Some of my handy references tell me that an untrained individual will experience LT at 55% of VO2max while a highly trained individual will not reach LT until 80%-90% of VO2max.
If an untrained or lightly trained individual consistently performs an effective endurance exercise program in a given mode of exercise, say running, would that individual’s HR at LT increase as the intensity required to reach LT increases from ~55% and approaches 80%-90%?
There are some internet articles out there that suggest that HR would increase in the above scenario. The only study that my Google-fu managed to pop up on pub med, http://www.ncbi.nlm.nih.gov/pubmed/10211855, contradicts those articles and says, “These data suggest that although power output at AerT, AnT, and maximal exercise changes significantly with conditioning, there is no systematic change in the associated values for HR and/or RPE used as practical markers of training intensity. Accordingly, a single well-conducted evaluation may allow evaluation of appropriate training markers that may be longitudinally stable.”
Granted, this study involved athletes that were probably at least moderately trained, though deconditioned, and were not tested in the same mode of exercise in which they trained/competed so it may not be the most appropriate to answer my question, above. Appreciate your insight.
Let me see if I can get what you are trying to lay down. When an untrained person trains at to get their lactate threshold to the point where they can maintain 80% vo2 before reaching LT, shouldn’t their HR’s increase? Maybe I am confused but there is a difference between your bodies ability to produce and then clear lactate, and heart rate. Heart rate does, however, show a linear relationship with vo2. LT is the bodies maximal amount of lactate your body can handle. It’s also about training the energy system. an untrained person reaches LT at 55% because they have to rely a great deal more on fast systems like glycolysis. A trained endurance athlete can more effectively use slower energy systems like fat oxidation and thus prevent a huge buildup of lactate (without having the means to convert it back to pyruvate).
Let me see if I can get what you are trying to lay down. When an untrained person trains at to get their lactate threshold to the point where they can maintain 80% vo2 before reaching LT, shouldn’t their HR’s increase? Maybe I am confused but there is a difference between your bodies ability to produce and then clear lactate, and heart rate.
Yes there is a difference between LT and HR, however if an untrained person begins training with HR, his/her tempo run/threshold training zone will occur at or near a HR where the body is at 55% of VO2max (LT). As this person becomes more trained, he/she does not reach LT until achieving 80%-90% OF VO2max.
Since Heart rate does, however, show a linear relationship with vo2. would the person’s HR at LT (where he/she should be training to improve LT - tempo pace) increase as he/she moves from untrained to highly trained?
It seems to me that this would be the case since HR at 90% of VO2max should? be greater than HR at 55% of VO2max. The study I linked to in the OP appears to indicate that this is not the case and that HR at LT remains constant as fitness increases.
would the person’s HR at LT (where he/she should be training to improve LT - tempo pace) increase as he/she moves from untrained to highly trained?
The LT curve moves to the right, the actual HR number might not change with the shift. t
HR at 90% of Vo2 max should be higher then at 55% of vo2 max.
A long time ago (8-10 years) I trained by HR only. Based on training/testing back then, my HR at FTP was 169-172.
A couple years back in the sport, and I’ve been training with power. I still check out heart rate after workouts, since a trend of increased power at a given heart rate has been a predictable indicator of better fitness for me.
In the off season, with a lower FTP, my 2x20 intervals at 1 hour power elicit a HR around 172 and a power around 280.
Closer to the season, with a higher FTP, my 2x20 intervals at a 1 hour power elicit a HR around 172 and a power of 300-320.
Stroke volume probably has a role in this- if you are getting more blood per beat, then your VO2 is ^ and your HR is <->.
-Physiojoe
So one vote for no change and one for increase - got it.
Mine comes down for a given power.
Now that I am in a much better state, I should be able to help you with your question.
When training, you are looking to both increase your bodies LT and you are trying to become more efficient at utilizing oxygen and energy systems to work for long durations at high intensities. When your LT reaches the point to about 90%, and everything else is balanced in your training (food, etc.) then you should be able to hover just below that LT for longer periods of time. Your heart will still be pumping at a faster rate at 90% VO2 then it was at 50 VO2 trained or untrained. The difference in the trained person is that your heart will be pumping a bit slower because your body is more efficient. Your capillaries are denser, your mitochondria count in slowtwitch fibers are higher and your mitochondria have gotten bigger. So whereas your body untrained would be at say 150bpm @ 50% vo2 and 187bpm @ 90%, training might make is so you can stay at the 90% vo2 but at 175bpm, but it would be unlikely that you can be at 90% vo2 (new LT) and still only be at 150 bpm.
Mine comes down for a given power
mine too, but that is expected as a result of increased sv.
Some of my handy references tell me that an untrained individual will experience LT at 55% of VO2max while a highly trained individual will not reach LT until 80%-90% of VO2max.
If an untrained or lightly trained individual consistently performs an effective endurance exercise program in a given mode of exercise, say running, would that individual’s HR at LT increase as the intensity required to reach LT increases from ~55% and approaches 80%-90%?
If I understand your question:
Given the HR for an unconditioned person at 55% of VO2max
Does HR of the same person, now conditioned, at 80%-90% of VO2max, increase to a higher number?
I am presuming as the heart itself is trained with improved capillary and mitochondria density, it would be able to perform at a higher HR for a longer time, offset by stroke volume gains.
I am curious to see what the real exercise physiologists have to say about this.
I am curious to see what the real exercise physiologists have to say about this.
me too. was hoping dr coggan or skiba might chime in.
The threshold HR generally does not change that much if at all, but the pace or power at the HR does with training.
OR another way to look at it
For the same pace/power the heart rate and/or RPE will be lower than it was pre training.
Now to contradict that alittle, there is some interesting info that has indicated an increase in HR over a period of specific interval training in running (not sure on the other sports). However, I’m not sure this indicates an increase in the threshold HR as the intervals were much shorter.
Don’t discount desert dude’s response.