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     Juerg Senior Member Username: Juerg Post Number: 1623 Registered: 04-2006 |
Here some thoughts and some observation on HR drift. 1. In intensities ( In FaCT names ) STF / FTF area we see very little HR dirct so the performance in wattage or speed, the HR and respiration rate often stay for very long time the same. What we see first is a Respiratory frequency drift , before we see a HR drift. There are for sure different reasons for that and one possible one to discuss is the situation, that in a 4 - 6 hour long workout on STF/ FTF there could be some "fatigue" just simply from the CNS and co-ordination wise or another part we often never think on from the core muscles. We divide the muscle system in a) stabilizer and b ) mobilizer. Actually if w I say we, thatn that's not true. We learned this from a much smarter "coach" . He developped some very interesting scoliosis therapy movement in the 1920. His name : Rudolph Klapp ( 1873 - 1949 ). His theories are fascinating and if I look in this days " fashion " courses like Pilates and other ideas, than it is interesting to see, that nobody ever mentions his work, as most of the "Core " exercises where developed by Klapp and just kopied over and over again and renamed and finally put out under different "Developpers'. Klapp started the idea on mobilizer and stabnilizer sysytems. In short. Stabilizer are here to , as the words tells us stabilize. Now in and y movement pattern , but for sure in sport there is something very important to this stabilizers. As weaker teh stabilizer, as more a person need to take mobilizer to actually stabilize. That means very simply put. All the mobilizer you use now to stabilize just simple can't contriobute to movments and speed and good performance. So what does this has to do with Heart rate drift. In long rides for example some people will start to develpp some " back - pain. and get "restless' , Usaing now morwe mobilizer to still stabilze on the bike. This will change co-ordination pattern and you may switch from a nice push pull motuion to a only push down motion. Now to maintain the same wattage you now have to produce this with less inv9lved muscle groups and you may have to activate more motor units on the " down pusher". This will demand a higher ATP production as the ATP is used faster. This again will potebntially shift the slow ATP production over FFA to more ATP ( faster ) production with glucose involvement. This agin will need less O2 ( Thats' why the HR doeas still not drift , but it will prodcue more CO2 , which will increase the respiration rate and the demand of O2 for teh respiratory system. If the O2 dmeand of the harder working respiration sysytem is close or equal to the lesser use of O2 due to shift o from FFA to Glucose, there is no change in cardiac hemodybmaic for a while. The problem now is , that you set a "time bomb " by using more glucose and there is now an energy storgae limitation in case you don't feed. 2. Heart rate drift close to LBP. We see in this situation two trends in heart rate drift fro the moment. a) The SV starts dropping due the different reasons. - heat - dehydration to name to simple to understand once. As SV droppes so woukld as well drop the CO ( cardiac output ) as wee saty on the same performance level ( Wattage ) we have to keep the same CO and if SV droppes we have to adjust with a higher HR. Now here are some interesting observation we had lately. SDome days this works incredible well SV dropes HR is going up and you feel very good. Some days you see the same, but as HR drifts up you start to feel not ghood and in fact you see an increase in lactate accumulation. Now here one observation which made the difference between good and bad feelings. In teh good feeling you see a drop in LVET which than keeps interestingly the CCT ( cardiac contraction time nicely below 30 sec. IOn the bad feeling out of what ever reason the LVET does not drop and the CCT increases slowly to 30 sec and above and you feel not good anymore and you see a trend in increasing lactate. I am not sure , what is provoking in some days a drop in LVET and in otehr days not. . There could be some nutritional elements in there ( Ca++ ???? ) and I will in the next few weeks play arround with this, as for the moment in every traiing I run or bike with the Physio flow to see limitations and new ideas on my own workouts.) I will print in the next few weeks ome of the workouts out here with different intensitty interventions and you can first hand see, that it is not so easy to plan a Stroke voulme i workout , as we can see in some cook book apporaches we showed on the is forum many times. What is very clear any time I work out is the fact , that the previous workouts the one or more days before have a profound impact on hemodynamic reactions, and that any zoning has to be reviewed by developping some easy to handle "bio marker " test to see fast and easy , taht something has changed. Using HR , rspiration rate, SpO2, lactate in combination with performance ( wattage ) is a very easy way to assess, asa long we give our brain a small kick to look further , than just the handle bar and on speed, wattage time and so on. This datas are for us open workout datas. The physiological Bio markers are for us informations on the effect and possible duration of teh hidden workout. So this should give you some sunday evening brain workouts to enjoy . Juerg | ||
| Juerg Senior Member Username: Juerg Post Number: 1818 Registered: 04-2006 |
