Researchers studied how stretching affects the heart and nervous system in young adults. They had 24 healthy people do passive forearm stretches (where someone else gently stretches your arm) while measuring their heart rate, blood pressure, and how well their heart responds to changes. They found that stretching increased blood pressure during the stretch, but afterward, the heart’s relaxation system became more active. Interestingly, men’s blood pressure went up more than women’s during stretching, but both sexes showed similar improvements in heart relaxation afterward. This suggests that gentle stretching might help train your heart’s natural calming system.

The Quick Take

  • What they studied: Whether passive stretching (having someone gently stretch your muscles) affects how your heart responds and relaxes, and if men and women respond differently
  • Who participated: 24 healthy young adults (average age 23 years old) - 13 men and 11 women - with no known health problems
  • Key finding: Passive forearm stretching increased blood pressure during the stretch (more so in men), but afterward, the heart’s relaxation system became significantly more active in both sexes. The heart also became better at responding to blood pressure changes after stretching.
  • What it means for you: Gentle stretching might help train your heart’s natural relaxation system, which could be beneficial for heart health. However, this is early research in young, healthy people, so more studies are needed before making stretching recommendations for everyone.

The Research Details

This study had 24 young, healthy adults come to the lab on two separate days. On one day, they rested quietly for 10 minutes while lying down. On the other day, they did the same rest period but then completed five rounds of passive forearm stretching (where a researcher gently stretched their forearm for 1 minute, followed by 15 seconds of rest). Throughout both visits, researchers continuously measured the participants’ heart rate using an ECG machine (the same device used in hospitals), blood pressure using a finger sensor and arm cuff, and how well their heart responded to blood pressure changes.

The researchers used a special method called the ‘sequence method’ to measure something called cardiac baroreflex sensitivity (cBRS). This is basically how well your heart’s nervous system can sense and respond to changes in blood pressure. They measured this at rest, during stretching, immediately after, and then again 15 and 30 minutes later.

The study was designed to compare what happened on the stretching day versus the rest day, and to look for differences between men and women.

Understanding how stretching affects the heart’s nervous system is important because the nervous system controls many automatic functions like heart rate and blood pressure. If stretching can improve how well the heart responds to these changes, it might be a simple way to support heart health. Looking at sex differences is important because men and women sometimes respond differently to exercise and stretching, so recommendations might need to be tailored.

This study was published in a respected scientific journal focused on applied physiology. The researchers used objective, scientific measurements (ECG, blood pressure monitors) rather than relying on what people reported. They tested people on separate days and randomized the order of conditions to reduce bias. However, the sample size was relatively small (24 people), all participants were young and healthy, and the study was only done once, so results need to be confirmed by other researchers before drawing firm conclusions.

What the Results Show

When participants did the passive stretching, their mean blood pressure increased significantly compared to the rest day. Men experienced a larger increase (about 9 mmHg) compared to women (about 4 mmHg), which was a statistically significant difference. This makes sense because men typically have different cardiovascular responses to physical stress than women.

After the stretching ended, something interesting happened: the vagal modulation (a measure of how active the relaxation part of the nervous system is) increased by about 11 milliseconds. This suggests that stretching activated the parasympathetic nervous system, which is the part that helps your body relax and recover.

The heart’s ability to respond to rising blood pressure (called cBRS-Up) improved after stretching by about 3 ms/mmHg. This means the heart became better at sensing and responding to increases in blood pressure. However, the heart’s response to falling blood pressure (cBRS-Down) didn’t change significantly.

Importantly, while men and women showed different blood pressure responses during stretching, both sexes showed similar improvements in heart relaxation and responsiveness during recovery.

The study found that the improvements in vagal modulation and heart responsiveness persisted during the 15 and 30-minute recovery periods, suggesting that the effects of stretching lasted beyond the immediate post-stretch period. The fact that cBRS-Up improved but cBRS-Down didn’t suggests that stretching may specifically enhance the heart’s ability to handle increases in blood pressure rather than decreases.

Previous research has suggested that stretching might improve vagal activity (the relaxation part of the nervous system), but this study is among the first to carefully measure both blood pressure responses and heart baroreflex sensitivity during and after passive stretching. The finding that men show greater blood pressure increases aligns with existing research showing sex differences in cardiovascular responses to physical stress. The improvement in vagal modulation supports earlier suggestions that stretching may enhance the body’s relaxation response.

The study only included 24 young, healthy adults (average age 23), so results may not apply to older people, people with health conditions, or those who are less fit. The study only tested passive stretching (where someone else does the stretching), so it’s unclear if active stretching (where you stretch yourself) would have the same effects. The study was conducted only once, so we need other researchers to repeat it to confirm the findings. Additionally, the study didn’t look at whether these changes actually improve long-term heart health or reduce disease risk.

The Bottom Line

Based on this research, passive stretching appears to activate the heart’s relaxation system and improve how the heart responds to blood pressure changes in young, healthy adults. However, this is early-stage research, so we cannot yet make strong recommendations. If you’re young and healthy, gentle stretching as part of a regular exercise routine is generally safe and may offer these cardiovascular benefits. If you have heart disease, high blood pressure, or other health conditions, talk to your doctor before starting a new stretching routine.

Young, healthy adults interested in optimizing their cardiovascular health through simple, low-cost interventions should find this interesting. People interested in how the nervous system controls heart function may also benefit from understanding these findings. However, people with existing heart conditions, those taking heart medications, or older adults should consult their healthcare provider before making changes based on this research, as the study only included healthy young people.

Based on this study, improvements in heart relaxation and responsiveness appeared within 15-30 minutes after stretching. However, it’s unclear how long these benefits last or whether regular stretching over weeks or months would provide additional benefits. More research is needed to understand the long-term effects of regular stretching on heart health.

Want to Apply This Research?

  • Track daily passive stretching sessions (duration and which muscle groups) alongside resting heart rate measurements taken at the same time each morning. Over 4-8 weeks, look for trends in whether resting heart rate decreases or becomes more variable, which could indicate improved heart nervous system function.
  • Add 5 minutes of passive stretching (or partner-assisted stretching) to your daily routine, ideally in the evening. This could be done with a partner, using a stretching strap, or with a physical therapist. Log each session in the app and note how you feel during recovery.
  • Measure resting heart rate variability (if your app or device supports it) weekly, as this reflects how well your heart’s relaxation system is working. Compare measurements before and after implementing a regular stretching routine over 8-12 weeks. Also track subjective feelings of relaxation or stress levels to see if stretching correlates with improved recovery and relaxation.

This research is preliminary and was conducted only in young, healthy adults. The findings do not constitute medical advice and should not be used to diagnose, treat, or prevent any disease. If you have heart disease, high blood pressure, take heart medications, or have any medical conditions, consult your healthcare provider before starting a new stretching routine or making changes to your exercise habits. Individual responses to stretching may vary, and this study does not prove that stretching prevents heart disease or provides long-term health benefits.