The Push-Up Cardiovascular Capacity Study: A 40 Push-Up Threshold Predicts 96% Lower Heart Disease Risk

Based on the Retrospective Longitudinal Cohort Study

Association Between Push-up Exercise Capacity and Future Cardiovascular Events Among Active Adult Men

Justin Yang et al. JAMA Network Open. 2019.

Reason Behind the Study

By 2019, a substantial body of evidence had firmly established that higher levels of physical fitness are associated with lower risks of cardiovascular disease and improved longevity. Cardiorespiratory fitness, typically measured by maximal oxygen consumption or VO2 max during treadmill testing, had been shown to be a powerful independent predictor of cardiovascular outcomes. However, a critical practical problem remained unsolved. Cardiorespiratory fitness testing requires expensive equipment, trained personnel, significant time, and patient effort to reach maximum exertion. It is not feasible in most primary care settings. Simpler field tests of fitness, such as grip strength or sit to stand tests, had been studied but lacked the dynamic whole body engagement that characterises most physical activities. Justin Yang, Stefanos Kales, and their colleagues at Harvard University and the Indiana University School of Public Health recognised that a fundamental question had not been answered. Could a simple, no cost, easily administered test of muscular endurance, specifically push up capacity, predict future cardiovascular events with sufficient accuracy to be clinically useful? The study population of male firefighters was ideal for this question because occupational physical demands are high, baseline fitness levels vary substantially, and complete follow up for cardiovascular events is feasible within a closed occupational cohort. The study, published in JAMA Network Open in February 2019, directly tested the hypothesis that push up capacity on a single baseline examination would be inversely associated with incident cardiovascular events over a 10 year follow up period.

Goals

The study had a clear primary objective: to evaluate the association between push up capacity measured at a single baseline physical examination and the subsequent incidence of cardiovascular disease events over a 10 year period in a cohort of active adult men. The key innovation was the focus on a simple, office based measure that any clinician could administer in less than two minutes without any equipment. A secondary objective was to compare the strength of association between push up capacity and cardiovascular events with the association between estimated cardiorespiratory fitness from treadmill testing and cardiovascular events. This comparison would determine whether the simple push up test could provide information comparable to the more complex and expensive treadmill test. A tertiary objective was to identify a practical threshold or cut point for push up capacity that could be easily remembered and applied in clinical practice to identify men at increased cardiovascular risk.

Key Eye Opening Findings

The study produced three findings that have significant implications for cardiovascular risk assessment in primary care. First, there was a strong, dose dependent inverse association between push up capacity and incident cardiovascular events. Men who could complete more than 40 push ups at baseline had a 96 percent lower risk of a cardiovascular event over the subsequent 10 years compared to men who could complete fewer than 10 push ups. The incidence rate ratio was 0.04, with a 95 percent confidence interval from 0.01 to 0.36, indicating a reduction in risk that was both clinically massive and statistically significant. Second, this association was not explained by age or body mass index. The analysis adjusted for both potential confounders, and the inverse association remained robust. Third, the protective effect of push up capacity was not limited to the highest performing group. Each incremental increase in push up capacity across the five categories, fewer than 10, 10 to 20, 21 to 30, 31 to 40, and more than 40, was associated with a progressively lower risk of cardiovascular events. The group completing 11 to 20 push ups had a significantly lower risk than the group completing fewer than 10, demonstrating that meaningful benefit begins well before the 40 push up threshold. Strikingly, the association between push up capacity and cardiovascular events was as strong as, or stronger than, the association between estimated cardiorespiratory fitness from treadmill testing and cardiovascular events, suggesting that a 30 second push up test may provide information comparable to a full treadmill stress test.

1. Study in Detail

Design and Participants

The study was a retrospective longitudinal cohort study conducted within a single occupational cohort. Male firefighters aged 18 years or older from 10 fire departments in Indiana underwent periodic physical examinations at a single outpatient clinic between February 2000 and November 2007. These examinations were part of the firefighters routine occupational health surveillance. The cohort was highly specific: all participants were active, employed men with physically demanding jobs. A total of 1,562 participants underwent baseline examination. After excluding those with missing push up data, the final analytic cohort comprised 1,104 men. The mean age of the cohort at baseline was 39.6 years, with a standard deviation of 9.2 years and a range from 21 to 66 years. The mean body mass index, or BMI, was 28.7, with a standard deviation of 4.3, placing the average participant in the overweight category. None of the participants had established cardiovascular disease at baseline. This sample provided 10 years of follow up data through 2010, with a total of 8,601 person years of observation.

