Caffeine Lowers Resting Heart Rate?

[anaconda]

I always thought that caffeine consumption would raise your RHR. But I've recently realized then when I wake up in the morning, my RHR (especially after a hard training session the night before and not enough sleep) is likely to be higher than later in the day, after 100mg of caffeine, sitting at my desk. Often 10+ BPM less.

I assumed that caffeine would raise my RHR if anything and was trying to find out why my morning RHR would be higher than later, after caffeine consumption.

Found this study which is interesting:

http://www.jissn.com/content/4/1/11

Background
The purpose of this study was to examine the cardiovascular effects of two low-levels of caffeine ingestion in non habitual caffeine users at various submaximal and maximal exercise intensities.

Methods
Nine male subjects (19

 

[Franklegit]

I'm a 20 year old who drinks his weight in coffee on some days. Interesting read.

 

[August West]

I would believe it, my pulse is around 62 in the afternoons and evenings, but in the morning it is sometimes approaching 80.

I drink a pot of strong coffee daily. Whether it's the caffeine or pulse is just naturally higher after waking I don't know.

 

[anaconda]

I don't know either so I hope some of the more knowledgeable posters chime in. They say your RHR should be measured right when you wake up but I sometimes wake up with a fast or even pounding heart. It is lower by the time I finish getting ready and everything and after I have caffeine too.

Conventional wisdom says caffeine is a stimulant and show raise your heart rate. I always thought it did.

 

[hardheart]

This catches my attention:

Caffeine at 1.5 and 3.0 mg/kg body weight significantly lowered (p < 0.05) HR during all three submaximal exercise intensities compared to placebo (range &#8211; 4 to 7 bpm lower) but not at rest or maximal exercise.

So, at medium intensity caffeine seemed to have an effect but at resting and max effort it did not. So, caffeine is not affecting your RHR according to this study.

 

[August West]

My BP seems high in the mornings also, like 130/90, not sure if there is a connection with pulse rate.

 

[anaconda]

This catches my attention:



So, at medium intensity caffeine seemed to have an effect but at resting and max effort it did not. So, caffeine is not affecting your RHR according to this study.

Yeah I read that too. Kind of why I'm asking -

As mentioned, conventional wisdom would think that caffeine would raise RHR. This study says it has no effect.

Personally, my RHR is higher right when I wake up than later in the day, and after caffeine.

I'm just trying to put the pieces together.

 

[Pathogenic]

This is an interesting find. For me, it is the exact opposite: my heart rate during moderate aerobic exercise is much higher on caffeine than when I don't take caffeine. Of course, my daily caffeine dosage would probably cause the average person to get meth bugs.

 

[anaconda]

This is an interesting find. For me, it is the exact opposite: my heart rate during moderate aerobic exercise is much higher on caffeine than when I don't take caffeine. Of course, my daily caffeine dosage would probably cause the average person to get meth bugs.

How much is it? I typically have 100mg 2x a day. Sometimes a little more (a half cup coffee on top of that) but not much.

This is usually at least 6 days a week and has been for months. Every once in a while I'll take a couple days off.

 

[Pathogenic]

How much is it? I typically have 100mg 2x a day. Sometimes a little more (a half cup coffee on top of that) but not much.

This is usually at least 6 days a week and has been for months. Every once in a while I'll take a couple days off.

Days off? What are those? ;p

320mg-375mg per day, on average. I usually get 250-300 in pill form in the morning as soon as I wake up, followed by several cups of green tea or diet soda throughout the day. Sometimes I stack it with modafinil. This wouldn't be a lot if I were >200 lbs, but I'm 160 right now, haha.

 

[Bulkhead]

Here is a youtube clip about coffee :58 seconds in it explains why coffee beans have caffeine, how much caffeine it takes to kill someone, and why it is the "greatest drug ever"

https://www.youtube.com/watch?feature=player_detailpage&v=OTVE5iPMKLg

 

[xilliun]

I always understood caffeine to increase BP and lower HR or have no effect on it. They make note in the discussion that they found 3 studies in agreement with their results and 15 others which didn't align.

They later discuss why there's an effect submaxmially, and not at max effort

Based on the previous discussion it could be that contractility or preload cannot be further optimized at high exercise intensity and therefore the caffeine effect is negated. Further follow-up caffeine studies measuring stroke volume would need to be conducted in order to fully illuminate this question.

Very interesting study but.

 

[JRT6]

My RHR should in the 20's then. I get up to a gram a day before I reset.

 

[Pathogenic]

My RHR should in the 20's then. I get up to a gram a day before I reset.

You make me look like a massive puss.

 

[AboveThisFire]

I'm what you would call a "habitual caffeine user" so I'm not sure I get the benefits haha. Guess it's just cardio work for me

 

[hardheart]

My RHR should in the 20's then. I get up to a gram a day before I reset.

You make me look like a massive puss.

That's cute. No, really.

I haven't reset in a while

 

[anaconda]

How long does it take for a reset?

 

[hardheart]

How long does it take for a reset?

2~ weeks. A reset, at least and I'm referring to it, is reconditioning your body to be sensitive to caffeine again. So, when you drink a cup of coffee and still feel sloggy, you know you need a reset.

There are pills out there that help with it. There used to be one called Reset AD I think. Used it once. Was amazing.

 

[JRT6]

Reset AD was discontinued by the manufacturer and the replacements are poorly rated.

 

[anaconda]

2~ weeks. A reset, at least and I'm referring to it, is reconditioning your body to be sensitive to caffeine again. So, when you drink a cup of coffee and still feel sloggy, you know you need a reset.

There are pills out there that help with it. There used to be one called Reset AD I think. Used it once. Was amazing.

Reset AD was discontinued by the manufacturer and the replacements are poorly rated.

Yeah I used it before and had good results. Who knows if it worked or was just placebo.

Two weeks seems like a good time frame. Is there anything scientific to support a certain period or is this just anecdotal? Sometimes just 2-3 days makes a huge difference for me.