43 FACTORS · 5 CATEGORIES · PEER-REVIEWED
What actually moves your HRV?
Every supplement, habit, exercise and nutrient with a measured effect on heart-rate variability, ranked by evidence strength, with the direction of effect and the dose that produced it. No guessing, just data.
Biggest controllable hit
dose-dependent
−13ms
RMSSD lost at the highest drinking level. Even one drink lowers HRV, and being young and fit does not protect you.
Pietilä et al. 2018 · JMIR Mental Health
43
Factors analysed
23
That raise HRV
13
Strong-evidence factors
29
Peer-reviewed sources
Quick Answers
The top research-backed picks across every category.
Protect First
Sleep
Key stat: Meta-analysis, n=549
Sleep loss lowered RMSSD, the number Fitbit and most wearables show, in a meta-analysis of 11 RCTs.
Category: Lifestyle
Best Exercise
HIIT
Key stat: NMA, 29 RCTs, n=1,317
#1 for RMSSD and SDNN in a network meta-analysis of 29 RCTs
Category: Exercise
Best Supplement
Ashwagandha (Witholytin)
Key stat: RCT, n=111
RMSSD rose 9% over 12 weeks while the placebo group fell 19%. It protects HRV under stress rather than raising it.
Category: Supplements
Best Nutrient
Vitamin D & B12
Key stat: Only if deficient
Being deficient in either is linked to lower HRV. No evidence topping up helps if your levels are already fine, so test first.
Category: Micronutrients
Quickest Impact
Slow Breathing (6/min)
Key stat: SDNN up by week 4
20 minutes a day at about 6 breaths a minute raised SDNN within 4 weeks, though RMSSD didn't change significantly.
Category: Lifestyle
Biggest HRV Killer
Alcohol
Key stat: RMSSD −2 to −13ms
RMSSD drops 2 to 13 ms per dose, and fitness doesn't protect you
Category: Lifestyle
Do More / Cut Back
The changes with real evidence behind them, with the dose that was tested and what it did. Tap any row for the full study details.
Do more
12 habits and supplements that raise HRV
- HIIT 2–3 sessions/week, with recovery #1 for RMSSD and SDNN Strong evidence
- Regular exercise Any structured training RMSSD up vs no training Strong evidence
- Slow breathing 20 min/day at 6 breaths/min SDNN up after 4 weeks Moderate evidence
- Resistance training 2–3 sessions/week #1 for HF power Moderate evidence
- Cardio + strength 3–5 days/week #1 for LF power Strong evidence
- Cold exposure 3 min cryotherapy (-110°C) RMSSD +54–85% short term Moderate evidence
- HRV biofeedback 10–20 min, several times/week Positive across RCTs Moderate evidence
- Time in nature 2+ hours in a forest Higher HF than city (n=280+) Moderate evidence
- Ashwagandha 200 mg twice daily (Witholytin) Kept RMSSD from dropping Moderate evidence
- L-Theanine 200 mg daily Blunts acute stress response Moderate evidence
- Beetroot juice ~400 mg nitrate RMSSD +6.7 ms post-workout Moderate evidence
- Vitamin D & B12 Only if you are deficient Low levels, lower HRV Moderate evidence
Show all 12
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Cut back
7 things that pull HRV down
- Sleep loss Short or missed nights RMSSD down (11 RCTs) Strong evidence
- Alcohol Any amount; more drinks, bigger hit RMSSD −2 to −13 ms by dose Strong evidence
- Smoking Including secondhand smoke HRV down by dose Strong evidence
- Chronic stress Cumulative load, not one bad day Keeps fight or flight on Strong evidence
- Dehydration Even mild, in the heat RMSSD and SDNN down Moderate evidence
- Overtraining Watch your 7-day HRV average Falling HRV may flag overreaching Moderate evidence
- High altitude Above ~2,500 m; reverses on descent HF drops (meta-analysis) Strong evidence
Show all 7
Only factors you can change, with strong or moderate evidence. Supplements with faded or patient-only results are left out; they stay in the full list below.
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Explore All Factors
Tap any factor to see mechanism, dosage, and source.
Lifestyle
18
Supplements
8
Exercise
6
Micronutrients
5
Demographics
6
Lowers HRV
Raises HRV
Protects HRV
You can't change these, but they explain your baseline. Two people can be equally healthy with very different HRV, so compare yourself to your own trend, not to someone else's number.