Methodology

The study had a straightforward but rigorous design. Each participant underwent a standardised baseline physical examination that included two key fitness assessments.

Push Up Capacity Testing

Push up capacity was measured using a standardised protocol. Participants performed push ups at a cadence of 80 beats per minute, set by a metronome, which corresponds to approximately one push up every 1.5 seconds or 40 push ups per minute. This standardised cadence ensured that participants could not rush through the movement or use momentum to complete more push ups than their true muscular endurance would allow. Push ups were continued until the participant reached exhaustion, could not maintain the required cadence, or demonstrated poor form as judged by the examining clinician. The total number of completed push ups was recorded. Participants were then stratified into five categories based on their push up capacity: fewer than 10, 10 to 20, 21 to 30, 31 to 40, and more than 40 push ups.

Exercise Tolerance Testing

In addition to push up testing, participants underwent treadmill exercise tolerance testing using a modified Bruce protocol. The test continued until participants reached at least 85 percent of their maximal predicted heart rate, requested early termination, or experienced a clinical indication for termination such as chest pain or arrhythmia. Estimated cardiorespiratory fitness, expressed as metabolic equivalents or METs, was derived from treadmill performance. This allowed the researchers to compare the predictive value of push up capacity against the established gold standard of treadmill derived fitness.

Outcome Ascertainment

The primary outcome was incident cardiovascular disease events occurring during the 10 year follow up period through 2010. Cardiovascular events were defined as diagnoses of coronary artery disease, including myocardial infarction and coronary revascularisation procedures such as angioplasty or bypass surgery, as well as other major cardiovascular events including heart failure and sudden cardiac death. Events were ascertained from medical records and occupational health records. A total of 37 cardiovascular events occurred during the follow up period among the 1,104 men with push up data.

Statistical Analysis

Incidence rate ratios, or IRRs, were computed to compare the risk of cardiovascular events across push up categories, using the fewer than 10 push ups category as the reference group. Logistic regression models were used to adjust for potential confounders, specifically age and body mass index. Kaplan Meier survival curves were constructed to visualise the cumulative risk of cardiovascular events over time across the five push up categories. The researchers also calculated incidence rates per 1,000 person years for each category to provide clinically interpretable estimates.

1. Key Findings

The 96 Percent Risk Reduction at 40 Push Ups

The primary finding was unambiguous and striking. Among the 1,104 men followed for 10 years, the incidence rate of cardiovascular events per 1,000 person years was 49.0 in the group completing fewer than 10 push ups. In contrast, the incidence rate was only 3.0 in the group completing more than 40 push ups. This represents a 94 percent lower crude incidence rate. After adjusting for age and body mass index, the incidence rate ratio comparing the more than 40 push up group to the fewer than 10 push up group was 0.04, with a 95 percent confidence interval from 0.01 to 0.36. This adjusted 96 percent risk reduction was highly statistically significant, with a p value for trend across categories of less than 0.001. The Kaplan Meier survival curves diverged progressively over the 10 year follow up, with the highest push up capacity group maintaining near complete freedom from cardiovascular events while the lowest capacity group showed steady accumulation of events.

Dose Response Across All Categories

Importantly, the protective effect was not limited to the elite 40 plus push up group. Each incremental increase in push up capacity was associated with a progressively lower risk of cardiovascular events. Compared to the fewer than 10 push up reference group, the incidence rate ratio for the 10 to 20 push up group was 0.28, with a 95 percent confidence interval from 0.10 to 0.75. This represents a 72 percent reduction in risk for men who could complete just 10 to 20 push ups. The 21 to 30 push up group had an incidence rate ratio of 0.18, with a confidence interval from 0.05 to 0.59, representing an 82 percent reduction. The 31 to 40 push up group had an incidence rate ratio of 0.12, with a confidence interval from 0.02 to 0.58, representing an 88 percent reduction. This clear dose response pattern, with risk decreasing monotonically as push up capacity increased, strongly supports a causal interpretation of the association and indicates that meaningful cardiovascular benefit begins at relatively modest levels of push up capacity.

Comparison With Treadmill Fitness

The study also compared the predictive value of push up capacity with that of estimated cardiorespiratory fitness derived from treadmill exercise tolerance testing. The two measures were significantly correlated, which is expected given that push up capacity reflects overall physical fitness. More importantly, when both measures were entered into the same multivariate model, push up capacity remained a significant predictor of cardiovascular events. The similar incidence rate ratios for cardiovascular events when the cohort was stratified by estimated VO2 max and by push up capacity suggested that the simple push up test provided information comparable to the treadmill test. This finding has substantial practical implications because a push up test takes less than two minutes, requires no equipment, and can be performed in any clinical setting, whereas a treadmill test requires expensive equipment, trained personnel, and at least 20 to 30 minutes per patient.

