4 Unexpected Health Metrics That May Predict Longevity

The idea of living a longer life is alluring to just about anyone—assuming it’s a healthy one, that is. Unfortunately, at 78.6, the average life expectancy in the United States is lower now than a decade ago. The causes of this decline (as well as the U.S.’s comparatively low average life expectancy), include poor lifestyle habits and higher rates of heart and chronic diseases, according to the American Medical Association. But just because average lifespan is currently lagging doesn’t mean you can’t extend your years.

Whether it’s because you want to live long enough to enjoy grandchildren, travel the world post-retirement, or see the first astronaut saunter around Mars, there’s plenty you can do to support your longevity (from prioritizing certain foods and supplements to keeping your blood sugar balanced to trying out practices like ice baths and earthing). 

In addition to adopting a longevity-friendly lifestyle, those seeking to extend (and enjoy more of!) their golden years might also want to monitor a few specific health metrics. Ahead, learn about four health and fitness data points that can tell you a tremendous amount about your body and how it’s aging. 

• ABOUT OUR EXPERTS: Sharon Gam, Ph.D., C.S.C.S., is an exercise physiologist and certified strength and conditioning coach. Jake Harcoff, C.S.C.S., is a certified strength and conditioning specialist and the head coach and owner of AIM Athletic.

1. Resting Heart Rate 

As far as health metrics go, resting heart rate is pretty straightforward—and super-relevant for longevity. Your resting heart rate is a measure of how many times your heart beats per minute when you are (you guessed it) at rest, explains exercise physiologist and certified strength and conditioning coach Sharon Gam, Ph.D., C.S.C.S. 

“Generally, a lower resting heart rate indicates a healthier and more efficient cardiovascular system,” she says. “It indicates that your heart doesn’t have to work as hard to deliver blood throughout your body, which is a good thing.” Research has even linked a lower resting heart rate to a longer lifespan, and a higher resting heart rate to disease and a shorter lifespan, according to Gam. 

One 2021 review published in Cardiorespiratory Physiotherapy, Critical Care and Rehabilitation, for example, reported that in healthy people—as well as in patients with certain illnesses, such as heart failure, chronic obstructive pulmonary disease, and lung disease—lower resting heart rate values ​​provide greater longevity. Meanwhile, an August 2024 study published in Scientific Reports found that even a slight increase in resting heart rate led to statistically significant increases in mortality risk. 

Read More: 6 Ways You Could Be Unknowingly Putting Your Heart Health At Risk

Resting heart rate is one of the easiest and most accessible health metrics to track, as even rudimentary smartwatches provide decently accurate measurements. You can also find your pulse in your wrist or neck and count how many times it thumps within a 60-second timespan. A healthy resting heart rate for adults ranges from 60 to 100 beats per minute, according to the American Heart Association. That said, well-trained (a.k.a. physically fit) individuals may have resting heart rates in the 40s or 50s. 

If you have a high resting heart rate, Gam suggests chatting with your healthcare provider. “It’s important to check with your doctor if your heart rate is a lot lower or higher than average, as medications and certain medical conditions can affect resting heart rate,” she says. From there, Gam suggests implementing a doctor-approved fitness regime, if you don’t have one already. “Exercising will lower your resting heart rate and supports the overall health of your entire body, which can decrease your chances of chronic disease and premature death,” she explains. 

2. Heart Rate Variability 

Most smartwatches track heart rate variability (HRV), so if your wrist is decked out with a mini-computer, you probably already have access to this measurement. “Heart rate variability is how much variance there is in the time between each heartbeat,” says Gam. As it turns out, “having an average resting heart rate of 60 beats per minute, for example, doesn’t mean that each heartbeat is exactly one second apart,” she explains. Rather, the time between each beat varies. “Your heart might beat after one second, and then again after 1.2 seconds, and then after 0.7 seconds, and then 0.9 seconds, and so on.”

While a lower resting heart rate is generally considered healthier than a higher one, the inverse is true for heart rate variability. A higher HRV indicates an ability to transition seamlessly between work and rest, according to certified strength and conditioning specialist Jake Harcoff, C.S.C.S., head coach and owner of AIM Athletic. “It suggests you can recover from stress efficiently and signals that you have good cardiovascular health and a more regulated nervous system,” he says. On the flip side, a lower HRV suggests that your body is not resilient to stress and struggles to handle changing and challenging situations. 

While an HRV does not directly determine longevity, it does give useful insights into overall health that can impact longevity. Specifically, it signals both a healthy heart and a healthy central nervous system (CNS), which are prerequisites for a long life, Harcoff says. As such, the researchers behind one November 2024 study published in Ageing Research Reviews report that heart rate variability is an “affordable, non-invasive, and cost-effective”  biomarker for aging, as it gives insights into systemic inflammation and nervous system function. 

Here’s where this one gets tricky: “Heart rate variability varies a lot between individuals, and there aren’t guidelines for the exact range that would be considered ‘good’ or ‘bad,’ ‘healthy,’ or ‘less healthy,’” says Gam. She suggests against aiming for a specific number and instead monitoring your heart rate variability over time. “You want to get an average baseline over a week and then monitor it regularly to see what happens,” she explains. “If your heart rate variability increases, your nervous system is probably getting healthier. If it decreases, you might be under a lot of stress and could benefit from an intervention.” 

