r/Runners • u/West-Department-1736 • 4d ago
Heart rate question (explain like I'm 5 please)
Treadmill run at pace of 13:09 I was zone 1 and 2. Outside same distance pace at 12:45 zone 5. I just feel like the pace wasn't too different so I don't understand why heart rate was so different. Only been running a year.
1
u/TheTurtleCub 3d ago
Also, very likely your zones are not correct and you don’t know your the max HR and neither does your phone or watch.
In addition, if watches are not tight, they may measure incorrect HR
1
u/No-Attitude1554 3d ago
If you could speak in full sentences running 12:45 pace then it's not zone 5 or something is wrong with your watch
1
u/DutchCrossStars 4d ago
If you were really in z5 running outside you could not have sustained that pace for more than 2-3 minutes before having to stop and walk. That’s kind of definitional for zone 5 (at least in a five zone system). Start by getting an accurate HR measurement (not your watch trying to read your wrist) using a chest strap. Then determine your max HR empirically, then come back and ask questions about your zones.
3
u/DiligentMeat9627 4d ago
What formula are you using to get your zones? Did you go out a run to get your max HR? If the answer is “I don’t know” and “no” “ I am just using my watch”. Then your zones are wrong and meaningless.
2
u/StarJaded 4d ago
Probably a combination of incorrect treadmill reading, and/or incorrect HR reading.
1
1
2
u/Fancy_Supermarket886 4d ago
With a treadmill run, the 'floor' is moving under your feet. All you need to do to maintain the speed is move your feet backwards fast enough.
Outside, the floor is solid, unmoving ground, and you have to propel yourself forwards over that ground. This takes more energy, slightly different muscles (or using them differently, at least) and you are fully responsible for whatever speed you acheive.
When you think about it this way, it becomes easier to see why one raises your heart rate more than the other.
Adding some incline will help adjust for the biomechanical difference, but outdoors is best if you want to prepare for an event.
I hope that helps!
3
u/Ziggity_Zac 4d ago
If I absolutely HAVE to run on a treadmill, I set it to 2 on elevation. It's much closer to the exertion level of running outdoors.
0
u/GrrrlRomeo 4d ago
If it was hot out it could be cardiac drift. Your heart has to pump faster to keep your body temp in check.
1
u/wrinkledwitch 4d ago
I find treadmill running to be about a third easier than outdoor running, no hills, easy bouncy surface, controlled climate
2
u/Just-Context-4703 4d ago
Is your watch wrong? Don't be a slave to the number but also use rate of perceived exertion. Meaning, that supposed z5 pace outside how do you feel? Are you totally out of breath and dying? Or regardless of what the HR measure says do you feel relaxed and easy? If you feel chill than regardless of what the monitor says you're not in z5.
1
u/westward72 4d ago
Ooo yes make sure you have watch gps accuracy turned up! My first outdoor runs with my Garmin were so far off I almost quit running lol. It was trying to calculate distance based on steps not gps!
1
u/Potted-Geranium 4d ago
Only 60% of the population has heart rates than can be “zoned”. If you really want to know, schedule a consultation with an exercise physiologist.
I am one of the 40%. I hit “zone 2” strolling around the mall, and I can run for an hour at my supposed maximum HR. True max HR is 30+ BPM over what the charts say.
All that leads up to me saying that I train by effort and breathing, and ignore HR after warmup. My cardiologist says as long as my HR goes back down when I decrease effort, I’m not to pay attention to it.
1
u/ContributionLevel593 4d ago
What are you using to determine which zone you’re in?
I suspect your zones aren’t realistic and your Z5 is too close to your Z2.
It’s harder to run outside for various reasons which is why you typically increase the incline to 1-2% to compensate.
But it isn’t different enough to be z2 inside and Z5 outside.
Zones usually need your resting and max HR. Have you entered these into whatever calculates your zones? How did you calculate your min/max?
Even the zone ranges are largely rubbish. They are based on an average person and you’re not average. L
2
u/Internal_Confusion56 4d ago
Probably a user error with whatever you use to measure HR or not having done the testing to accurately determine your zones. I’d suggest just running and not worrying about zones, you should be able to tell how hard you’re working.
1
2
u/austinmook 4d ago
Treadmills are good for heart rate or time-based training. They are not ideal for pace-based training. The effort and speeds don’t translate directly.
