bikebrat

Thinking this might get lost at the end of the Aerobic Threshold thread, I'm posting this again as a new thread . . . Sorry for doubling up like that.

Koffee - It's great to hear from someone who clearly has an in-depth understanding of heart rate, aerobic and anaerobic threshold, etc. - since I have a few questions! (And, anyone else who is knowledgable on this subject, please feel free to chime in!)

First, in the absence of laboratory testing, I've used a calculation that I'm not sure I saw referenced in this thread, that - based on how I "feel" at various heart rates - I think comes a lot closer than the 220 minus age. - It starts with 220 minus age, but then subtracts resting heart rate. You then apply the percentage you want to work at, and then add your resting heart rate to the product. At age 48,with a resting heart rate of 45, this formula gives me 140 for 75%, compared to 129 based on 220 minus age, or 153 for 85% as opposed to 146. - Does this make some sense?

Okay, that's my calculation question . . . Now, to the "practical applications" questions . . . Since this winter has been so bitterly cold and snowy/icy compared to last winter, I have spent a lot more time in the gym - spinning, treadmill and weights - and paying more attention to my heart rate monitor, and would love to understand a few of the things I am discovering. So, if you can help, would love your answers to the following:

1) When doing a spinning class interval ride, during a hard effort, my heart rate will hit between 155 and 160 for the 30 to 60 seconds that we are sprinting, or whatever . . . and by the end of the effort, I am either breathless, or my legs feel like they couldn't sustain the speed (or resistance, as the case my be) a second longer - or, more often than not, both! - And yet, when we do an endurance ride, I have found that my heart rate just gradually increases, and after 30 minutes or so, I'm feeling so good in the mid-140s that I increase my speed or resistance, and move easily to 155, and am able to sustain that rate for much longer - AND, it doesn't "feel" anywhere near as difficult as that same rate feels during an interval ride. - Is this typical? Why is this? And what should it mean for my training?
2) There are some days (usually after several days in a row of intense training, including strength work) when my legs get in the way - i.e., my legs just can't take the necessary resistance and/or speed to get my heart rate up over, say 65%. One of the spin instructors keeps trying to tell me it's lack of oxygen, but that makes no sense to me . . . since I'm not having any trouble breathing and my heart rate is staying relatively low - my legs are just sore or fatigued. Am I right in thinking that there are times when your muscles can not keep up with what your body is capable of aerobically?
3) Finally, before I do weights, I spend 10 to 15 minutes on the treadmill and get my heart rate up to about 65% to 75%, just to warm up. But, during the actual weight lifting, my rate generally stays below 50% - sometimes WAY below. - Is this typical for weight training? (I am generally doing 3 sets of 15 to 20 reps, and the weight I use brings me to near failure at the end of the 3rd set.) Does this mean I am not burning any fat when doing weights? Does it matter? I mean, am I still building muscle?

Thanks . . . I look forward to your answers.

Guest

Hi Bikebrat-

I've just been a little busy lately. Let me take a look at your question and I'll respond sometime tonight over coffee....

Koffee

lotek 

Bikebrat,

While Koffee is pondering over coffee (I couldn't resist)
I'd HIGHLY suggest getting Sally Edwards
The Heart Rate Monitor Book for Cyclists.
I believe that she answers many, if not all, of the
questions your asking.
I'm just getting into the entire program, and to tell
you the truth, even after years of riding, I realize I
never had a good program, nor a valid way of measuring
gains in fitness etc.
This book does it all. . .
(uh, I guess you could say I'm impressed with it).

Marty

Guest

Lotek-

That book- "The Heart Rate Monitor Book for Outdoor and Indoor Cyclists", by Sally Edwards and Sally Reed is an excellent book for people looking for a solid training program. I highly recommend that book for anyone looking for direction with their training.First, in the absence of laboratory testing, I've used a calculation that I'm not sure I saw referenced in this thread, that - based on how I "feel" at various heart rates - I think comes a lot closer than the 220 minus age. - It starts with 220 minus age, but then subtracts resting heart rate. You then apply the percentage you want to work at, and then add your resting heart rate to the product. At age 48,with a resting heart rate of 45, this formula gives me 140 for 75%, compared to 129 based on 220 minus age, or 153 for 85% as opposed to 146. - Does this make some sense?

