Building That Base Back

A friend recently told me that he hasn’t been impressed lately with my blog. Well, hopefully that will change soon. I’ve been trying to get back into good training for a while now. This month I’ve had to focus on the basics: building that base back. At the beginning of April I saw how high my heart rate was for the power I was putting out, and knew that my base had really crumbled. I’ve established a huge base before by focusing on the bike. This month I did Ironman St George, which was a phenomenal event that I limped through with a 6:19 marathon to finish in 13:39. I really needed that finish because besides a poor base I’ve had a series of DNFs and DNSs this year and was starting to feel I was losing that drive to push on. Two weeks after Ironman St George I went to Sacramento to ride in the Train of Pain with Canari-Navy Cycling. There is a great blog telling many of the stories of the ToP, so instead of reiterating them just read the blog. On day 3 of the Train of Pain, I noticed my heart rate was coming down for the effort, which was rather encouraging. My goal was to increase the amount of Zone 2 riding I was doing, but more importantly was decreasing the amount of zone 1. With group rides, and long rides it is tough to not get a lot of zone 1 riding in. You need those breaks for when it’s time to pull or surge, or just to try to hang when others surge. Here is my power distribution from 5/7 through 5/26 (minus three days of ToP when I was riding without my powertap):

In my previous post I showed that I had just over 35% in Zone 2, and 34% in Zone 1. Interestingly, Zones 3 and 4 dropped a little, Zone 5 remained the same, and Zone 6 increased a bit. Overall I’m rather pleased with the boost to my fitness I’ll reap from the Train of Pain, and as soon as I recover will start pouring in the Zone 3 and 4 training.

My ToP stats (5 consecutive day totals): 464.31 miles, 33,038 ft of climbing

	Avg HR	Max HR	Normalized Power
Ironman St George			239
ToP Day 1	136	162	249
ToP Day 2	112	143
ToP Day 3	132	156
ToP Day 4	121	173
ToP Day 5	130	156	263

Two Week Power Distribution

Yesterday when I got back from a 2.5 mile run in the heat at St George, my hotel neighbor, a 60 year old Ironman from Germany, teased me saying that it was too late to start getting ready. Yes, it is. Last Sunday at the Spring Sprint I was talking to Jim Vance, telling him I was going out to do St George. He smirked and commented that it would be a training day. He knows me well, because those were my thoughts exactly. It’s hard to consider an Ironman a training day, because it is such a unique experience, but I have to look forward. My goal on the bike is to take it take it easy and contribute more to my Zone 2 work. That may also sound silly since even a fast Ironman race is primarily Zone 2 work, but I’ll be shooting for the lower end of the zone rather than the upper end.

For the past two weeks I have been trying to get more zone 2 work in, and here is the power distribution I have:

Only about 35% is in Zone 2. I am hoping to show in a couple weeks that I’ve pushed that up closer to 50%, with the Zone 1 work coming down from 34%.

Why Zone 2? I need to reestablish my aerobic base, which will happen faster by doing long lower power rides. Zone 1 could do that, but I also want to start improving my FTP. As my aerobic base returns, I will focus on more Zone 3 and 4 work to push my FTP up with shorter workouts. The ‘sweet spot’ for power training includes Zones 2-4, but the lower the power the longer the exercise has to be to have any impact on FTP. Also, building FTP purely with Zone 2 work really only prepares you for the longest rides.

Heat Training and Heat Injury, Part 2

In my previous post I left you with this chart:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

    

This chart is an estimation of the cardiac output distribution in four different scenarios. Cardiac output is the flow rate through the heart, which is the product of the heart rate and the stroke volume (CO=HR*SV). Heart rate, as you know, increases with exercise, but also increases with other stressors such as elevated core temperature. Stroke volume also increases with exercise (in a healthy individual such as an athlete). The height of each column in the chart depicts the cardiac output whether cool or hot, and whether at rest or exercising. When cool at rest, cardiac output is about 5 liters per minute, and the majority of that blood flow is sent to your organs that require a fairly consistent amount of blood flow to function. When hot at rest cardiac output increases to send more blood to the skin for cooling. The viscera and muscle blood flow does not change much. Exercise drastically increases cardiac output to near your physiologic maximum to meet the demand to the muscles, and also sends more blood to the skin for cooling. If you are hot while exercising, your body is forced to send even more blood to the skin for cooling, and must steal that blood from your muscles.

When you are hot you cannot exercise as effectively because you cannot deliver the amount of blood to your muscles as you can when you are cool. But what about acclimatization? Acclimatization is a progressively improving physiologic response to exercising in heat. An unacclimatized person can produce about 1 liter of sweat per hour whereas an acclimatized person initiates sweating earlier and can sweat 2-3 liters per hour. An acclimatized person also produces much more aldosterone which conserves sodium from the sweat. An unacclimatized person sweating profusely can lose 15-30 grams of sodium in a day. An acclimatized person on the other hand will only lose 3-5 grams of sodium in a day, even though they are sweating more!