Here an interesting mail from NOC center Virginia to discuss and review. Heart Rate driftþ From: Douglas Baumgarten (fitnesscc@cs.com) Sent: August 30, 2009 8:53:54 AM Juerg - amazing that I just ran an internet search for "heart rate drift"...and this discussion (http://www.fact-canada.com/discus/messag es/86/1336.html?1218669413) came up first on the search. I was considering this topic (not the first time) after doing a 50-mile road bike ride last Friday. Unfortunately I only have a Garmin heart rate monitor on my bike - and no wattage meter yet - but I found a very interesting phenomenon during the ride. My goal was to increase endurance [training for century], so I was determined to keep a fairly steady pace [work rate] throughout the ride. The course included some hills - and I did push some short intervals - but most of the time I tried to keep my heart rate at a comfortable BI level...for me around 135-150 [keep in mind I have not actually tested myself yet on LBP/zones]. After about 1 hour 30 minutes, my heart rate started to "drift" upward...now 150-165. With only heart rate and speed monitored, it's difficult to be certain, but what I perceived: 1. My work rate/wattage/pace was about the same AFTER 1:30 as it was before. 2. My breathing was the same (quite comfortable except on some hills) throughout. 3. My legs felt good, with no significant fatigue at 1:30, although gradually they felt less "snappy" as I went along. 4. At about 2 hours 45 minutes, my legs significantly fatigued and I had to drop my pace for the last 15 minutes. I'm not sure where the "drift" after 1:30 came from: a. It was a warm day - maybe my body temp rose after 1:30 and blood was shunted to body surface. b. I was sweating heavily, perhaps losing more fluid than I was drinking - maybe dehydration reduced my plasma volume. c. Perhaps my legs were gradually fatiguing, even though I didn't notice at first. What was interesting to me DURING the ride was that I really didn't "feel" the HR drift - systemically I felt just as comfortable at 155-160 HR as I had felt at 140-145 | ||
| Juerg Senior Member Username: Juerg Post Number: 1830 Registered: 04-2006 |
I like to show a very old print out form the start ages of PE 2500 by Polar. It is from the book from Jannsen Lactate and HR. It is a very nice example , who the drop in surface ( body temperature dropped the HR and the speed could be maintained. The reason for this drop is the reaction of the body by having more blood back in the circulatory system ,which increase the EDV and therefor as well the Stroke Volume, which than allowed the HR to drop by maintaining the same CO ( cardiac output ). In the above story it was more likely the opposite situation. The cardiac drift was likely ( but not only ) caused by a drop in available blood volume ( heat and hydration ) which than caused a drop in the EDV and a drop in the SV and therefor , as long the cardiac muscle was able to react ( as he was not or not yet ) at his own limit , an increase in HR ( heart rate drift. In cases where athletes dry to push harder , but the heart rate just simply can't be pushed up we see in some cases studies ( not enough yet ) a change in LVET ( left ventricular ejection time. The time the heart is contracted is going up ms are longer and now the heart rate seems to have to drop due to the CCT ( cardiac contraction time . Perhaps this may be in the future a Bio marker of a " fatigue " of the heart ??? We will see as more people now start to use the physio flow and we can start to exchange more info's. I hope to see soon some very interesting Physio flow info's from Abu Dhabi and Duncan from his NOC Level IV Center. Here the nice print from the race with the rain shower.  | ||
| Juerg Senior Member Username: Juerg Post Number: 1847 Registered: 04-2006 |
Here some more thoughts in the ongoing discussion over HR drift. In FaCT discussion with people using the HR drift as a common point to argue HR as a not very good bio marker for intensity zones, we often start the discussion with : In FaCT workouts we actually have training ideas, where we never will see a heart rate drift. Very often you will see a clear expression in the faces, as :" what a bu.... " Now here the next part of the discussion: If we train with a fixed HR , arguing , that HR is a bio marker for the numbers of beats the heart is doing per minute, and you maintain this HR over 1 or 2 or three hours by adjusting the power out put or speed accordingly you will not see a HR drift at all but you will see a "performance" drift. The performance drift will mostly be in the direction of a slower speed and or a lower wattage. Now assuming . based on traditional believes, that the stroke volume will reach a plateau by about 130 HR ( which can happen but is not always teh case) than if we have a stable SV and a stable HR we have a stable cardiac output and therefor a relative stable performance. Now if we maintain the same HR over time and we loose performance, than something has to go out of balance from the respiration system to the O2 transportation system to the cardiac hemodynamic. The same has to be true to a certain degree as well , if we maintain the same wattage over this time and we see an increase of HR as a cardiac drift. Here starts now the interesting discussion and it may be for many a clear info, , why a "cook book " can't not work that well in any case of training zoning. I like first to show a print out of two 55 year old males. You can see the HR is starting different with one guy a lower HR and a higher Stroke volume, but than soon getting to a plateau with SV and in the end actually even dropping down. The other starting relative lower SV and higher HR and than steady increasing SV till to the end of the test. Interesting is as well the longer LVET by the guy , who started with a lower HR but than later he adjusted to a drop in LVET and if we looked it was perhaps coincidentally or not by a CCT of 30 sec ( HR of 140 +- and LVET 210 + and drop by HR 145 - 150 down below 200. Now here no