Lowers HRV
Age
HRV down with age
Evidence: Strong
Plain English
HRV naturally drops as you age, so compare yourself to your own baseline, not someone else's number.
Mechanism
Progressive loss of sinoatrial node pacemaker cells and reduced vagal nerve fiber density with aging.
Dosage / Context
Non-modifiable; compare to your own baseline
Source
Varies
Sex
HRV higher in women
Evidence: Strong
Plain English
Women typically have a stronger rest & digest tone. Differences narrow after 50.
Mechanism
Estrogen enhances vagal tone; testosterone promotes sympathetic activity. Menopause reduces HF power.
Dosage / Context
Non-modifiable
Source
Varies
Time of Day
HRV higher at night, lower in the morning
Evidence: Strong
Plain English
Your HRV naturally peaks overnight and dips in the morning, so only compare overnight readings to other overnight readings.
Mechanism
Suprachiasmatic nucleus drives 24h autonomic oscillation: parasympathetic peak during sleep, sympathetic peak at waking.
Dosage / Context
Compare overnight readings to overnight readings
Source
Lowers HRV
BMI / Body Fat
HRV down with higher BMI
Evidence: Strong
Plain English
Excess body fat suppresses HRV. Losing weight helps restore it.
Mechanism
Adipose-derived inflammatory cytokines impair vagal function; visceral fat particularly harmful via mechanical and hormonal effects.
Dosage / Context
Maintain healthy BMI; weight loss improves HRV
Source
Lowers HRV
Menstrual Cycle
HRV lowest before your period (n=1,004)
Evidence: Strong
Plain English
HRV drops after ovulation and is lowest in the days right before your period.
Mechanism
Vagal activity shifts across the cycle: higher in the follicular phase, lower in the luteal phase after ovulation.
Dosage / Context
Non-modifiable; track your cycle to put HRV in context
Source
Varies
Genetics
Twin studies yes; gene studies no (n=6,740)
Evidence: Emerging
Plain English
Your genes probably matter, but researchers haven't pinpointed which ones. Don't blame genetics; lifestyle still dominates.
Mechanism
Twin studies show heritability ~40–50%, but GWAS (n=6,740) found no significant loci. Polygenic effects likely.
Dosage / Context
Non-modifiable; lifestyle dominates
Source
Keep exploring
Vitamin B12
Lower HRV when deficient
Evidence: Moderate
Plain English
Being deficient is linked to lower HRV. No evidence topping up helps if your levels are already fine.
Mechanism
Essential cofactor for myelin synthesis and nerve conduction. Deficiency causes demyelination of autonomic fibers.
Dosage / Context
Only if deficient; RDA 2.4 mcg
Source
Check it out on Amazon
Raises HRV
Vitamin D
Lower HRV when deficient
Evidence: Moderate
Plain English
Being deficient is linked to lower HRV. No evidence topping up helps if your levels are already fine.
Mechanism
VDR expression on cardiomyocytes and autonomic neurons; deficiency increases inflammatory cytokines.
Dosage / Context
Only if deficient; get levels tested first
Source
Check it out on Amazon
Mixed
Omega-3 (EPA/DHA)
HF up, RMSSD unchanged (15 studies)
Evidence: Moderate
Plain English
Fish oil boosted one rest & digest measure (HF), but RMSSD, the number Fitbit shows, didn't change.
Mechanism
Membrane incorporation alters ion channel kinetics; anti-inflammatory effects via resolvin/protectin pathways.
Dosage / Context
1–2 g EPA+DHA daily
Source
Check it out on Amazon
Raises HRV
Zinc
Improved offspring HRV
Evidence: Emerging
Plain English
Interesting but niche: zinc during pregnancy improved the baby's HRV for years. Limited adult data so far.
Mechanism
Zinc-dependent enzymes in autonomic neurodevelopment; prenatal supplementation affects fetal ANS maturation.
Dosage / Context
RDA 8–11 mg; prenatal context
Source
Check it out on Amazon
Mixed
Magnesium
HRV results inconsistent across studies
Evidence: Weak
Plain English
Results are inconsistent, likely because dose, form and duration vary so much between studies.
Mechanism
Natural calcium channel blocker; stabilizes cardiac membrane potential and modulates NMDA receptors.
Dosage / Context
200–400 mg elemental Mg daily
Source
Check it out on Amazon
Keep exploring
Ashwagandha (Witholytin)
RMSSD up 9% vs down 19% on placebo (n=111)
Evidence: Moderate
Plain English
This one didn't boost HRV much but stopped it from dropping over 12 weeks, unlike the placebo. Also cut fatigue nearly in half (-46% vs -31% on placebo).
