Heat and power

[tomUK]

sorry to 'flood' the board as of recent but I want to ask a question about heat and power...

assuming wind and total humidity were the same;

If I were to ride a 10 mile route in 50 degrees at then the same route in 100 degree, both at in the same time then my kJ would be pretty equal; however, the heat would make it feel MUCH harder and therefore I assume there is an added stress in the body at some level (it is this level i'm trying to understand). Does this add any training benefit other than acclimatizing to the conditions? i.e. does it incur any 'stress' factor?

 

[doctorSpoc]

"Does this add any training benefit other than acclimatizing to the conditions? i.e. does it incur any 'stress' factor?"

Conventional wisdom and in my personal experience.. no. in the heat, your body experience more strain.. but the if you ride at the same power for two rides your logging the same exercise "stress" and therefore will reap the same adaptations since the adaptations are correlated to a dose of exercise stress.. not strain.. and is why power is a much better tool than something like HR which as well measures strain, not stress...

based on my own personal experiences over many seasons with inside training, where cooling is vital in order to hit higher power number.. you really do improve more by just doing whatever you can to ride higher numbers.. even thought at a given power with better cooling the interval hurts a lot less.. similarly outside.. it's better to ride in mornings and evening outside of the heat in order to hit higher power numbers.. anyway, in my experience perceived exertion or how much a workout hurts is not what you should go with at all.. the only thing that really matters is how much power you did for how long..

that said, acclimatize to the conditions is important, but i think that's what riding in the heat gives you it doesn't add a factor to your workout.. you're much better off to ride enough in the heat for acclimatization.. once or twice a week like you would do race simulation... and the rest of the week avoid it and get your high numbers..

 

[tomUK]

Thanks for that. A few questions...

Would I therefore be correct in saying 'strain' has little value in making you stronger?

Training in the afternoon heat (bearing in mind that no race/rides generally start then) may actually be hindering me getting strong as I would *guess* the ability to reach higher wattage numbers is both a combination of stress AND strain. Less strain would therefore mean more more stress could be added?

Also in relation to your statement about perceived exertion, is not a good indicator of needing rest? From what I've read it seems that if you just can't push the numbers out that you are looking for then you are most likely tired and need some downtime?

 

[doctorSpoc]

Originally Posted by tomUK .

Would I therefore be correct in saying 'strain' has little value in making you stronger?


Not really.. strain is just not the measure you should be interested in.. strain is as a result of stress.. strain accompanies stress.. it's just not necessary to measure it because you can measure stress directly (power) and measuring strain has all kinds of error associated with it because it's so variable, since it can be affected by so many outside factors.. e.g. heat, training load, fatigue, dehydration, time of day etc.. measuring/considering stress informs you of what you actually did.. then you can say based on analysing you files.. if I put in x stress I get y performance

you want to predict, or take measure of training 'stress' because it is correlated well with resulting adaptations and it's an objective measure that will not be impacted by outside factors.. it lets you know what you actually did and how much it will improve performance.. not how much it hurt.. how much it hurt will vary from day to day so it's just not the thing you want to be measuring..

don't know if that came out as plainly as i would like..


Originally Posted by tomUK . Training in the afternoon heat (bearing in mind that no race/rides generally start then) may actually be hindering me getting strong as I would *guess* the ability to reach higher wattage numbers is both a combination of stress AND strain. Less strain would therefore mean more more stress could be added?

yes.


Quote:
Originally Posted by tomUK .

Also in relation to your statement about perceived exertion, is not a good indicator of needing rest? From what I've read it seems that if you just can't push the numbers out that you are looking for then you are most likely tired and need some downtime?

no, wasn't saying that... probably didn't write that as well as I could have... just kind of hammer these responses out... sometimes they come out clear sometimes, not so much.. lol.. no time to edit them really.. sorry, maybe i should have written...perceived exertion/how much a workout hurts or perceived exertion i.e. how much a workout hurts..

what you've written here though explains why you should not consider strain as a measure of training load.. "if you just can't push the numbers out that you are looking for then you are most likely tired and need some downtime".. yes.. if you can't stress you body enough because the resulting strain would be too great to overcome you should go home.. it's the allotment of stress you can put out that you are interested it.. that's the number you're interested in.. in this case you have huge strain and low stress.. so low in fact that it's not even worth it to do the workout because the adaptations are related to the stress, not the strain.. yes..