Limitations of the Study

The study had several important limitations that must be understood before applying the findings. First and most critically, the study cohort consisted exclusively of active adult men who were employed as firefighters. This population is younger, healthier, and more physically active than the general population. The findings may not generalise to women, older adults, sedentary individuals, or those with existing chronic diseases. Second, the total number of cardiovascular events was small, only 37 events across 10 years. While the statistical power was adequate to detect the large observed effect, the confidence intervals around the incidence rate ratios were wide. Third, the study did not have data on important potential confounders including smoking status, alcohol use, family history of cardiovascular disease, or blood pressure and cholesterol levels. Although the analysis adjusted for age and BMI, residual confounding by these unmeasured factors cannot be ruled out. Fourth, the results do not support push up capacity as an independent predictor in the sense of being superior to or replacing traditional risk factors. Rather, push up capacity appears to be a useful integrated measure of functional status that captures the cumulative effect of physical activity, muscular fitness, and overall health. Fifth, the study assessed push up capacity at a single time point and did not account for changes in fitness over the 10 year follow up period. Men who maintained or improved their push up capacity may have had different outcomes than those whose fitness declined.

1. Lessons Learned

Muscular Endurance Is a Clinically Important Marker of Cardiovascular Risk

The most important lesson from this study is that muscular endurance, measured simply by how many push ups a person can perform, provides meaningful information about future cardiovascular risk that is not fully captured by traditional risk factors. This challenges the historical focus on cardiorespiratory fitness as the primary fitness measure for cardiovascular risk prediction. Muscular endurance and cardiorespiratory fitness are correlated but distinct constructs, and both appear to contribute independently to cardiovascular risk. Push up capacity reflects not only upper body strength and endurance but also core stability, neuromuscular coordination, and the ability to sustain a moderate intensity whole body effort.

A Simple Threshold Has Practical Utility

The finding that 40 push ups serves as a useful threshold, with men exceeding this number having a 96 percent lower risk than those completing fewer than 10, provides a memorable and actionable clinical message. However, the dose response data show that any increase from very low capacity is beneficial. Men who can complete only 10 push ups have a 72 percent lower risk than men who cannot complete 10. The message should not be that everyone needs to reach 40 push ups to benefit. Rather, the message is that very low push up capacity, fewer than 10, identifies a high risk group, and any improvement from that baseline is associated with substantial risk reduction.

The Firefighter Cohort Provides a Valid Model for Working Age Men

While the exclusive focus on male firefighters limits generalisability, it also provides a valid model for working age men in physically demanding occupations. Firefighters are required to maintain adequate fitness to perform their jobs safely. The study demonstrates that even within a relatively fit occupational cohort, wide variation in push up capacity exists and strongly predicts cardiovascular outcomes. For employers of workers in physically demanding jobs, such as law enforcement, military, construction, and emergency medical services, this study provides evidence that simple fitness testing can identify individuals at elevated cardiovascular risk who might benefit from targeted intervention.

Functional Status Testing Is Underused in Primary Care

The study highlights a broader problem in clinical practice. Primary care visits focus heavily on measuring traditional risk factors, blood pressure, cholesterol, blood glucose, and smoking status, while rarely including any objective measure of functional status or physical fitness. This is paradoxical because physical fitness is a powerful predictor of outcomes, and functional status is what patients experience in their daily lives. The push up test offers a potential solution to this gap because it is no cost, fast, requires no equipment, and provides an objective, reproducible measure that patients understand intuitively.

1. How This Research Can Help Humanity

Providing a No Cost Cardiovascular Risk Assessment Tool

For clinicians in resource limited settings, including rural clinics, community health centres, and low and middle income countries where treadmill testing is unavailable, the push up test offers a practical alternative for assessing functional status and cardiovascular risk. A clinician can ask a patient to perform as many push ups as possible at a steady cadence. Completing fewer than 10 push ups identifies a high risk patient who may benefit from more intensive lifestyle intervention or further diagnostic evaluation. Completing more than 40 push ups provides reassurance of good functional status.

Encouraging Strength Training for Cardiovascular Health

Public health messaging about physical activity for cardiovascular health has historically emphasised aerobic activities such as walking, running, and cycling. Strength training has been recommended primarily for musculoskeletal health, fall prevention, and metabolic health. This study adds to a growing body of evidence that muscular strength and endurance directly predict cardiovascular outcomes. Public health guidelines should strengthen their recommendations for regular resistance training, including push ups, as a component of cardiovascular disease prevention.