Mechanism
Adaptogenic withanolides modulate cortisol and reduce sympathetic overdrive, preserving vagal tone under stress.
Dosage / Context
200 mg twice daily (Witholytin extract)
Source
Check it out on Amazon
Raises HRV
Ashwagandha (Zenroot)
Early HRV bump that faded (RCT, n=90)
Evidence: Moderate
Plain English
Quick early bump in HRV that faded. Stress and anxiety kept improving though, so still useful for mood.
Mechanism
Initial vagal stimulation via cortisol reduction; tolerance may develop for HRV-specific effects.
Dosage / Context
500 mg daily (Zenroot KSM-66 extract)
Source
Check it out on Amazon
Raises HRV
Polyphenols
Anti-inflammatory; limited human HRV data
Evidence: Moderate
Plain English
Colorful plant compounds (berries, dark chocolate, green tea) fight inflammation, which helps your nervous system relax.
Mechanism
Antioxidant and anti-inflammatory effects reduce oxidative stress on cardiac autonomic neurons.
Dosage / Context
Dietary sources preferred; supplements vary widely
Source
Raises HRV
Multivitamin
Slowed HRV decline (1 RCT, dialysis patients)
Evidence: Moderate
Plain English
Like Ashwagandha Witholytin, it protected HRV from declining rather than actively raising it. Evidence is from a single RCT on hemodialysis patients, not healthy adults, so take it with a grain of salt.
Mechanism
Corrects subclinical micronutrient deficiencies that impair autonomic nerve function.
Dosage / Context
Standard daily multivitamin
Source
Check it out on Amazon
Raises HRV
GABA
Shifted toward rest mode (RCT, n=30)
Evidence: Moderate
Plain English
The brain's main 'calm down' chemical. Supplementing shifted the nervous system toward rest-and-recover mode.
Mechanism
GABAergic inhibition of central sympathetic outflow shifts autonomic balance toward parasympathetic dominance.
Dosage / Context
100–200 mg daily
Source
Check it out on Amazon
Raises HRV
L-Theanine
Blunts the acute stress response
Evidence: Moderate
Plain English
The calming amino acid in green tea. Lowers cortisol and takes the edge off your fight-or-flight response.
Mechanism
Crosses blood-brain barrier, increases alpha waves and GABA, reduces cortisol and sympathetic activation.
Dosage / Context
200 mg daily
Source
Check it out on Amazon
Raises HRV
Beetroot Juice
RMSSD up 6.7 ms post-exercise (n=54)
Evidence: Moderate
Plain English
Nitrates boost nitric oxide, helping HRV bounce back quicker after workouts. Only studied in postmenopausal women so far.
Mechanism
Dietary nitrate → nitric oxide pathway enhances vascular function and parasympathetic reactivation post-exercise.
Dosage / Context
~400 mg nitrate (70 mL concentrated juice)
Source
Check it out on Amazon
Raises HRV
Probiotics
Better HRV markers in hypertensive women
Evidence: Emerging
Plain English
Your gut talks to your brain via the vagus nerve. Specific strains (L. paracasei LPC-37, L. rhamnosus HN001, L. acidophilus NCFM, B. lactis HN019) reduced inflammation markers that correlated with better HRV in hypertensive women. Higher gut microbial diversity is also associated with higher SDNN.
Mechanism
Probiotic-driven colonization produces SCFAs (butyrate, acetate, propionate) that reduce inflammation and engage the vagus nerve. Higher gut microbial diversity associated with higher SDNN.
Dosage / Context
Multi-strain, CFU counts vary by product
Source
Check it out on Amazon
Keep exploring
HIIT
#1 for RMSSD and SDNN (29 RCTs, n=1,317)
Evidence: Strong
Plain English
The single best exercise type for improving HRV across the main metrics.
Mechanism
High-intensity intervals drive large cardiac output demands, stimulating vagal remodeling during recovery.
Dosage / Context
2–3 sessions per week, with adequate recovery
Source
Raises HRV
Regular Exercise (any type)
RMSSD up vs no training (n=623)
Evidence: Strong
Plain English
Any structured training (cardio, weights, HIIT) raised RMSSD vs people who didn't train.
Mechanism
Regular training upregulates cardiac vagal tone and improves baroreflex sensitivity.
