Alias530

1.) Why is it that towards the end of a longer ride, my heart rate is higher at a given perceived effort? When I start out it's obviously low, but once I'm warmed up I will hover around 130-140 on flat ground for moderate effort. At the end of the ride, I'm going 2mph slower and I'm 140-150. Am I dehydrated? Not enough to eat? Or is that just how the human body works?

2.) When I'm riding and I stop, my heart rate will get down to about 100 (from 140) in 30 seconds or less, but it sits at that level for 15+ minutes. I have never stopped that long mid ride before but had to last week and noticed I was still around 100 after 15 minutes of doing nothing. Is this normal to not drop any further beyond the first 30 seconds of stopping? My resting heart rate is in the low 50s.

3.) If I'm around 150-160 when climbing, should I be able to push at a level on the flats that produces this heart rate? I seem way more winded at that level on the flats than the climbs. Climbing is misery, but a different kind.

Thanks in advance, I couldn't find anything about this by searching.

rpenmanparker 

I see the same thing regarding higher heart rate at the same effort later in the ride or indoor training session. I think that is normal. Can't say exactly why.

Alias530

It doesn't happen to me until 3+ hours into the ride

harolddelaney

Dude, I'm no help here but I've had these same concerns. Maybe I'm way off, but heart rate monitoring seems kinda worthless, so unpredictable and can be affected by many different things. Perceived effort FTW. Don't even bother with heart rates anymore.

spdracr39

When you get tired you engage more muscles to cover for those that aren't able to do the work on their own anymore. This draws more oxygen from the blood and the heart has to beat faster to accommodate the added demand. Your posture also starts to change which decreases efficiency and again helps to deplete oxygen supplies faster. Nutrition and hydration are also factors but your heart rate is mainly about supplying oxygen to the muscles, reoxygenating the blood in the lungs, and removing CO2.

txags92

For your first question, I would suspect that as you get later into long rides, you have exhausted your glycogen stores and your heart is working harder to provide energy through other pathways. For your second, even if you aren't working hard anymore, your body still has processes it is trying to feed in the muscles that were just working, so your heart rate will stay up to provide that blood flow. For the 3rd question, is your cadence the same for both efforts? My experience is that when my heart rate is up under a heavy climbing load at slower cadence, it isn't as painful as being at the same heart rate with lighter resistance at a higher cadence. No idea why that is, but I definitely notice it.

I tend to have the opposite of your first problem late in very long rides. I reach a point where my HR just won't get to the levels I had it earlier in the ride. The fatigue in my leg muscles just makes it impossible to pedal at a speed that would get my HR above about 80%. I assume it has something to do with lactic acid buildup, but who knows for sure. I tend to think of it as my body's natural governor telling me I have done enough and I back off and ease up for the rest of the ride.

caloso

Cardiac drift.

Alias530

I usually at 1 hour and every 30-45 mins afterwards on rides I know will exceed 2 hours. If my ride will be 2 hours or less, I won't eat at all. For example... yesterday was a 65 mile ride. I ate at 20 miles, 30 miles, 40 miles, and 55 miles (a banana or a gel each time). I wouldn't think my glycogen levels would be depleted...

My cadence is lower when climbing. There are roads around here where I can barely hold 50rpm on the way up, but I'm usually 88-92 on the flats. However, if I were to sprint to speeds that would get my heart rate into the levels they reach when climbing, I'd just be in a higher gear at the same cadence, but my heart rate would be way higher. I just feel like 8mph on a climb puts me at the same heart rate as 30mph on the flats (rough estimate), but I can't hold 30mph on the flats nearly as long.

txags92

What are you eating before you ride, if anything? If you are expending 400-600 calories per hour and only consuming 100-200 (a banana or a gel), you are not replenishing what you are using. I was thinking of 3+ hour rides when I was talking about longer rides. You are unlikely to be in a depleted state on a 2 hour ride unless you are just thrashing yourself or started out not fully fueled. If you are seeing it in shorter rides, I would lean towards Caloso's cardiac drift explanation.

Alias530

Yesterday--

6am -- 1 cup oatmeal, protein shake, handful of raspberries, greek yogurt
9am -- 1 cup dried mangos
12pm -- big salad (lettuce/olive oil/balsamic), 2 home made burritos (tortillas filled with chicken and black beans)
2pm -- start ride

Carbonfiberboy 

You're just not in shape. Ride more, especially long moderate rides. It's probably just HR drift. It can also be dehydration, which will significantly raise HR for the same RPE. It's not nutrition. Too little nutrition depresses HR for the same RPE, just the opposite of what you are experiencing.

rpenmanparker 

I don't think that's right. This is a fairly widespread phenomenon. Of course "in shape" means different things to different people, but I am pretty fit and see the effect over the course of a half hour on the trainer.