Bikebrat- Let me break up your questions and attempt to answer them as best as possible.
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Question-
1) When doing a spinning class interval ride, during a hard effort, my heart rate will hit between 155 and 160 for the 30 to 60 seconds that we are sprinting, or whatever . . . and by the end of the effort, I am either breathless, or my legs feel like they couldn't sustain the speed (or resistance, as the case my be) a second longer - or, more often than not, both! - And yet, when we do an endurance ride, I have found that my heart rate just gradually increases, and after 30 minutes or so, I'm feeling so good in the mid-140s that I increase my speed or resistance, and move easily to 155, and am able to sustain that rate for much longer - AND, it doesn't "feel" anywhere near as difficult as that same rate feels during an interval ride. - Is this typical? Why is this? And what should it mean for my training?

ANSWER:
First, what is your recovery time when you're doing your interval rides? Are you getting enough rest time in your interval? Typically, for anaerobic efforts, you want to give at least a 1:1 ratio for work to rest. So, if your work effort is for 30 seconds, your recovery is also 30 seconds. I actually prefer the 2:1 effort given by Ed Burke (Serious Cyclist), where (ie) your work effort is 30 sec, so your recovery is 1 min. This allows you to convert the lactate back to pyruvate in the body and bring in enough oxygen so that your body can begin using the aerobic pathways again to build up ATP stores so that you have more energy to do more intervals. Often, I observe a lot of the spinning classes, and I see instructors doing intervals that I wouldn't ask a professional athlete to do. Most often, it's because they truly don't understand the objective of the interval class. A couple of days ago, I looked up training rides for Lance Armstrong, and I found an example for my class so they could put their interval classes into perspective:

Lance's Olympic Time Trial Warm-up Schedule:
Am: 1 hours easy road ride, keeping rpm's high, 95-100
Pm: Warm up begins on an indoor trainer
15 minutes @ 120-140 heart rate, rpm's 90-95
5 minutes @ 140-150 heart rate, rpm's lower, 65-70
90 seconds @ 175-180 heart rate, rpm's high, 95-100
5 minutes @ 120-140 heart rate, rpm's 90-95
90 seconds @ 175-180 heart rate, rpm's high, 95-100
5 minutes @ 120-140 heart rate, rpm's 90-95
90 seconds @ 175-180 heart rate, rpm's high, 95-100
15 minutes @ 120-140 heart rate, rpm's 90-95

For the high intensity efforts he does, his recovery efforts are sensible. So I asked them if they really needed to do everything at 90% efforts for minutes on end with very little recovery time. People actually looked confused- no one ever took the time to talk to them about interval efforts, and I ended up putting together a guidebook and passing it out to class. It worked. Today we did intervals, and we had no problems in class with working high efforts for short time periods with a 1:1 effort for some parts, and a 2:1 effort for the parts that required higher intensity efforts.

Anyway, just get an idea of what the ratio of work to recovery is by your instructor and let me know what they say, and then we can revisit your question again.

Having said that, I was interested in your question about endurance heart rates vs. interval heart rates. I assume when you are doing your interval classes, you are pushing high heart rates for the work effort, followed by a brief recovery effort. I believe that typically, the interval classes given by instructors do not allow for enough recovery time for the participant to recover sufficiently for the next work effort. As a result, the amount of lactate in the blood rises quickly, and accumulates much faster than in an endurance class. As a result of the rapidly rising lactate levels, the participant finds it difficult to maintain the high intensity interval class. Each anaerobic effort decreases the amount of oxygen the body receives for the efforts it performs. This brings on the oxygen debt, which results in an increase of lactate in the bloodstream. With a rise in the lactate levels, the body is unable to rebuild ATP levels because the body uses carbohydrates as it's primary fuel source- coming from glucose stores. With the metabolism of the glucose through anaerobic pathways, the end result is less ATP, so less energy is produced, which means the body gets tired. Until you slow down sufficiently enough to bring in oxygen to utilize the conversion of lactate back to pyruvate to drive aerobic pathways, thereby increasing ATP levels so that the body has more energy to do the work, you will bonk. That's why it is so important to time your recovery when you are doing the higher intensity interval class. Not enough recovery= less energy to do the work effort, so higher heart rates are unattainable. You will bonk early and soon into the class.

On the other hand, when you do endurance classes, the buildup of lactate is slower. An endurance class is an aerobic effort where you train the cardiovascular system to work efficiently by utilizing more oxygen, and also train slow twitch fibers (with mainly oxidative capacity and lots of mitochondria) to react more like fast twitch fibers- which makes you faster and stronger. Also, the endurance class allows you to work on things like cadence, resistence loading, etc.... it has it's benefits.