Dosage / Context
Any structured training program (cardio, weights or HIIT)
Source
Raises HRV
Combined (Aero + RT)
#1 for LF power (NMA)
Evidence: Strong
Plain English
Doing both cardio and weights gives complementary benefits. Best of both worlds for overall autonomic health.
Mechanism
Synergistic cardiovascular and neuromuscular adaptations optimize autonomic balance across frequency domains.
Dosage / Context
Mix of cardio and strength, 3–5 days/week
Source
Raises HRV
Resistance Training
#1 for HF power (29 RCTs, n=1,317)
Evidence: Moderate
Plain English
Lifting weights helps HRV, especially the rest & digest side. HIIT still ranked higher for RMSSD.
Mechanism
Post-exercise parasympathetic reactivation and chronic reductions in resting sympathetic tone.
Dosage / Context
2–3 sessions per week, progressive overload
Source
Lowers HRV
Overtraining
HRV down with overreaching
Evidence: Moderate
Plain English
If your HRV keeps trending down during hard training, you may be doing too much. Less reliable in endurance athletes. Watch your 7 day average, not single nights.
Mechanism
Excessive training load without recovery causes chronic sympathetic activation and vagal withdrawal.
Dosage / Context
Monitor 7-day rolling HRV average to avoid
Source
Raises HRV
Yoga
RMSSD up (n=90, students only)
Evidence: Weak
Plain English
Yoga improved HRV and lowered anxiety, but the studies are few, small and only in students.
Mechanism
Pranayama (breathing) component may drive effects via respiratory sinus arrhythmia; asana effects less clear.
Dosage / Context
Regular practice; studied in students only
Source
Keep exploring
Sleep Loss
RMSSD down after sleep deprivation (11 RCTs, n=549)
Evidence: Strong
Plain English
Nothing surprising here. Bad sleep = bad HRV, and RMSSD (the number Fitbit shows) takes the hit.
Mechanism
Nocturnal parasympathetic dominance requires uninterrupted sleep architecture. Fragmented sleep elevates sympathetic tone.
Dosage / Context
Seen after sleep deprivation; protect 7–9 hours on a consistent schedule
Source
Lowers HRV
Alcohol
RMSSD down 2.0 / 5.7 / 12.9 ms by dose (n=4,098)
Evidence: Strong
Plain English
Even 1 drink lowers HRV. More drinks, bigger hit. Being young and fit does NOT protect you.
Mechanism
Ethanol suppresses vagal tone and activates sympathetic nervous system in dose-dependent fashion.
Dosage / Context
Any amount lowers HRV; more drinks, bigger hit
Source
Lowers HRV
Smoking
HRV down by dose, including secondhand
Evidence: Strong
Plain English
Damages vagal tone directly. Even secondhand smoke at home or work lowers HRV.
Mechanism
Nicotine activates sympathetic ganglia; smoke particulates cause systemic inflammation damaging vagal nerve fibers.
Dosage / Context
Any exposure, including secondhand smoke at home or work
Source
Lowers HRV
Chronic Stress
HRV down with stress
Evidence: Strong
Plain English
Keeps your fight or flight system turned on. A common reason people have persistently low HRV.
Mechanism
HPA axis dysregulation with sustained cortisol elevation suppresses vagal tone and shifts autonomic balance.
Dosage / Context
Cumulative exposure; management is key
Source
Lowers HRV
Altitude
Sympathetic spike, HF drops above ~2,500m (meta-analysis)
Evidence: Strong
Plain English
Thinner air forces your body into fight-or-flight mode to keep oxygen flowing. HRV recovers when you come back to lower elevation. Don't panic about low readings at altitude. It's expected.
Mechanism
Hypoxia-driven sympathetic activation and reduced parasympathetic (HF) power. Chemoreceptor-mediated response to lower O₂ partial pressure.
Dosage / Context
Effect begins above ~2,500m; reversible on descent
Source
Raises HRV
Slow Breathing (6/min)
SDNN up after 4 weeks (n=50); RMSSD unchanged
Evidence: Moderate
Plain English
Breathing at 6 breaths per minute hits your body's "resonance frequency." 20 min/day raised overall HRV, though RMSSD didn't change significantly.
Mechanism
Respiratory sinus arrhythmia at ~0.1 Hz resonance frequency maximizes baroreflex sensitivity and vagal output.