Alias530

I can't say I agree with that... I average 8-10 hours a week of cycling (maybe 7-8 during winter) and do 2-3 days of weights and hiking a few times a month too. Obviously it's a relative statement, but I'm not some fat slob who is new to exercise by any stretch of interpretation.

Carbonfiberboy 

Yes it is widespread, which doesn't mean I'm wrong. If you're experiencing drift in a half hour on the trainer, you're just seeing the normal HR coming up during a warmup. Riding z2 on the trainer, you shouldn't see drift between 1/2 hour and 1 hour. When I'm in shape, I don't see drift over 1/2 hour of a z3 interval.

Carbonfiberboy 

Who said you were a fat slob? You could try training a little differently. Maybe a little late for this, but back-to-back hilly weekend rides of 3-4 hours each, staying in zone 2 the whole way, including climbs, will make a difference.

As I said, it could also be dehydration.

If you can't get your HR up on the flats, it could be posture. People tend to get more aero on the flats, which can close the chest. Try going hard on the flat using your climbing posture, see if there's a difference. Try rotating your pelvis forward and straightening your back. Or something odd about your fit or pedaling. Or maybe just practice. Try doing 15' LT intervals on the flat. It should actually be easier to get your HR up at high cadence. Try 100.

When my HR doesn't drop below 100 during a break, it means I'm cooked. I've been going way too hard for my current conditioning and for just a training ride.

Alias530

If it's drift, I don't see it until 3+ hours into a ride. I see the higher-than-normal resting rate pretty quick though, but I rarely stop more than a minute or two at a time while I'm riding.

popeye

Google "aerobic decoupling" as well as cardiac drift. It is an indication of your fitness.

Alias530

I guess that's just not what "not in shape" means to me. There's a huge range of "in shape" but if I were to call someone out of shape, it would be because they were fat and rarely if ever exercised, not because they were in WAY above average fitness but their heart rate drifted 10 points after 3 hours of hard exercise. I guess that's nitpicking... anyway, back on topic

The only times I even break 150 beats is climbing or sprinting at a level I can't maintain for more than 30 seconds. I don't think I've even seen my heart rate ever go above 165, even when setting KOMs out of 5,000+ people on sprint segments where I need to stop for a full minute or more to recover after just 30-45 seconds of sprinting. I've heard that people from a weightlifting background (like myself) typically have a lower heart rate for a given exertion level.

Carbonfiberboy 

Well, you're a heckuva good sprinter! You just have to decide whether the aerobic training necessary to get your HR to do whatever is worth it to you, since it will probably hurt your sprint.

bikepro

It's caused by "cardiac drift". There are numerous articles on the WEB.

RollCNY

OP, are you really 6'6" tall and 250lbs? You mention these numbers in a different thread. If you are a weight lifter build and are now cycling, your aerobic system may be your week link, and you may be performing well in sprints due solely to strength.

Cardiac drift sounds like the right answer, and I was about to post the same thing before CFB did. You saying it happens after hours of moderate intensity effort fits fine with drift, since it is about loss of pumping efficiency over time.

But your numbers seem really weird, with a resting heart rate of an experienced endurance athlete, and the max heart rate of a geriatric prison guard. The stuff about dropping to 100 in 30 seconds and then hovering there is strange. When you do interval workouts, does your HR drop that fast and plateau? Maybe my HR is slow to drop, but I don't recall losing 30-40 BPM even in a minute rest period.

And as to pushing harder on hills, that might be easier to explain if you are 250 lbs, with much of it upper body. Gravity makes the work harder, you push harder than your body weight on the pedals, you let your cadence drop, you recruit your upper body, and your power and HR climb. The hill is defined length, you push through the distance at higher force, and you're there. On flat ground, if you want to push harder, usually your cadence is higher, you aren't braced and pulling with your upper body like you are on a hill, and there is no end in sight, so it feels limitless. It becomes mentally harder to push that fast, so most don't.

TANC

Exactly. The more tired you are, the higher your heart rate will be to produce the same effort. In other words, at 300 watts early in a ride, my heart rate may be 140. Later in the ride, 300 watts may be 150 heart rate.