Sports Drinks and Caloric Intake
Let me be as clear as I can upfront- G2 is NOT a "sports" drink and will NOT provide you with enough calories to sustain any workload short of 1 hour. G2 is Gatorade's answer to Nuun and Zym who provide an electrolyte tablet that dissolves in water, replenishing electrolytes without the calories. So why am I making such a big deal about this?
This season, I have found myself telling too many athletes that G2 is not a sufficient calorie source for workout. In general, athletes that are training for an event that will last longer than an hour (1/2 marathon or longer, Olympic distance triathlon or longer, etc…). If your sports drink does not contain at least 200 calories per 20 oz serving.
Here are the Nutritional Facts for some common sports drinks, per 16 ounces (the standard large water bottle is 24 ounces):
The numbers above are pretty clear, Gatorade might not have enough calories to sustain your workouts and/or races depending on the intensity and duration. In general, athletes should be taking in 200-400 calories per hour depending on the athletes size and the intensity of the race. That would be close to two (2) bottles of Gatorade Endurance, three (3) bottle of G2 or perhaps one (1) bottle of Infinit. If you are taking in more than one (1) bottle per hour, you are going to spend a significant amount of time in the restroom during the race.
This season, I have found myself telling too many athletes that G2 is not a sufficient calorie source for workout. In general, athletes that are training for an event that will last longer than an hour (1/2 marathon or longer, Olympic distance triathlon or longer, etc…). If your sports drink does not contain at least 200 calories per 20 oz serving.
Here are the Nutritional Facts for some common sports drinks, per 16 ounces (the standard large water bottle is 24 ounces):
The numbers above are pretty clear, Gatorade might not have enough calories to sustain your workouts and/or races depending on the intensity and duration. In general, athletes should be taking in 200-400 calories per hour depending on the athletes size and the intensity of the race. That would be close to two (2) bottles of Gatorade Endurance, three (3) bottle of G2 or perhaps one (1) bottle of Infinit. If you are taking in more than one (1) bottle per hour, you are going to spend a significant amount of time in the restroom during the race.
Sunday, July 5, 2009
The Road to Kona; Chicago Edition #4
Well, it looks like summer is still trying to arrive in Chicago. We've had a couple of hot days, but also a lot of rain forcing me to spend more time on my Computrainer than I'd like. Sometimes the trainer is appealing since it so easy to set up and not worrying about traffic, although I personally find it very tough to ride indoors longer than two hours. When the weather is good, we've been able to get in some solid outdoor rides of 3 - 4 hours, followed by transition runs. We particularly like the "LaGrange hilly" ride starting in downtown LaGrange.
A link from my facebook page to the course profile is here.Not bad a bad ride considering the 2,200 feet of elevation gain for the flat Chicago area. Plus, there is a Chipotle near the start / finish line for a post workout burrito...
This week's training:
Two big events this week. The first is that I am starting Break Through's Triathlon Swim Program on Monday. Yes, it starts at 5:30 am every Monday and Friday morning. The good side is that I'll get my swim workouts in before the day starts, the bad side is that it will be a real effort for me to get up that early. The second is a big workout Saturday, with a 2900 yard swim, 3.5 hour ride, then a 40 minute transition run.
Upcoming races:
I am planning on racing the Whirlpool Steelhead 70.3 on August 1st. My main goal for this race is to practice my nutrition on the bike, a key weakness I had during Ironman Arizona last year. I'll discuss more about this in my next blog....
A link from my facebook page to the course profile is here.Not bad a bad ride considering the 2,200 feet of elevation gain for the flat Chicago area. Plus, there is a Chipotle near the start / finish line for a post workout burrito...
This week's training:
Two big events this week. The first is that I am starting Break Through's Triathlon Swim Program on Monday. Yes, it starts at 5:30 am every Monday and Friday morning. The good side is that I'll get my swim workouts in before the day starts, the bad side is that it will be a real effort for me to get up that early. The second is a big workout Saturday, with a 2900 yard swim, 3.5 hour ride, then a 40 minute transition run.
Upcoming races:
I am planning on racing the Whirlpool Steelhead 70.3 on August 1st. My main goal for this race is to practice my nutrition on the bike, a key weakness I had during Ironman Arizona last year. I'll discuss more about this in my next blog....
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