Dosage / Context
20 minutes daily at 6 breaths/min
Source
Check it out on Amazon
Raises HRV
Cold Exposure
RMSSD up 54–85% after one session (n=40)
Evidence: Moderate
Plain English
Cold shocks your vagus nerve awake. A 3 min cryotherapy session (-110°C) gave a big short-term HRV jump. Ice baths and cold showers weren't tested here.
Mechanism
Sudden whole-body cold triggers a reflex rise in vagal (parasympathetic) activity. HRV was measured once, 5 minutes after the session.
Dosage / Context
3 min whole-body cryotherapy at -110°C; short-term effect only
Source
Check it out on Amazon
Raises HRV
HRV Biofeedback
Effect sizes across RCTs
Evidence: Moderate
Plain English
Using real-time HRV data to train yourself to control your nervous system. Works for stress, anxiety, and sports.
Mechanism
Operant conditioning of baroreflex sensitivity through paced breathing at resonance frequency with visual feedback.
Dosage / Context
10–20 minute sessions, several times per week
Source
Raises HRV
Forest Bathing
HF higher in forest vs city (n=280+)
Evidence: Moderate
Plain English
Being in nature measurably calms your nervous system. Not just 'feeling relaxed'; it shows up in the data.
Mechanism
Phytoncides (tree terpenes) and reduced sensory stressors lower cortisol and sympathetic activation.
Dosage / Context
2+ hours in forested environment
Source
No clear effect
Caffeine
No effect on post-exercise RMSSD (meta-analysis, p=0.77)
Evidence: Moderate
Plain English
A meta-analysis found caffeine didn't change how fast RMSSD recovers after exercise.
Mechanism
Adenosine receptor antagonism raises alertness, but pooled data show no measurable effect on post-exercise vagal recovery.
Dosage / Context
~200 mg doses tested
Source
No clear effect
Sauna
No HRV benefit beyond exercise alone
Evidence: Moderate
Plain English
HRV dips in the heat and rebounds during cooldown, but regular sauna use didn't add any HRV benefit beyond what exercise alone did.
Mechanism
Acute heat stress activates sympathetic response. Post-cooling parasympathetic rebound. Chronic adaptation unclear.
Dosage / Context
15–20 min sessions, 80–100°C
Source
Raises HRV
Caloric Restriction
CR practitioners had HRV 20 years younger than age-matched controls (n=42)
Evidence: Moderate
Plain English
Eating ~30% below caloric needs while staying nutritionally complete helps your autonomic nervous system stay younger. Mechanism is reduced inflammation and improved insulin sensitivity (hormesis). Not the same as starvation: a meta-analysis found moderate CR doesn't raise cortisol, only fasting/starvation does. Combined with exercise the effect is even stronger.
Mechanism
Reduced inflammation and improved insulin sensitivity via hormesis. Caloric restriction without malnutrition preserves vagal tone and autonomic flexibility.
Dosage / Context
~25-30% caloric reduction while maintaining full nutrition
Source
Lowers HRV
Dehydration
RMSSD and SDNN down, HR ~6 bpm up (n=68)
Evidence: Moderate
Plain English
Even mild dehydration (skipping 2 glasses of water over 4 hours in the heat) lowered HRV, raised heart rate ~6 bpm and raised anxiety.
Mechanism
Hypovolemia reduces venous return, triggering compensatory sympathetic activation and reduced parasympathetic outflow.
Dosage / Context
Even mild (~0.6% body weight lost); stay hydrated in the heat
Source
Raises HRV
Sexual Activity
Associated with higher resting HRV (n=120)
Evidence: Emerging
Plain English
Associated with higher resting HRV but causation is unclear. Healthier people may simply have more sex. Interesting signal but don't read too much into it yet.
Mechanism
Possible oxytocin-mediated vagal activation and stress reduction. Confounded by overall health status.
Dosage / Context
Observational; no dosage established
Source
Raises HRV
Meditation
HF power up during a 20 min session (n=27)
Evidence: Weak
Plain English
20 minutes of nondirective meditation raised HRV while people were doing it. No special technique needed.
Mechanism
Reduces cortisol, shifts autonomic balance toward parasympathetic via prefrontal-amygdala regulation.
Dosage / Context
20 min session; HRV measured during meditation only
Source
Check it out on Amazon
No clear effect
Intermittent Fasting
No RMSSD change (p=0.84)
Evidence: Weak
Plain English
The study behind the popular 16:8 claim found no significant change in RMSSD. There's no good evidence yet that a fasting window moves HRV either way.
