Heart-rate data does not behave the same way on foot and on the bike. These guides cover the artefacts specific to each sport and a recovery-reading routine built around the moments when a phone camera is actually reliable.
The short version: take your heart-rate readings when you are still, and set your zones separately for each sport. Running heart rate runs higher than cycling heart rate at the same perceived effort because you carry your own body weight and recruit more muscle, so reusing running zones on the bike makes every ride look easier than it was. Running also produces cadence lock, where an optical sensor latches onto your arm swing instead of your pulse; cycling produces cardiac drift, where the same watts cost more beats after two hours. Neither artefact touches a seated reading taken before you start or after you stop — which is exactly where the two protocols below place every measurement.
Three things differ enough to justify separate pages, and one thing is identical in both — which is the number worth building your week around.
Running can push an optical wrist sensor into reporting your step rate instead of your pulse when the two happen to converge — a runner at 170 steps per minute with a heart rate near 170 bpm is the textbook case. On a bike the problem is road buzz and grip pressure. Different mechanisms, same conclusion: trust the readings you take while stationary.
A power meter measures output directly and instantly, which makes heart rate’s lag obvious: watts jump with the pedal stroke while your pulse takes tens of seconds to follow, and keeps climbing after you ease off. Runners rarely have that second signal, so heart rate carries more of the load — and its artefacts matter more.
At matched effort most riders record a lower heart rate on the bike than on foot. If you set zones from a running test and reuse them cycling, your easy rides will look easier than they were and your hard rides will never reach the top zone. Test per sport, and keep the two series apart in your log.
Whatever you did yesterday, the reading you take lying still before you get up is the same measurement. That is the number that carries the trend across a training block, and it is the one both pages ask you to protect: same time, same posture, every day, whether yesterday was a long run or a four-hour ride.
If you are trying to work out why a heart-rate number looks wrong, find the effect below and read the page that explains it.
| Effect | What you actually see | Which sport it dominates | Read |
|---|---|---|---|
| Cadence lock | A suspiciously flat trace that matches your step rate rather than your pulse | Running — arm swing drives the artefact | Runners → |
| Cardiac lag | Heart rate still rising after the interval has already finished | Both, but it ruins short-rep pacing on foot | Runners → |
| Heart-rate recovery | How far the pulse falls in the minute after you stop | Running — you are standing still, so the camera reading is clean | Runners → |
| Power-to-heart-rate lag | Watts spike instantly; the heart-rate trace follows tens of seconds later | Cycling — visible only because you have a power trace to compare | Cyclists → |
| Cardiac drift | Same watts, steadily higher heart rate as a long ride goes on | Cycling — long steady efforts expose it most | Cyclists → |
| Vibration artefacts | Noisy optical readings on rough surfaces or with heavy grip pressure | Cycling — road buzz travels straight into the sensor | Cyclists → |
Each page carries its own artefact explanations and its own reading protocol, placed at the moments when a camera measurement is reliable for that sport.
Heart Rate Monitor for Runners — Free iPhone App (No Wearable)
Track resting HR, HRV, and recovery as a runner using just your iPhone. Pulse Rate helps you log training load, spot overreaching early, and run smarter.
Read more →Heart Rate Monitor for Cyclists — Free iPhone App (No Chest Strap)
Track resting HR, HRV, and cycling training load free on your iPhone. No Garmin, no chest strap needed for daily recovery monitoring between rides.
Read more →The sport pages assume you know what these numbers are. If any of them is unfamiliar, read the guide first.
HRV for beginners
What heart-rate variability is, why the trend matters more than the value, and how to read it.
Read more →TRIMP training load
How duration and intensity combine into one number per session, and what a sustainable week looks like.
Read more →Zone 2 training
Finding the easy aerobic band, and why the talk test beats a formula.
Read more →Resting heart rate
The slowest-moving signal you have, and the protocol that keeps it comparable.
Read more →These pages are about the readings around your sessions, not during them. Knowing the boundary saves you a disappointing first run.
Because the same heart-rate number means different things in each sport. Running produces cadence-lock artefacts on optical sensors and higher heart rates for the same perceived effort; cycling gives you a second, cleaner measurement in power, which exposes how slowly heart rate responds. The two pages describe different artefacts and different reading protocols, not the same advice with the noun swapped.
At a matched perceived effort most people see a lower heart rate on the bike, because you are supported by the saddle and recruiting less total muscle mass than when you carry your own weight on foot. It is not a fitness difference and it is not an error. The practical consequence is that heart-rate zones set from a running test will be wrong on the bike, so each sport needs its own zones.
No, and neither page suggests it. Optical measurement at the fingertip needs stillness — running arm swing and road vibration both destroy the signal, and on a bike you would have to let go of the bars. Camera readings belong before you start, in the minutes after you stop, and first thing the next morning. For live in-session heart rate, a chest strap remains the right tool.
Heart-rate recovery is how far your pulse falls in the minute after you stop a hard effort — a faster fall generally tracks with better aerobic fitness. It suits a phone camera unusually well, because you are standing still for it by definition. The runners page sets out a repeatable version: stop cleanly, start a reading at fifteen seconds, record the figure at one minute, then take the usual resting reading the next morning.
For pace, route and live in-session data, yes — Pulse Rate does not replace a GPS watch or a power meter, and it has no live workout mode. What it covers is the other half: the resting and recovery readings around your sessions, where overtraining actually shows up first, taken without any extra hardware.
Read the running page for the artefact explanations, since optical sensing is at its worst on foot and the failure modes are clearest there. Then read the cycling page for the power-to-heart-rate relationship and cardiac drift. Keep your zones separate by sport, and keep the morning resting reading identical for both — that number is sport-agnostic and it is the one that carries the trend.
Before the next session, take the resting reading. It is the number both of these guides are built on, and it takes sixty seconds.
Free download · Core heart-rate measurement free · iOS 15+