Motivating Behaviour Change Through Simple Benchmarks

Many individuals find abstract fitness goals, such as improving VO2 max by 3.5 mL per kg per minute, difficult to understand and motivate towards. In contrast, the goal of completing 10, 20, or 40 push ups is concrete, easily understood, and can be tested at home without special equipment. This study provides evidence based benchmarks that individuals can use to assess their own fitness and track progress. A man who can only complete 5 push ups today has a clear and motivating goal of reaching 10, knowing that doing so is associated with a 72 percent lower cardiovascular risk than remaining below 10.

Informing Occupational Health Screening for First Responders

Firefighters, police officers, and emergency medical personnel face high physical demands and elevated cardiovascular risk. Sudden cardiac death is a leading cause of on duty death among firefighters. This study provides evidence that push up testing, already used in many fire department fitness assessments, is not merely a measure of job readiness but a predictor of long term cardiovascular health. Fire departments can use push up capacity as one component of a comprehensive cardiovascular risk reduction programme, identifying firefighters with very low push up capacity for more intensive risk factor management.

1. Final Summary

Most Important Takeaways

1. High push up capacity is associated with dramatically lower cardiovascular risk. Men who could complete more than 40 push ups at baseline had a 96 percent lower risk of a cardiovascular event over the subsequent 10 years compared to men who could complete fewer than 10 push ups. The adjusted incidence rate ratio was 0.04, with a 95 percent confidence interval from 0.01 to 0.36.

2. The protective effect follows a clear dose response pattern. Compared to the fewer than 10 push up reference group, the 10 to 20 push up group had a 72 percent risk reduction, the 21 to 30 push up group had an 82 percent reduction, the 31 to 40 push up group had an 88 percent reduction, and the more than 40 push up group had a 96 percent reduction. Each incremental increase in push up capacity was associated with lower risk.

3. Meaningful benefit begins at modest levels of push up capacity. Men who could complete only 10 to 20 push ups had a substantially lower risk than those who could complete fewer than 10. The threshold for high risk is fewer than 10 push ups, not failure to reach 40.

4. Push up capacity provides information comparable to treadmill testing. The association between push up capacity and cardiovascular events was as strong as the association between estimated cardiorespiratory fitness from treadmill testing and cardiovascular events, suggesting that a 30 second push up test may be a practical substitute for more complex fitness testing in many clinical settings.

5. The study population was limited to active adult male firefighters. The findings may not generalise to women, older adults, sedentary individuals, or those with existing chronic diseases. Larger studies in more diverse populations are needed before push up testing can be recommended for the general population.

6. Cardiovascular disease is multifactorial, and push up capacity is not an independent predictor in the sense of replacing traditional risk factors. Rather, push up capacity serves as an integrated marker of functional status that captures the cumulative effects of physical activity, muscular fitness, body composition, and overall health. Traditional risk factors including blood pressure, cholesterol, smoking, and family history remain essential components of cardiovascular risk assessment.

Action Points

For Primary Care Clinicians

Consider incorporating a simple push up test into periodic health examinations for male patients, particularly those in middle age or those with sedentary occupations. The test takes less than two minutes, requires no equipment, and provides objective information about functional status that patients understand intuitively. Use the threshold of fewer than 10 push ups to identify patients at potentially elevated cardiovascular risk who may benefit from more intensive lifestyle counselling or further risk factor assessment. Explain to patients that improving from fewer than 10 push ups to 10 to 20 push ups is associated with a 72 percent reduction in cardiovascular risk, a message that many find motivating.

For Individuals Seeking to Reduce Cardiovascular Risk

Do not rely solely on walking or aerobic exercise for cardiovascular health. Regular resistance training that builds muscular endurance, including push ups, is associated with substantially lower cardiovascular risk independent of aerobic fitness. If you cannot complete 10 push ups, start with knee push ups or incline push ups against a wall or counter. Gradually progress as strength improves. The goal is not necessarily to reach 40 push ups, although that is excellent. The goal is to move out of the highest risk category, fewer than 10 push ups, into a higher category. Any increase in push up capacity is associated with meaningful risk reduction.

For Occupational Health Programmes in Physically Demanding Jobs

Consider incorporating push up testing into annual fitness assessments for firefighters, police officers, military personnel, and other workers in physically demanding occupations. Use the threshold of fewer than 10 push ups to identify individuals who may require additional fitness training or more intensive cardiovascular risk factor management. Recognise that the study provides evidence that push up capacity is not merely a measure of job readiness but a predictor of long term cardiovascular health outcomes.

