Regular aerobic exercise has the best evidence for raising your resting heart rate Resting heart rate How many times your heart beats per minute while you are fully at rest. For adults it is usually 60 to 100 beats per minute, and lower in well-trained athletes. More about Resting heart rate variability (HRV), and it takes about a month or more to show. Cutting back on alcohol and protecting your sleep remove the most common causes of low readings, while slow breathing raises HRV mostly while you are doing it; meditation, saunas and cold plunges have little or no evidence of a lasting effect.
Start with a realistic goal
Your HRV is partly set by things you cannot change. In morning readings from 28,175 app users, HRV fell with age, and physical activity level was only weakly linked to it (Altini and Plews, 2021). So the realistic aim is a modest rise over weeks, plus fewer of the dips that drag your average down.
Most studies on this page report RMSSD RMSSD Root mean square of successive differences: an HRV metric built from how much each heartbeat interval differs from the next. It mainly reflects vagal activity. More about RMSSD or high-frequency ( HF HF power The share of heart rate variability in fast rhythms of 0.15 to 0.40 Hz, the range of normal breathing. It mainly reflects vagal activity when breathing is 9 to 24 breaths a minute. More about HF power ) power. The 1996 Task Force standards define RMSSD as the square root of the mean squared differences between successive normal beats, and HF power as the 0.15 to 0.4 Hz band of the heart rate signal. Both mainly reflect the vagus nerve Vagus nerve The main nerve of the parasympathetic nervous system, running from the brainstem to the heart, lungs and gut. Its fast signals to the heart drive most beat-to-beat HRV. More about Vagus nerve , the “ rest and digest Parasympathetic nervous system The "rest and digest" branch of the autonomic nervous system. It slows the heart, mainly through the vagus nerve, and drives most of the beat-to-beat variation in HRV. More about Parasympathetic nervous system ” brake on your heart (Task Force, 1996).
The evidence at a glance
We rate evidence as strong when several trials or a meta-analysis agree, moderate when the direction is consistent but studies are small or indirect, weak when it rests on one or two small studies, and null when good trials found no effect. “Effect size” figures (d or g) compare groups on a common scale: about 0.2 is small, 0.5 medium and 0.8 large.
| Lever | Typical effect on resting HRV | Strength of evidence | Time to effect | Key source |
|---|---|---|---|---|
| Regular aerobic exercise | Rise in vagal HRV, medium in size (d = 0.48 for HF power across 13 studies); possibly smaller in older people | Strong | About 4 weeks in one training study | Sandercock 2005, Grässler 2021 |
| Enough sleep | Sleep loss lowered RMSSD across 11 trials (549 people); extra sleep was not tested | Moderate (for the harm of sleep loss) | Next night | Zhang 2025 |
| Regular sleep times | Slightly lower next-morning HRV after a less regular bedtime | Weak (one 28-day study of 54 students) | Next morning | Wang 2026 |
| Less alcohol | Removes a dose-related drop; HRV was 12% lower after heavy drinking in morning data | Strong (for the nightly drop) | Same night | Pietilä 2018, Altini 2021 |
| Slow breathing (about 6 a minute) | Large rise during practice; higher after single sessions and after programmes | Strong during; moderate afterwards | During practice; weeks for lasting change | Laborde 2022 |
| HRV biofeedback HRV biofeedback A breathing practice in which you watch your heart rate live and breathe slowly, often near 6 breaths a minute, to make the heart's rise and fall with each breath as large as possible. More about HRV biofeedback | In heart patients, SDNN SDNN The standard deviation of all NN intervals in a recording, in milliseconds. It measures overall variability, and its value depends strongly on how long the recording lasts. More about SDNN rose but HF power did not change | Moderate to weak (most trials at some risk of bias) | Unclear | Kaneko 2026 |
| Meditation | No clear rise over control (g = 0.19 after removing an outlier, not significant) | Null (19 randomised trials) | No effect shown | Brown 2021 |
| Sauna | No added change after 8 weeks on top of exercise | Null (one randomised trial of 38 adults) | No lasting effect shown | Lee 2025 |
| Cold exposure | Short rise in RMSSD (SMD = 0.61) that lasted up to 15 minutes after | Moderate for the short rise; none for lasting change | Minutes | Jdidi 2024 |
| Weight loss (if overweight) | Most of 12 studies found better vagal HRV after losing weight | Moderate to weak (small, varied studies) | Unclear | Mattos 2022 |
| Caffeine timing | Caffeine itself did not change HRV; late caffeine cut sleep, which can lower HRV | Indirect | Next night | Rauh 2006, Drake 2013 |
| Stress management programmes | Small rise (d = 0.27) in heart patients, mostly from biofeedback | Moderate to weak | Unclear | Gathright 2024 |
What each lever does
Regular aerobic exercise
A 2005 meta-analysis pooled 13 training studies (322 people) and found that HF power rose by a medium-sized effect. There was a trend towards a smaller rise in older people. A 2021 review of 26 studies in healthy adults (average ages up to 44) found that endurance, strength, high-intensity and mixed training all improved HRV when programmes lasted at least four weeks, with higher intensity and more frequent sessions more likely to help. The authors also flagged weaknesses in how many studies were run.