Mechanism
Proposed: lower inflammatory load could support vagal tone, but this has not shown up in HRV data.
Dosage / Context
16:8 protocol tested; no HRV effect found
Source
Raises HRV
Mediterranean Diet
HRV up with diet (1 study)
Evidence: Weak
Plain English
Anti-inflammatory foods (fish, olive oil, veggies) support a calmer nervous system. Diets heavy in saturated fat, trans fat and high glycemic carbs do the opposite.
Mechanism
Anti-inflammatory dietary pattern reduces systemic inflammation and oxidative stress on autonomic neurons.
Dosage / Context
Daily dietary pattern
Source
Lowers HRV
THC / Cannabis
Overnight RMSSD down 11–19 ms (pilot, n=18)
Evidence: Weak
Plain English
Suppresses your rest & digest system overnight. Sleep HRV took a clear hit the night of use, even in regular users.
Mechanism
CB1 receptor activation suppresses parasympathetic outflow during sleep, reducing nocturnal vagal tone.
Dosage / Context
Seen the night of use, even in regular users
Source
Keep exploring
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Sources
All data sourced from peer-reviewed studies and meta-analyses.
Supplements
Smith et al. 2023: Ashwagandha (Witholytin) RCT
doi.org
Supplements
Thakkar et al. 2025: Ashwagandha Zenroot RCT
link.springer.com
Supplements
Maia et al. 2025: Probiotics & HRV in hypertensive women
frontiersin.org
Supplements
Badawy et al. 2024: GABA supplementation RCT
tandfonline.com
Supplements
Kimura et al. 2007: L-Theanine & stress
pubmed.ncbi.nlm.nih.gov
Supplements
Raimundo et al. 2025: Beetroot juice in postmenopausal women
doi.org
Lifestyle
Sammito et al. 2024: Factors influencing HRV
doi.org
Lifestyle
Zhang et al. 2025: Sleep deprivation & HRV meta-analysis
doi.org
Lifestyle
Chaitanya et al. 2022: Slow breathing & HRV
doi.org
Lifestyle
Hausswirth et al. 2013: Cryotherapy & HRV
doi.org
Lifestyle
Nesvold et al. 2012: Meditation & HRV
doi.org
Lifestyle
Lehrer & Gevirtz 2014: HRV biofeedback review
pmc.ncbi.nlm.nih.gov
Lifestyle
Park et al. 2010: Forest bathing & HRV
pubmed.ncbi.nlm.nih.gov
Lifestyle
Moro et al. 2023: Intermittent fasting & HRV
pmc.ncbi.nlm.nih.gov
Lifestyle
Pietilä et al. 2018: Alcohol & HRV
doi.org
Lifestyle
Gonzalez et al. 2026: THC & overnight HRV
doi.org
Lifestyle
Gonzalez et al. 2024: Caffeine & HRV recovery
pmc.ncbi.nlm.nih.gov
Lifestyle
Brunt et al. 2025: Sauna & HRV
physoc.onlinelibrary.wiley.com
Lifestyle
Brody & Preut 2003: Sexual activity & HRV
pubmed.ncbi.nlm.nih.gov
Lifestyle
Frontiers Physiol 2025: Altitude & HRV meta-analysis
frontiersin.org
Lifestyle
Stein et al. 2012: Caloric restriction & HRV
pmc.ncbi.nlm.nih.gov
Lifestyle
Young et al. 2019: Mild dehydration & HRV
doi.org
Exercise
Yang et al. 2024: Exercise NMA
29 RCTs
Exercise
Amekran et al. 2024: Exercise training & HRV meta-analysis
doi.org
Exercise
Sharma et al. 2025: Yoga & HRV in students
doi.org
Exercise
Addleman et al. 2024: Overtraining & HRV
doi.org
Nutrition & Micronutrients
Young & Benton 2018: Diet, nutrition & HRV review
doi.org
Nutrition & Micronutrients
Lopresti 2020: Micronutrients & HRV review
doi.org
Demographics
Schmalenberger et al. 2019: Menstrual cycle & HRV meta-analysis
doi.org
Show all 29 sources
From the blog
Show fewer sources
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This content is for informational purposes only and is not medical advice. Always consult a qualified healthcare provider before starting any supplement, exercise program, or lifestyle change.
Data sourced from peer-reviewed studies and meta-analyses. Last updated October 2026.
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