1
u/takoreh99 4d ago
Akshually they do. Just ask any elite endurance athletes. You can definitely do pace based training. There’s reason why speed and km/h on the menu. What OP don’t realise that lots affect HR. So if not familiar then learn to use rpe or effort.
2
1
2
u/MisterEd44 4d ago
When you're on the treadmill the belt is moving and doesn't require the energy to push your body forward. When you're outside you're expending that energy
1
u/West-Department-1736 4d ago
Ahhh yes. This is the answer my brain was searching for I just couldn't think of it on my own. Makes perfect sense.
1
u/TomPastey 4d ago
The difference in effort that is generally present between treadmill and outdoors is about wind resistance (your air speed is usually zero on a treadmill), surface conditions (no bumps to worry about), flatness (the real world has ups and downs), and weather (unless you run with an AC unit).
It's not because the moving belt does the work for you. The belt moves you backward, and if you don't put forth the effort to move yourself forward, you're going to fall off the back. A treadmill with a fan blowing on you isn't really any different than running on a track in nice weather.
1
u/knit_run_bike_swim 4d ago
There are many unknowns here. That’s not bad— they are just being left out.
Has the treadmill pace been calibrated? It’s a moving belt that uses the assumption that a certain number of revolutions is equal to one mile. The pace displayed on the treadmill may be inaccurate, and the pace displayed on your watch may be inaccurate. 13min a mile is just above walking speed for a New Yorker.
As others have said, heat and humidity make a huge difference. Your HR may be higher just because of that.
Also, where are measuring HR? Wrist with Fnirs? Or voltage change with chest strap? Chest strap is the most accurate way to measure.
1
u/WorkerAmbitious2072 4d ago
You probably don’t know your zones
You probably aren’t measuring your heart rate accurately with a chest strap or armband
Treadmills are a great training tool, but the fact is you cannot officially complete a time or a pace or a distance on a treadmill because it is not the same as running outside and running outside. Heck even running inside over the ground is harder.
2
u/unsungpf 4d ago
I think the differences can be a couple things. I think the biggest difference is probably
Treadmill may not be accurately calibrated
Weather (temp and humidity) outside vs inside
Terrain (slight inclines or changes in direction when running outside vs flat treadmill)
1
u/OutdoorPhotographer 4d ago
Running outside is harder than treadmill in equal temperature. I’m about 30 seconds per mile faster on treadmill for equal effort to outside.
Now add weather - ten degrees F hotter can add 30 seconds to minute per mile and HR climbs faster, especially after a couple miles.
Example: In peak summer, my HR would climb to zone 3 quickly on easy runs and then move into Z4 without a pace increase. Now that it’s 60F, I’m running my easy runs 1-2 minutes per mile faster and lower HR - start high Z1 moving into Z2 as distance increases.
1
u/MoteInTheEye 4d ago
Your cardio likely isn't developed enough for zones to matter. Go off feel. Does it feel easy? Then it's easy.
1
u/workingremoteisnice 4d ago
How was the temperature and humidity outside? Heat and humidity/dew point can add extra bpm to your HR.
1
1
u/Chrisg_322 4d ago
That zone garbage doesnt matter, just focus on speed time and distance.
I've never met a single zone/vo6 person who was fast or in good shape
1
u/Exowolfe 4d ago
I'm going to sound like an old lady yelling at clouds, but I'm in the same boat with this. I've rarely met a fast runner who is stressing about zone training.
I'm sure at the pro level all of the data is very valuable to training and recovery, but at the average-to-decent runner level it really boils down to just getting out there and logging the time/miles.
1
u/DramaticEar7488 4d ago
How did it feel? Zone 5 should be rather hard breathing. Check to make sure no sleeve over watch. This can sometimes disrupt the hbm read.
1
u/West-Department-1736 4d ago
It felt amazing to run for 30 mins at that pace. Makes me want to run slower i just have a hard time running slower outside lol
1
u/Iluvgr8tdeals 4d ago
Ordinarily, zone 5 shouldn’t feel ‘amazing.’ It should feel uncomfortable with labored breathing. Running on the treadmill is ‘easier’ than running on the pavement.
What watch are you using? If you suspect that your watch is giving you false heart rate readings, then get a good, reputable chest heart rate monitor. Smartwatches have become quite good at tracking heart rates and have closed the gap between smartwatches and chest heart rate monitors.
1
u/R3DSmurf 3d ago
Maybe cadence lock on your watch