 

[awilki01]

FWIW, I posted something similar in the Wattage Google Email group. I was doing some TT testing/workouts in the heat and was having issues generating the power. A couple people responded and stated that in their experience, they have noticed a drop of 1w in FTP for every degree F over 70F.

 

[swampy1970]

That's quite a lot and it surprises me. For constant training I'm not a fan of the heat - but at some point if you're racing in the heat you'll have to get some training rides in while it's hot just to get some idea how you cope with the heat, especially it you're rising time trials with an aero hat. Some training in seemingly oven like temps maybe required.

 

[awilki01]

Originally Posted by swampy1970 .

but at some point if you're racing in the heat you'll have to get some training rides in while it's hot just to get some idea how you cope with the heat

I did the Hotter'n Hell 100 last year in Wichita Falls, TX. It reached 109F that day (hottest on record for that ride from what I understand). I saw some people laid up in stretchers with IVs. I saw pics on the Internet of people having to take ice baths due to heat stress. It was scary! People were lining up along the road between rest stops to get in any shade they could find - which is rather sparse in that region of Texas. However, I purposefully rode in the heat of the day for a month or two before that event so I was extremely acclimated to it. I also did some 45 minute dry sauna sessions in 180F temps the week before the ride. I was perfectly fine in the heat then. Now, I just ride indoors on the rollers during the week so the heat really bothers me now when I ride outside on the weekends. I've read some literature stating that it takes about 10 - 14 days to get your body acclimated to the heat.

 

[HillyGoat]

http://www.floridacyclingmagazine.com/current-issue-1.html


The above link is an online cycling magazine that has some good info on racing in the heat. We lose power in the heat, no denying that. You can mitigate the loss but it happens. I did a TT last Tuesday evening in 95 degree heat and was down 20 watts. Part of the power loss was likely due to a hard morning ride and part was due to being in the TT position but I believe some of the power loss was due to the heat.

 

[An old Guy]

Originally Posted by tomUK .

sorry to 'flood' the board as of recent but I want to ask a question about heat and power...

assuming wind and total humidity were the same;

If I were to ride a 10 mile route in 50 degrees at then the same route in 100 degree, both at in the same time then my kJ would be pretty equal; however, the heat would make it feel MUCH harder and therefore I assume there is an added stress in the body at some level (it is this level i'm trying to understand). Does this add any training benefit other than acclimatizing to the conditions? i.e. does it incur any 'stress' factor?

Your assumption that the stress is the same is wrong. Clearly your body is attempting to dump heat by sweating. That should show the stresses are different.

---

I did 12 miles in 100+ temeratures today before I drank any water. I don't think that 10 miles would be long enough for me to get a benefit of riding in the heat. (After about 2 hours I drink 20oz of water every 4 miles.)

I suspect that riding in the heat will improve your body's ability to process water.

I also expect that riding in the heat will help your mental state when you are hot, cold, dehydrated, short on food. Having gotten through bad patches helps in getting though bad patches.

---

Today was my 8th or 9th straight day in the heat. I felt really good at the end. Did not need as much water. My average power was up from the prior days. I did something right. I hope my body is helping.

 

[awilki01]

Quote:Originally Posted by An old Guy . 
Your assumption that the stress is the same is wrong. Clearly your body is attempting to dump heat by sweating. That should show the stresses are different.
 
---
 
I did 12 miles in 100+ temeratures today before I drank any water. I don't think that 10 miles would be long enough for me to get a benefit of riding in the heat. (After about 2 hours I drink 20oz of water every 4 miles.)
 
I suspect that riding in the heat will improve your body's ability to process water.
 
I also expect that riding in the heat will help your mental state when you are hot, cold, dehydrated, short on food. Having gotten through bad patches helps in getting though bad patches.
 
---
 
Today was my 8th or 9th straight day in the heat. I felt really good at the end. Did not need as much water. My average power was up from the prior days. I did something right. I hope my body is helping.


Your prescription of 20oz of water (assuming you mean straight water) every 4 miles is good way to get someone killed by hyponatremia!!! Go troll in some other forum!

 

[maydog]

I take most of AOGs comments with a gain of salt; that number seemed suspect to me as well. For giggles I looked back at my ride yesterday.