Change takes weeks. In a training study described by Buchheit, people starting an endurance programme saw their exercise heart rate improve within a week, but their resting HRV changed only after the fourth week (Buchheit, 2014). Expect short dips too: in the large app data set, HRV changed by about 4.6% after training. The training page explains how to read them.
Alcohol and sleep
These two work by removing dips. In 4,098 Finnish employees, an HRV-based recovery score in the first three hours of sleep fell by 9.3, 24.0 and 39.2 percentage points after low, moderate and high alcohol intake, compared with each person’s alcohol-free nights. The effect appeared even at low doses. See alcohol and HRV.
For sleep, a 2025 meta-analysis of 11 trials found that sleep deprivation lowered RMSSD, while SDNN and HF power did not change significantly. The evidence is about losing sleep; these trials did not test whether sleeping longer than usual raises HRV. One 28-day study in 54 sport students found that next-morning HRV was a little lower when their sleep timing drifted from their usual pattern, but it could not show cause and effect. More in HRV and sleep.
Slow breathing and HRV biofeedback
Breathing at about six breaths a minute makes your heart rate rise and fall in step with each breath, and HRV jumps while you do it. A 2022 review of 223 studies found higher vagal HRV during slow breathing (172 studies), right after one session (16 studies) and after programmes of several sessions (49 studies). See can breathing exercises raise your HRV?
HRV biofeedback adds a live heart rate display to slow breathing. A 2020 review of 58 randomised trials found small to moderate benefits for symptoms such as anxiety and depression. It did not pool resting HRV. A 2026 review of 13 trials in people with heart disease found that SDNN rose, but HF power did not change, and most trials had some risk of bias.
Meditation
A 2021 meta-analysis of 19 randomised trials found that mindfulness and meditation programmes did not raise resting vagal HRV more than control conditions. After one outlier was removed, the effect was small and not significant (g = 0.19). We cover this in more detail in does meditation raise HRV?
Sauna and cold exposure
In an 8-week trial, 38 inactive adults aged around 49 with at least one heart risk factor were assigned to exercise plus a 15-minute sauna, exercise alone, or no change. Exercise improved some HRV measures. Adding the sauna made no further difference. Cold exposure does change HRV, but only briefly. A 2024 meta-analysis of cold-water immersion and cold-air sessions found that RMSSD rose with cold exposure and stayed higher for up to 15 minutes afterwards, along with a small rise in blood pressure. No lasting change in resting HRV was shown. See do saunas or cold plunges raise HRV?
Weight, caffeine and stress
A 2022 review of 12 studies in people with overweight or obesity, mostly using diet, found that most showed better vagal HRV after weight loss, though the authors called for more standard HRV methods. For caffeine, 100 or 200 mg did not change HRV over 90 minutes in 30 men who used caffeine every day. Timing matters through sleep instead: 400 mg taken up to 6 hours before bed disturbed sleep in a home study of 12 adults (Drake and colleagues, 2013). For stress, a 2024 meta-analysis of programmes in adults with heart disease found a small rise in vagal HRV, mostly from biofeedback.
How to test a change on yourself
Single readings swing too much to judge a habit. In 10 runners on a 9-week programme, changes in fitness matched the week’s average HRV far better than a reading from one isolated day (Plews and colleagues, 2013).
- Measure the same way every time: same device, time and position.
- Build a baseline Baseline Your own usual HRV level and range, built from weeks of readings taken the same way. Comparing a reading with your baseline says more than comparing it with other people. More about Baseline first. The lesson on building your HRV baseline shows how.
- Change one habit at a time where you can.
- Compare 7-day averages before and after, over at least a month.
- Never take your daily reading during or right after a breathing session, sauna or cold plunge.
When to talk to a doctor
Ask a doctor before starting hard exercise, sauna or cold-water routines if you have a heart condition, high blood pressure or other health concerns. If your HRV stays well below your usual range for weeks with no clear reason, or you have chest pain, fainting, breathlessness or a racing or uneven heartbeat, get checked rather than trying to fix the number. HRV cannot diagnose anything. What does a low HRV mean? explains when a low reading is worth a visit.