There is still a lot of talk about high level of salt intake in our sport. Usually people are concerned about “cramping” from low sodium. This remains a controversial topic among coaches and athletes, but to contribute to the controversy I will give my opinion here (and in my next post). Unfortunately most of the opinions you read are stated as fact by people with no scientific background.

The typical logic goes like this: There is salt in my sweat. I sweat more when I exercise in the heat. I need to replace that salt. If I don’t replace that salt I will cramp. When that person experiences cramping they fall back on that they should have eaten more salt. The same logic happens when people feel tired and they assume they should have eaten more food. We like to look for the easy fix, in this case salt tabs. What about training?

Studies have been done on Ironman athletes comparing those that take in high levels of salt, and those that do not. Their plasma sodium levels are not appreciably different, and either are their cramping experiences. The difference is the amount of sodium in their sweat. The more salt they take in, the more they excrete in their sweat. An acclimatized person however should have a high plasma aldosterone and be retaining their sodium. What happens with a high salt diet? You could probably guess it. Plasma aldosterone levels are reduced. Your body is trying to get rid of that extra salt load in your sweat and urine. Doesn’t it make sense to utilize your training and acclimatization rather than fight it?

The unacclimatized individual will lose more salt, and when forcing fluids is at greater risk of having problems such as hyponatremia so may consider increasing salt intake during the acclimatization period if it is hot and the training or event is long (>3 hours). This is not your typical well trained athlete however. What about the 3-4 grams of sodium an acclimatized athlete loses? Well, a modest amount of sodium intake is fine, which occurs anyway when drinking sports drink and eating food.

And what about cramping? I will address that in the next part.

How do you go about becoming acclimatized? Simply by being aerobically fit you are ahead of the game. Especially if you have years of aerobic exercise experience, your heart is likely more efficient, and able to deliver a higher cardiac output (due to a larger stroke volume). Even when exercising in cool weather your body has to adapt to cooling, so just by being aerobically fit you are somewhat more acclimatized than an inactive individual. Larger people have more trouble cooling because of a lower surface area to body mass ratio, and fat in insulating. Losing excess body weight can also assist in cooling. The acclimatization that we are primarily looking for though occurs when the body is exercised in heat. This is best done progressively. Acclimatization actually begins early (the first week of heat training), but the full effect can take up to six weeks, and if done cautiously and progressively can actually take longer. During particularly hot periods (heat waves) there can be progressive sodium loss and progressive dehydration, so taking some easier days and avoiding exercising in the hottest part of the day for several consecutive days is prudent.

What is the fate of the athletes at Ironman St George? It is so early in the season that most of us have not had the opportunity to acclimatize well. There will still be people that race well, but I anticipate a large attrition from the heat.

In the next part I will address heat injuries.

Heat Training and Heat Illness, Part 1

I arrived today in St George, Utah, two days before the St George Ironman. I had signed up for this event several months ago when I had aspirations of being in top shape and chasing a Kona spot. Since then training hasn’t gone so well, but I’ve decided to show up anyway because the opportunity to participate in an Ironman is pretty awesome.

After checking in for the race and settling in the hotel, I decided to go for a short run. Immediately I was blow away by how hot it was. According to wunderground.com, the max temp today was 87 degrees, with a historical average for May 5 of 67 degrees, and prior record temp of 83 degrees in 1989. Last year at the inaugural Ironman St George there were problems with cold water temperatures and high winds. There was almost no wind today, and the water temperature today was reported as 65 degrees. What is the predicted high temperature for Saturday? 92 degrees!! Apparently we won’t have to worry about a cold race.

Writing this post will not change any suffering that occurs on Saturday. I’ve decided to write on this topic because clearly we are entering the hot season again. At its worst, heat kills. Even without significant heat injury, heat drastically affects the performance of endurance athletes. Although we frequently have to deal with this natural phenomenon, I have found that how heat affects our physiology during exercise is not well understood by most athletes.

You probably know that the average normal core body temperature is approximately 98.6 F (37 C). There is some individual variation of this, but overall the hypothalamus acts to maintain a core temperature at which your body will function well at. It is normal though for our core temperature to be lower (even less than 97 F) in the early morning, or during cold weather. During hard work, strong emotions, and occasionally in some normal adults and active children, core temperature can sit higher at 99-101 F. Exercise is not very efficient, with over 80% of the energy that we expend during exercise being converted to heat rather than work, and during hard exercise our core temperatures normally will rise to 101-104 F. Although the temperature is elevated, it is not a “fever”, which is a resetting of the hypothalamic set point to a higher temperature (most commonly induced by chemical messengers released in response to an infection). So, don’t bother trying to take Tylenol to lower you body temperature when you exercise. It will not work.