conclusion based on this comparison but just using it as a reminder, that much of the reaction the body is just doing will not show up as a clear information , if e use wattage or HR only.On the other hand it shows, that we can really start to do some much deeper individual assessing and consulting with patients and athletes , when we have more of the above information. This will lead us back to the VO2 max discussion , where we believe, that there are genetic limitation but in many cases there was perhaps still lot's of room for improvement of one or the other system , but because we only look at the overall picture of max wattage and or Max Hr and max VO2 , we miss the ability to find the weakest link and we blame the limitation in performance of this athlete to his lack of genetic , rather our inability to find the weakest link. If the cardiac system is the weakest link and we push daily that and only that system to its limitation we will not see an improvement but rather a drop in VO2 as the muscles never will be pushed to their limitation due to the CG and the heart limitation. Both did a test to their individual heart intensity  Now back to fixed HR and no shift in performance. Well that may be the easiest speculation : all system are running well and non of the system seem to loose performance so no reason to adjust something. HR stable and drop of performance " Performance drift . There are different reason why performance may drop by maintaining the HR. - SV dropes and with it the CO and the delivery of O2 to the working muscles. This is one of teh reason , that I believe the CO may be the better assessment tool than VO2. Nevertheless VO2 max is CO x (a-v) O2 difference. SV can drop with the same EDV due to drop in Ejection fraction % ( ??? fatigue of cardiac muscle contraction ???) We would see that as a drop in the LVWindex ?? SV can drop due to the drop in the amount of blood moving back to the heart (EDV ) which could be caused due to dehydration and or heat , Opening of surface blood vessels. Performance could drop despite a fixed HR due to an increase in the left ventricular ejection time. If the intensity is close to the LBP and increase in LVET may cause an increase in CCT ( cardiac contraction time, which means that the heart muscle itself is longer contracted and therefor is getting less O2 for its own work , which can kick in the CG ( Noakes ) and therefor reduce muscle unit recruitment, which means less units have to try to do the same work , but simply can't and performance will drop. So many and possibly more reason for a performance drift. Now performance stable and a drift of HR. Well same ideas as before. SV will drop but to maintain the same CO the HR has to go up. Or LVET dropes so the HR can actually go up and ,any more ideas you can try by now to get the different combination together. If we are able to assess and understand the drift in HR and or performance , we will be able to much better plan and understand the bodies respond to the different trainings we try to use to stimulate performance improvement. To give you some "home work " I like to use from the same BOOK from Jannsen a very nice example of a "negative HR drift " where the athlete just simply could not maintain the HR at all and it drop steady during the race. Try to produce different scenarios on the above ideas, what may have happened during this race and why the HR may have dropped. here the print :  Now you can see an "end-sprint " HR spike. This is where "anti CG believers will come and argue, that it shows the CG can't work , as there would be no way he could have made this end-sprint, as the CG is controlling his output. I would argue exactly the opposite. This end-sprint proofs that the CG was protecting the heart over the whole race. The control of the CG allowed the athlete to race in the O2 dependent intensity and gave him the chance to keep the ATP storage full so that at the end he had a chance to actually push a short moment in the O2 independent intensity , where he does not need O2 and the heart did not mind for this short moment , as it was not in trouble over its own pO2. If the end sprint would have gone longer the CG would have picked in and the athlete would slow down before the finish line. There is only so long you can go all out and than the fire is out. It needs either years of racing to get the experience for that moment ( how long you can go that fast ) or a very smart athlete with a very very good "apprenticeship " and a good mentor to understand this physiologically and use it in a race. The best example for me ever was the triathlon in Beijing and the Canadian Whitfield , who either had that incredibell feeling or all of the above knowledge so as they pushed very early on to and end sprint he just knew : Either they are so much better on with their ATP situation and they are simple gone, or they are too exited and will have no chance to pull that throu . If latter is the case I will pick them up again and they will switch at that moment from the reptilian brain to the human brain seeing their medal disappearing , which needs "more O2 " and I will simply digging and keep running on my reptilian brain and don't care for the moment anymore. . Nice theories but may fit together much better than the idea of lactic acid and fatigue and or any VO2 max limitations. Summary : I believe that over the next few year coaches who are ready to make the next step forward will make a huge gap between the mainstream cook book coach and their incredible ability with all this equipment to bring out the very individual best in each of their clients. This combined with the genetics they may have will allow many more athletes to reach the top , they never would have been able as they get stuck in a cook book approach. |