For Public Health Authorities

Update physical activity guidelines to more strongly emphasise resistance training for cardiovascular health. Current guidelines recommend muscle strengthening activities on two or more days per week but present these recommendations as ancillary to aerobic activity guidelines. The evidence from this study, together with supporting literature, suggests that muscular endurance is a powerful independent predictor of cardiovascular outcomes and deserves emphasis equal to aerobic fitness in public health messaging.

For Researchers

The study opens several important questions for future investigation. First, does the association between push up capacity and cardiovascular events generalise to women? No large study has yet examined this question in a female cohort. Second, what is the association in older adults, particularly those over age 65, among whom cardiovascular event rates are higher and push up capacity is generally lower? Third, does improving push up capacity through training reduce cardiovascular risk, or is push up capacity merely a marker of underlying fitness that cannot be modified independently? A randomised controlled trial of a push up training programme with cardiovascular outcomes would be required to answer this question definitively. Fourth, can the push up test be validated in diverse racial and ethnic populations, including those with different baseline fitness levels and different cardiovascular risk profiles?

Recommended Follow Up Study

The Push Up Training Cardiovascular Outcomes Trial

The Yang study established a strong association between baseline push up capacity and future cardiovascular events but could not determine whether improving push up capacity through training would reduce risk. The logical next step is a randomised controlled trial of a push up training intervention in sedentary men with low baseline push up capacity, defined as fewer than 10 push ups. A three arm parallel group trial would compare a control condition of usual care without exercise guidance to a home based push up training programme using a progressive protocol, and to a standard aerobic exercise programme of brisk walking. The push up training group would perform three sessions per week, gradually increasing repetitions over 12 months. The primary outcome would be change in estimated 10 year cardiovascular risk using the Pooled Cohort Equations. Secondary outcomes would include blood pressure, cholesterol, fasting glucose, and directly measured push up capacity. This trial would answer whether the association observed by Yang is causal and modifiable, or whether push up capacity is merely a non modifiable marker of underlying cardiovascular risk.

List of Other Related and Connected Studies

The Harvard Alumni Study Physical Activity and Mortality (1995, New England Journal of Medicine)

This landmark prospective cohort study of over 17,000 male Harvard alumni found that total energy expenditure from physical activity was inversely associated with all cause mortality. The study established the foundation for modern physical activity guidelines by demonstrating a dose response relationship between activity and longevity. The Yang push up study extends this by focusing specifically on muscular endurance rather than total energy expenditure or aerobic activity.

The Cooper Center Longitudinal Study Fitness and Mortality (2002, Medicine and Science in Sports and Exercise)

This large prospective study of over 40,000 men demonstrated that cardiorespiratory fitness measured by treadmill testing is a powerful predictor of cardiovascular and all cause mortality, independent of traditional risk factors. The Yang study parallels this finding but substitutes a simple push up test for the complex treadmill test.

The ORFIT Study Muscular Strength and Mortality (2008, British Medical Journal)

This study of over 8,000 men found that muscular strength, measured by grip strength and leg extension strength, was inversely associated with all cause mortality and cardiovascular mortality. The Yang study focuses on muscular endurance rather than maximal strength, demonstrating that the ability to perform repeated submaximal contractions is also a powerful predictor.

The STRRIDE Study Resistance Training and Metabolic Health (2009, Journal of Applied Physiology)

This randomised controlled trial found that resistance training improves insulin sensitivity and reduces metabolic syndrome components even in the absence of weight loss. The Yang study provides the epidemiological counterpart, showing that muscular endurance measured in the real world predicts hard cardiovascular outcomes.

The HUNT Study Fitness and Cardiovascular Disease in Women (2015, European Heart Journal)

This large prospective study of over 20,000 women found that cardiorespiratory fitness was inversely associated with cardiovascular events, but the association was weaker in women than in men. This highlights the critical need for the Yang study to be replicated in a female cohort, as the findings may not generalise across sexes.

The UK Biobank Physical Activity and Cardiovascular Disease Study (2017, JACC)

This study of over 500,000 participants found that both aerobic and strength based physical activities were independently associated with lower cardiovascular risk. The Yang study adds precision by quantifying muscular endurance with a specific, reproducible test rather than self reported strength training frequency.

The Prospective Urban Rural Epidemiology or PURE Study (2017, The Lancet)

This large international cohort study found that grip strength was a stronger predictor of cardiovascular and all cause mortality than systolic blood pressure. The Yang study suggests that a whole body muscular endurance test, the push up, may be an even better predictor than the isolated grip strength measure.