Even at rest, we are generating a lot of heat, mostly from deep organs. During exercise there is much more heat being generated from skeletal muscle contractions. This heat must be transferred to the skin where it can be lost to air. The rate of heat loss depends on how rapidly heat can be transferred from the core to the skin AND how rapidly heat can be transferred from the skin to the surroundings. To increase the amount of heat transferred to the skin (as is needed in exercise) the blood flow to the skin must increase, pure and simple.

Transferring heat from the skin to the environment occurs with the four mechanisms of heat transfer (flashback to physics): radiation, conduction, convection, and evaporation. Don’t tune out if you are already feeling confused. I’ll try to take the mystery out of these.

Radiation is loss of heat in the form of infrared heat rays. This is important to understand. Every object (be it your body, the pavement, or a lava rock) will radiate heat in the form of infrared heat rays. When you look through night vision goggles this is evident because objects that are radiating more are more visible in contrast to the cooler surroundings. Although a lot of heat is lost from the body by radiation, there is heat also radiating towards the body. If the temperature of the body is greater than the temperature of the surroundings, more heat is radiated away from the body than towards it. How significant is this? It can be very significant. It is estimated that a nude person in a room that is at 70 F will lose 60% of their total heat loss by radiation.

Conduction is heat loss that occurs when the body is in direct contact with objects or air that is of lower temperature than body temperature. A nude person in a room at 70 F loses about 3% of total heat loss by conduction.

Convection is heat loss that occurs by conduction to air, which is then carried away by convection air currents. This can be a very significant portion of total heat loss, and depends on the wind velocity. The cooling effects of wind is proportional to the square root of the wind velocity, i.e. a 4 mph wind is twice as effective as cooling as a 1 mph wind.

Evaporation is heat loss that occurs when water evaporates from the skin or lungs. Evaporative heat loss can be increased by sweating and becomes essential in high temperatures. High humidity impedes evaporation, often resulting in dripping sweat which has the effect of causing dehydration without cooling.

In response to excess heat, there is direct stimulation of the anterior hypothalamus which causes nerve impulses that result in increased sweating. Sweating can increase heat loss 10 fold. The posterior hypothalamus also acts to cause nerve impulses that result in dilation of the blood vessels in the skin, increasing blood flow from nearly nothing to 30% of total blood flow! This increases the heat transfer from organs to the skin. I will leave you now with the graphical representation of this to contemplate, and pick up the rest of this topic in another part.

Spring Beginnings

I know, I know, I know…. No posts for a while!

This week about a dozen people have asked me about my recent silence. Well, if DNF, DNS and unusually poor performance hasn’t caught your attention, then apparently my silence has. Training hasn’t been going well for a few months. I have had a few things to write about, and I will not try to catch up on them all now. That would lead to a long post (laden with excuses) that wouldn’t catch much interest. Instead, a short post on getting back into training, or just starting training.

You can train based on a periodized schedule, but the first thing that is of crucial importance to anyone that wishes to move ahead is establishing a routine. This is easier to do if you are only training for one sport, but essentially the principles are the same for triathlon. What I recommend is looking at the time blocks you have available to train and try to go through the motions of getting in some exercise, daily. The amount and type of exercise is much less important than getting out there and doing something.

This is what I’ve been trying to do for several weeks now. Last week I had my first week of exercise everyday since the second week in January. For several weeks prior I worked out 2-5 days, many days only about 30 minutes. Again, the length of the workout was not nearly as important as establishing a daily routine. Even 10 minutes can help you establish a routine that you become used to.

Now that it is May 1, I am beginning to develop some training goals for this month. I have noticed a huge drop in my aerobic fitness with my heart rate 10 beats/min higher for the same power as I had seen previously. My FTP has also taken a tumble, with a high of 340 last Fall, to 307 at the beginning of March, to 296 currently. My CTL has also dropped from a high of 147.3 on 8/8/2010, back to another peak of 145 on 12/31/2010, to a low of 67.6 on 4/21/2011. A CTL of 68 doesn’t tell the whole story though, because some people couple probably muster up a decent (short) race with that, but it is what your CTL is “made of”. Mine was made of sitting around eating donuts, with the occasional easy workout to keep my fitness from plummeting to zero.

My training in May is essentially to reestablish my aerobic base, with a large focus on cycling. I will do this with a lot of zone 2 riding. The good new is that once I have that aerobic base back, my training can begin to shift to more quality workouts without being up at a peaked CTL.

Thanks for hanging in there with me, and I look forward to seeing you at the races.