With a slower buildup of lactate, you can adapt to the workload. This is part of the training experience. As you adapt, you will (hopefully) work with your heart rate monitor to build up speed or resistance, while keeping heart rate within a reasonable range. Even as you increase the workload slowly, over time (and I'm talking time like months and years), you will see those benefits I mentioned in the earlier paragraph. Your body will be able to tolerate the rising levels of lactate, because the amount of oxygen entering the body is sufficient for the lactate to convert to pyruvate, which drives the aerobic respiration process. So what's going on? I suspect in your case, 155- 160 heart rate may be closer to your anaerobic threshold, or just under your anaerobic threshold. If you find that you warm up sufficiently (for a higher intensity interval workout, try 10 minutes), followed by a conservative set of intervals, before going into higher intensity intervals, you probably could do more for longer, and maybe even at higher heart rates. I find it hard to say for sure what's going on in your case since I don't monitor your workouts. But try it and check back and let me know what's going on with you.
______________________________________________________

Question-
2) There are some days (usually after several days in a row of intense training, including strength work) when my legs get in the way - i.e., my legs just can't take the necessary resistance and/or speed to get my heart rate up over, say 65%. One of the spin instructors keeps trying to tell me it's lack of oxygen, but that makes no sense to me . . . since I'm not having any trouble breathing and my heart rate is staying relatively low - my legs are just sore or fatigued. Am I right in thinking that there are times when your muscles can not keep up with what your body is capable of aerobically?

ANSWER:
There are just some days when your body is too tired to do the effort. There are a lot of factors that can affect heart rate, and on those days, I advise my participants to put their monitors away and go by rate of perceived exertion- listen to their bodies and let their bodies dictate what effort they will give in class. There are times when your muscles cannot keep up with what your body is capable of. There are also times when your heart is just over-fatigued.... all typical signs of overtraining (although there could be other problems, like lack of proper nutrition, altitude if you are training at sea level, then travel to a place at a higher altitude, if you are becoming sick, not enough water during class, etc...). For instance, I was cycling at least 2 hours a day on weekdays, plus teaching 6 classes a week. On the weekends, I'd do a 4- 5 hour ride on Saturdays, and a 3- 4 hour ride on Sundays. By the end of the summer, I was beat. I saw my heart rate was plummeting, no matter what I was doing. Typical Koffee, I disregarded what I knew and figured I was probably being lazy, so I worked on increasing my cadence. For about a week, I was killing myself before I figured out something was wrong. So I took some time off, and within a day of when I decided to take some time off riding, I had the flu- my heart rate was actually telling me that I was in the beginning stages of being sick. I was sick for a little more than 2 weeks, and I took about a month off, and when I came back, I found my heart rate ranges back to normal. Listen to your body when you are working out and don't be a slave to the monitor. If you don't see the numbers you typically see, do an evaluation to determine what the problem is. If you're not getting better, take the time off. Some variables can be adjusted within a short time frame, but when you're sick, or you're at a different altitude, there's nothing you can do but train based on rate of perceived exertion.
_____________________________________________________

Question-
3) Finally, before I do weights, I spend 10 to 15 minutes on the treadmill and get my heart rate up to about 65% to 75%, just to warm up. But, during the actual weight lifting, my rate generally stays below 50% - sometimes WAY below. - Is this typical for weight training? (I am generally doing 3 sets of 15 to 20 reps, and the weight I use brings me to near failure at the end of the 3rd set.) Does this mean I am not burning any fat when doing weights? Does it matter? I mean, am I still building muscle?

ANSWER:
Weight training is not an aerobic workout designed to work the cardiovascular system. Weight training is an anaerobic workout for short bursts of energy designed to fatigue the muscles. (I am pleased to see, first of all, that you are doing a quick warm up to get the muscles properly warmed and stretched before doing weights.) You are definitely burning fat because you are doing weights- muscle requires more energy to maintain the body than neglecting resistence training altogether and focussing on cardiovascular fitness alone. And studies I read suggest that weightlifting will spike your metabolism for the 12- 24 hour period following the session, while cardiovascular training (aerobics classes, running, cycling, etc) will spike your metabolism for 2- 6 hours after completion of the activity. Not to say you shouldn't do cardio- the best results are achieved by a combination of cardio AND weightlifting, among other things like nutrition and diet, rest days, etc. Over time, as long as the stress achieved from weightlifting continues, you will build muscle. BUT if you don't work to increase your weights when your muscles adapt to the workload, you will not build any additional muscle. You are just maintaining the muscle you have. So if you're working to build up the muscle mass, keep working to increase your weights. As muscle mass increases, your metabolism will continue to rise, as the additional muscle will require additional energy (fat), which will result in fat loss, which means you will slim down.

