heart rate curious

tspear

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Timothy
As I get back into exercise, I know my heart rate lags when I start working out. And then stays elevated longer after the workout ends. The second part makes sense to me.

But not the first, it would seem that if you are out of shape and start to exercise, your heart rate should spike really fast. However the actual behavior is reversed.

So my question is, why does heart rate lag so much when you are out of shape?

Tim
 
Do you use a chest strap? Try wetting it before you start your workout. My HR monitor works well when I have a good sweat going. I don't always trust early readings.

Assuming constant exertion, I would expect a spike of your HR at the start of your work out and then a settling down. For me when running, this spike then settle down period takes about 7 minutes.
 
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I don't always trust early readings.

Assuming constant exertion, I would expect a spike of your HR at the start of your work and then a settling down. For me when running, this spike then settle down period takes about 7 minutes.


I too sometimes see early readings that are obviously bad. I use a Fitbit. It helps if I tighten it a little before I start.
 
So my question is, why does heart rate lag so much when you are out of shape?
IIRC, from Covert Bailey's Fit or Fat from the '80s, it's the difference between aerobic and anaerobic exercise? Your heart pumps oxygen to your muscles, but they don't need it right away to function (think 50-yard dash). Longer runs start to demand more oxygen and kick the heart to beat faster (think marathon). Don't think "out of shape" is causing a longer lag.
 
@MICHAEL MAHN

Both chest and wrist follow the same pattern. Yes, the chest strap I moisten before use. The wrist uses LEDs, so actually loses accuracy as you workout and sweat interferes.

@dtuuri

I am just talking about the response rate. I have read in multiple places that the more fit you are, the faster your heart responds. When I search the net for answers; I get things like this: http://www.fmfranco.com/Text/ap_biology/Heartrate and Fitness Lab 2019.pdf
Which is from a bio class, when you look at steps 9-11 you see the expected heart changes for just standing up.

So I am just curious, why it is that way.

Tim
 
@MICHAEL MAHN

Both chest and wrist follow the same pattern. Yes, the chest strap I moisten before use. The wrist uses LEDs, so actually loses accuracy as you workout and sweat interferes.

@dtuuri

I am just talking about the response rate. I have read in multiple places that the more fit you are, the faster your heart responds. When I search the net for answers; I get things like this: http://www.fmfranco.com/Text/ap_biology/Heartrate and Fitness Lab 2019.pdf
Which is from a bio class, when you look at steps 9-11 you see the expected heart changes for just standing up.

So I am just curious, why it is that way.

Tim

I wouldn't put too much into how long it takes for your heart to speed up, the real test of fitness is how fast it slows back down IMO. When I'm in biking shape, I notice it comes down pretty quickly when the hard exertion stops. When I'm in the shape I am now, it takes longer to recover.
 
I wouldn't put too much into how long it takes for your heart to speed up, the real test of fitness is how fast it slows back down IMO. When I'm in biking shape, I notice it comes down pretty quickly when the hard exertion stops.

This ^^

If you are a runner, for example, this is why you want to do sprint training and fartleks ... You're training your heart to recover from strenuous exertion which in turn creates a stronger heart and improved aerobics capacity.
 
I took a little over a year off from the gym when Covid hit in 2020 didn't get back in there till June 2021 it was tough getting going again. Sweating, heart racing, just feeling lousy for about 3 weeks I go 5-6 nights a week. I had to start out slow but I would go 7 nights a week even if I only did very light workout being older in my 50's didn't want to push it I'm doing good now go every night usually 5 nights a week.
 
@PaulS

I am just curious if someone knows the biology of how/why it works since the effects and what I read do not make sense to me. I accept them as true, and I am fine with it. I am just curious about the HOW and WHY.

Tim
 
Think it might be the same reason it's easy to over pace early in a race. I forget the exact chemistry, but you basically "feel" more fit than you are until the effect wears off and then you are in a deficit mode. Been a while since I read the article, but it was focused on how starting an endurance event at slightly below race pace was better than starting too fast.
 
what does your breathing do when you start exercising?

It always lags; but I have not read anything about breathing rate and fitness. So I am not seeing the connection.

Tim
 
Question - how long afterwards does it stay elevated, and by how much?

Think of your heart as an auxiliary power supply for your body's muscles. When you first start to exercise your body doesn't know your plan - are you jogging to pick up a frisbee you dropped or is this the fist 20 yards of a marathon? Your body relies on the byproducts of exercise to decide when and how much to up-regulate all the aerobic adaptations - and increased HR is a big one. So is vasodilation, sweating, etc.
 
I’m doing a big climbing ride on Zwift (indoor trainer [Kickr for any who care]) as I write this. HR started out nice and even, first parts of the actual climbing section it spiked for about a minute (to ~145) then settled into a nice 134-135. When I push for a bit I’ll get up over 160 abs when I stomp on it I’ll cruise up to 175 for ~30 seconds before recovering at 140. Repeat. Within 5minutes after riding I’m back near resting HR of low 50s. (I rode well over 7000 miles last year, and the year before that, etc.)
 
Your stomps are incurring aerobic debt, but they aren't pushing your aerobic system to the limit. Even after you stop the effort it takes a while for your body to clear the byproducts of that effort and pay down your aerobic debt. Try a 1 minute maximum (and I mean maximum) and I don't think you'll see your HR go any higher when you stop.

Similarly I'm pretty sure if you do a field test (7k a year and a Zwift user I'm confident you know about these) you won't see a spike in HR after you stop.

The speed and degree to which your HR recovers after an effort (in the first couple of minutes) is a good indicator of aerobic fitness.
 
(also if anyone want's to meet up and ride on Zwift, pm me - the winter is long and cold ;))
 
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