If you don’t have a device that tracks your heart rate variability, you can still support a healthy heart and maintain strong heart rate variability through regular cardiovascular training, strength training, proper nutrition, stress relief practices, and quality sleep. Cardio activities like walking or cycling improve heart health, while strength training helps build muscle and improves metabolism and overall cardiovascular and nervous system function. Meanwhile, “proper nutrition provides the nutrients your body needs to reduce inflammation and support heart health, while managing stress helps keep the nervous system in balance, preventing prolonged stress that will be reflected in a low HRV,” Harcoff says. 

3. VO2 Max

The fact that heart disease is the leading cause of death for American adults highlights the importance of tracking heart health in any quest for longevity. That’s why VO2 max, a sophisticated measure of cardiorespiratory health and fitness, is another metric worth looking into.

VO2 max, a.k.a. maximal oxygen consumption, measures the maximum amount of oxygen a person can absorb and use during exercise. “It reflects the body’s ability to deliver oxygen to muscles to transform into energy during physical activity,” Harcoff explains. The higher your VO2 max, the better your body is at taking oxygen from the air and delivering it to your muscles for fuel, which indicates greater cardiovascular capacity and fitness level. “A higher VO2 max is linked to better overall health and lower all-cause mortality, especially as we age,” he says. 

In fact, “research has even shown that low VO2 max after age 45 is strongly linked to higher all-cause mortality, making it essential to keep that score in check,” says Harcoff. Indeed, one study of nearly 1,500 middle-aged men published in the European Journal of Preventive Cardiology reports that low aerobic capacity is associated with increased mortality rates, even after traditional risk factors (like smoking, high blood pressure, and serum cholesterol levels) were taken into account. Meanwhile, a study published in Cardiology found that individuals who increased their VO2 max from below-average to average or above-average levels through regular exercise saw a significant reduction in mortality over 10 years. 

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Unfortunately, while some high-end fitness trackers estimate your VO2 max, obtaining accurate data about it can be tricky and expensive, says Gam. Typically, testing involves performing a cardiopulmonary exercise test at a lab or medical facility with a souped-up machine made just for the task.

That said, even if you don’t know your exact VO2 max, acting as if you’re trying to increase yours will pay dividends, according to Gam. “Intervening to increase your VO2max through exercise can make you healthier and less likely to get a chronic disease or die prematurely,” she says. It’s pretty straightforward, too! At a minimum, start by hitting the CDC’s recommendation of 150 minutes of moderate-intensity physical activity per week. Once that’s routine, find ways to push yourself that you enjoy, whether it’s by taking group fitness classes, training for a race or competition, or hiking more challenging trails.

4. Grip Strength 

Solid grip strength translates into a powerful handshake—and that’s not all. As it turns out, how much force you can exert with your hands is a “surprisingly strong indicator of overall health and longevity,” says Harcoff. In fact, one 2022 review of 48 studies published in Aging Research Reviews concluded that the evidence linking lower grip strength with higher all-cause, cancer, and cardiovascular-related mortality risk is strong. 

Important to clarify here: “It’s not that a strong grip alone increases life span,” says Gam. Rather, grip strength reliably reflects overall muscular strength, which is directly connected with longevity, she says. “Weak grip is often a sign of reduced muscle mass and functional ability, leading to decreased activity and poorer health as we age,” adds Harcoff. 

The reason grip strength is used as a stand-in for overall strength in research? It’s simply much easier to measure! “It’s much more difficult and time-consuming to test the strength of different muscle groups than to administer simple grip-strength tests,” says Gam. (Measuring grip strength only requires a dynamometer, a squeezable handheld available for less than $25 in most sports stores.)

“Being strong means that you have healthy muscle mass and that your nervous system is working adequately, both of which indicate that your body is probably functioning well overall—and if your body is functioning well, you’re more likely to avoid disease and live longer,” says Gam.

Having ample muscle mass suggests you regularly use your muscles through resistance training or other physical activities (like manual labor, active hobbies, etc.). This matters because “physical activity level is also a predictor of longevity,” Gam explains. In fact, one review published in the Journal of Aging Research linked regular physical activity with an increase in life expectancy of up to 6.9 years. 

Further, muscle-strengthening activities support the health of your central nervous system, which allows some muscles to contract while others relax and keeps you balanced and coordinated while you exercise, according to Gam. Since the CNS is the hub of the body that manages your response to internal and external information (including all manner of physiological processes and stress responses), keeping it balanced and effective is certainly important for living a long, healthy life. In fact, a recent study published in The Journal of Physiological Sciences found that the CNS significantly impacts aging and longevity in mammals. 

Since the value of grip strength here is its reflection of your overall strength, your move isn’t to get a grip trainer and start squeezing away day and night. Instead, Gam suggests adding weight training into your routine if it’s not already a priority. The CDC recommends a minimum of two muscle-strengthening activities per week. A fitness professional can point you toward a strength regime that is best for you based on your age, overall health, current activity level, and objectives.