Resting heart rate elevated
The marker under stimulants. Worth noting: suppressing it pharmacologically removes the warning, not the strain.
Caused by
7Substances on this site that list this effect.
What works against it
2Substances used against it. Descriptive — not a recommendation to take them.
What you can do yourself
No compound involved — the part that comes down to dose, training and everyday habits. Often the larger lever, and always the cheaper one.
Reduce, don't mask
Suppressing the number pharmacologically removes the warning, not the strain behind it.
Caffeine has a clock
It stacks with everything else and stays active for hours. Where it sits in the day matters as much as the amount.
Look at sleep
A bad night raises resting heart rate on its own. The value is often reporting the night, not the compound.
How you notice it
Resting heart rate on waking, before getting up. A watch is enough for the trend; the absolute number matters less than the change.
Connected to
Effects that share a cause with this one, get confused with it, or follow from overcorrecting it.
Descriptive, not a recommendation. That a countermeasure exists does not make the cause harmless.