I know you could tell from my other post that I am not a big fan of estimated heart rate, even if the formulas are more precise than 220 minus age. I stress that some kind of benchmark is needed, BUT the best way you can determine heart rate is through a training lab, and if you do not have access to the training lab, a self test, preferably administered in the presence of a second, neurtral individual who can coach you through the test and monitor the variables would be best. If you can't get even that, then something is better than nothing- a formula will do. Let me give you an example from your heart rate ranges you gave at the beginning of your questions. You said the estimated heart rate based on a resting heart rate subtracted from the 220- age, which is the karvonen formula. This gave a 75% of 140. According to my performance based heart rate chart, that would put your anaerobic threshold (80%) at roughly 150. That puts your 85% at about 160. If this is so, the numbers you reach in your endurance class would not be possible. If I had a student with your numbers: 155- 160 with hard effort, not a lot of heavier breathing, and feeling quite comfortable with maintaining that heart rate over the duration of the class, I would estimate they were working somewhere just under their anaerobic threshold. Furthermore, I would put them through the test and see exactly at what point did you reach the anaerobic levels on their heart rate monitor using the test I typed out in the other post.

I think you're asking some good questions here- I had to take some time to think about this post before I wrote it... it's been a little while since I answered questions like this so extensively. Thanks.

Good luck and feel free to send a PM if you want to ask any additional questions.

Koffee Brown

Joe Gardner

Wow, can i vote that for post of the year? Thanks for the great information Koffee

Guest

As sleep deprived and tired that I am after writing that post, which comes after a 5 hour chat online with a friend, I feel real good after getting your comment. Thanks for a nice comment at the end of a marathon day!

Koffee

bikebrat

I second Joe's sentiment . . . and thank you for such a thoughtful and detailed response. Now I have to spend a little time over a cup of coffee reading your post a few times to make sure I get it all. Your comments on recovery between intervals definitely gives me something to pay attention to in my spinning class tonight. (It's one degree below zero as I write this . . . Will it ever warm up enough to ride outside again??? ) -- Also, I guess I didn't realize that your body could actually adjust to levels of lactic acid, and more easily if you gradually increase those levels over an endurance ride. But what you say makes so much sense to me . . . Again, thanks, and I will keep you posted (and likely ask more questions) as I further digest your post. -- Also, must order the Sally Edwards book you are all recommending!

Pat

First comment. The 220-age is approximate. I have a friend who has gotten up to 210 at age 48. At age 50, I can almost hit 200. I can sustain 165 for quite some time. Things start to hurt over 170 (which might be getting close to my anaerobic threshold).

Question 1) Heart rate lags effort. If you jump up from sleeping and start to run - you will go anaerobic because your heart is still at rest pace. It takes about 5 minutes at a given effort (rule of thumb) for your heart to catch up. I have noticed on quite a few programmed exercise cycles they have very very short durations for effort and wide changes in exertion. Often the changes are too wide for your heart to really "catch up". I suspect that you just need to accelerate a little slower.

Question 2) You are right, your heart should be able to deliver the same amount of blood (oxygen) to your legs from day to day. So that is not the problem. What is probably the case is after a hard day you either are not motivated (which I doubt) or your legs are a bit beaten up and need recovery (repair). If my legs don't respond, I just ride "easy" and they come back in a day or so.

Question 3) Heart rate is dependent on demand for blood supply. The bigger the muscle mass exercising, the bigger the demand for blood and the higher the heart rate. This is why cross country skiing is easier to get an intense workout than cycling because you use arms and legs (more muscle mass). Think about this, could you work your heart hard enough by working on grips with your hands? Your hands are driven by the muscles in your forearms and unless you are Popeye, those are not really big. Another thing about weight lifting is most lifters lift and then relax for a bit so even if they are doing squats (large muscles) - they are not doing that many in any given unit time - nothing like the 100 rpm that a cyclist will crank out so their heart rates should not get that high. Generally, when I lift, like you, my heart rate does not elevate much at all.

nathank

as has been already said, HR when weight lifting depends on which muscles are invloved as well as how many reps and how much break you do...

"during the actual weight lifting, my rate generally stays below 50% - sometimes WAY below. - Is this typical for weight training? (I am generally doing 3 sets of 15 to 20 reps, and the weight I use brings me to near failure at the end of the 3rd set.) "

well, i haven't worn my HR monitor while weight training in a while, but mine is _definitely_ higher than 50% --- i used to wear my HR monitor and use 105 as my "recovery" HR to start another set. i think when i do bench (10 set) my HR is about 135 or so and for lunges in the 145 range (my max is 194, LT 165)

"Does this mean I am not burning any fat when doing weights?"
with weight training you probably will burn very little fat while training, BUT b/c you caloric requirements will go up for weeks to follow first to rebuild the muscle, then to maintain the enlarged muscle mass, you will probably end up burning fat (simply because your body will burn more calories for weeks afterwards)