Temperature = mid 90's
Ride time = 90 minutes
Weight loss = 8 to 10 pounds
Water consumed = 2x32 ounce bottles = 4 pounds
Total perspired weight = 12 to 14 pounds = 184 to 215 ounces
Perspiration rate = 2 to 2.4 ounces per minute

For that ride, for a more or less steady rate of hydration I would need to take in 20 oz for every 10 minutes of riding. That's 3 miles at a reasonable pace. I think it would be impossible to stomach that much water - but I don't think it would kill me. If I allowed about 4 pounds of weight loss then it would be 20 oz for 4 miles, again this is much higher than what an average person could tolerate drinking. I can tolerate a bit more than a liter an hour, which is in line with this article I found:

http://www.badwater.com/training/bornhydration.html

Full disclosure, I am much larger than your average rider and I do tend to sweat a lot. That particular ride was a group ride at a brisk pace - I had trouble finding the opportunities to drink the water I had. I ended up reaching my threshold of water loss and started to cramp up a bit and lost a lot of power. I ended up loosing the group. The smaller, less sweaty individuals finished together.

One more thing, the ice slurry reccomendation in Dave Henderson's post saved my ride a few weeks ago. I was nearing the end of a 90 miler in intense heat and wind and was overheating on the brink of bonking. I stopped at a holiday gas station and bought a 44 oz slush drink, I chugged that thing until I could feel my insides get cold - almost like brain freeze. A few minutes later, I was feeling much much better.

 

[awilki01]

Yeah, but some people could have read that as 20 oz of water every 4 miles for an entire ride. That could kill you if you tried it without taking in any electrolytes.

I'm probably over-reacting, but that stuck out like a sore thumb to me. Some people are clueless about hyponatremia and may take what he said to heart and too literal.

 

[quenya]

On the flip side; tuesday night I did 43 miles in 94-96 degrees on one 32 oz bottle and had maybe 1/2 left over, last Saturday I did 92 miles with 11,000 feet of climbing in 70-86 degrees I drank 5 24oz bottles and 2 12oz Dr. Peppers.  My urine was very light before and after each ride.  I was not dehydrated in the least by either. Following AOG's plan Tuesday I probably would have drank about the same amount albeit all during my warm down, and Saturday I'd have drank 16+ bottles on the day.  

 

[swampy1970]

Originally Posted by awilki01 .


I did the Hotter'n Hell 100 last year in Wichita Falls, TX. It reached 109F that day (hottest on record for that ride from what I understand). I saw some people laid up in stretchers with IVs. I saw pics on the Internet of people having to take ice baths due to heat stress. It was scary! People were lining up along the road between rest stops to get in any shade they could find - which is rather sparse in that region of Texas. However, I purposefully rode in the heat of the day for a month or two before that event so I was extremely acclimated to it. I also did some 45 minute dry sauna sessions in 180F temps the week before the ride. I was perfectly fine in the heat then. Now, I just ride indoors on the rollers during the week so the heat really bothers me now when I ride outside on the weekends. I've read some literature stating that it takes about 10 - 14 days to get your body acclimated to the heat.

Can't remember if it was the 06 or 07 Death Ride but halfway up Carson Pass final big climb of the day, a thermometer in the shade of the rest stop read 105F. The 10 mph southwesterly wind felt like a damned hairdryer. Darned black shoes - my feet swelled up and had to ride with the velcro straps pretty much undone.

 

[awilki01]

Originally Posted by quenya .

On the flip side; tuesday night I did 43 miles in 94-96 degrees on one 32 oz bottle and had maybe 1/2 left over, last Saturday I did 92 miles with 11,000 feet of climbing in 70-86 degrees I drank 5 24oz bottles and 2 12oz Dr. Peppers. My urine was very light before and after each ride. I was not dehydrated in the least by either.
Following AOG's plan Tuesday I probably would have drank about the same amount albeit all during my warm down, and Saturday I'd have drank 16+ bottles on the day.

I'm sure you are taking in electrolytes of some sort as well, right? Or was that 16+ bottles just water and nothing else? /img/vbsmilies/smilies/eek.gif

 

[awilki01]

Originally Posted by swampy1970 .


Can't remember if it was the 06 or 07 Death Ride but halfway up Carson Pass final big climb of the day, a thermometer in the shade of the rest stop read 105F. The 10 mph southwesterly wind felt like a damned hairdryer. Darned black shoes - my feet swelled up and had to ride with the velcro straps pretty much undone.

Heat = respect. I don't take heat for granted after seeing others on those stretchers. Thankfully, I was fully acclimated at the time.

It's ironic, but I just read about the heat and performance issue. When you get hot, the body has to send more and more blood to the periphery so as to cool off the blood from the evaporating sweat. This leaves less available blood and oxygen for the muscles. Also, in these conditions, the muscles themselves can't dissipate heat as fast and this too hinders their performance. I may need to go back and reread that section of the book - I'm going off of memory at the moment. I'll come back and edit this if I misstated anything.

Back to the OP, I found this study on Google: http://www.sportsci.org/jour/0201/jpm.htm

The conclusion states:

In conclusion, well-trained cyclists show only small adaptations to a moderate heat-acclimation program. These adaptations probably have little impact on performance at normal environmental temperatures, but more research is needed to clarify this issue.

Personally, I find it hard right now (maybe because I'm not currently acclimated) to do hard intervals in the heat. I have to slow down. And, as a result of this, I don't feel I'm stressing my body enough to make subsequent adaptations to get faster. If you are acclimated and can maintain the proper power for the interval durations, I think it would be fine. But, personally, I think I'll either do them in the early morning or late in the afternoon right now when riding outdoors. Otherwise, it's on my rollers inside at 75 degrees or so. Long endurance rides can be done in the heat. Just make sure you can stay cool, hydrated, and get enough electrolytes and energy.

 

[tnsporting90]

Few days ago I ride 50 miles route in 50 degrees and then 100 miles in same degree after that I have experience that heat make it MUCH harder than
minimum low degree so I feel that it added stress on the body and I feel very tired .
Thanks.

 

[Felt_Rider]

Originally Posted by awilki01 .


Heat = respect. I don't take heat for granted after seeing others on those stretchers. Thankfully, I was fully acclimated at the time.

Personally, I find it hard right now (maybe because I'm not currently acclimated) to do hard intervals in the heat. I have to slow down. And, as a result of this, I don't feel I'm stressing my body enough to make subsequent adaptations to get faster. If you are acclimated and can maintain the proper power for the interval durations, I think it would be fine. But, personally, I think I'll either do them in the early morning or late in the afternoon right now when riding outdoors. Otherwise, it's on my rollers inside at 75 degrees or so. Long endurance rides can be done in the heat. Just make sure you can stay cool, hydrated, and get enough electrolytes and energy.

Saw a female cyclist being attended by an emergency crew today on my return.

What I normally try is a 2 x 60 on Sunday's after church, which puts me into the afternoon temps and today it was pushing 103 F. Part of not hitting good performance today was a 70 mile ride yesterday with 30 miles of that being in a very lively group, but the bigger part was the oven like feeling today. At least the humidity was low.

What I ended up with after a 40 mile round trip drive to get to a safe place the effort only amounted to 2 hours, 40 miles, 82 TSS at 0.58 IF...../img/vbsmilies/smilies/eek.gif/img/vbsmilies/smilies/frown.gif

I could have hit 80 TSS with about an hour on the rollers, training that would have amounted to something and saved gas money.....well ****!!

Oh and I thought I was doing okay during the 2 hour ride even though my intensity was low until I stopped at the end and I almost fell over. I was in worse condition from the heat than I thought.

 

[An old Guy]

Originally Posted by awilki01 .


Your prescription of 20oz of water (assuming you mean straight water) every 4 miles is good way to get someone killed by hyponatremia!!!Go troll in some other forum!

Like maydog said it may be necessary.

My current rides including Saturday, 100+ temps, are 2 hours plus 9 miles. Stand under the shower at 2 hours and drink 20oz of water. Drink 40oz of water during the next 9 miles. Drink more water on my drive home. It is fair to say that that amount of water contained about 1tablespoon of Gatorade power. Not much. And then carry a drink around the rest of the day.

---

Heat kills faster than over hydration.

 

[quenya]

Originally Posted by awilki01 .


I'm sure you are taking in electrolytes of some sort as well, right? Or was that 16+ bottles just water and nothing else? /img/vbsmilies/smilies/eek.gif

I didn't drink 16 bottles of water that's what AOG's hydration strategy would have had me do. It would have been overkill at least if not dangerous. I usually don't mix drinks with electrolytes, just maltodextrin powder, but when I'm out on rides long enough to need a refill I usually add Gatorade bought at a store and or a solid food with electrolytes. What I do is maintain my hydration 24/7.

In defense of my strategy I have very rarely had issues with hydration, and I've never had a muscle cramp. I don't advocate my own hydration strategy for others because I think nutrition and hydration strategy needs to be unique to the individual. But, I am alarmed when I hear of someone drinking metric tons of plain water or gobbling endrolytes/e-caps/whatever like candy.