ABI Testing in Athletes: When High Performers Have Hidden PAD

The Marathon Runner Who Couldn’t Finish the Race—And It Wasn’t Training

Sarah had run six marathons over the past decade. At 52, she maintained a rigorous training schedule, logging 40 miles per week without fail. But during her seventh marathon, something changed. At mile 18, her left calf began cramping with an intensity she’d never experienced. She pushed through—athletes always do—but had to walk the final miles.

“I thought I hadn’t hydrated enough,” she later told her sports medicine physician. “Or maybe I needed new shoes.”

It took three months, two physical therapists, and a persistent primary care doctor to discover the truth: Sarah had peripheral artery disease (PAD). A condition she associated with “elderly, sedentary smokers”—not endurance athletes like herself.

Sarah’s story isn’t unique. It’s a cautionary tale about a hidden population of PAD patients that clinicians rarely consider: high-performing athletes.

How Do Athletes Get PAD When They Don’t Smoke or Live Sedentary Lives?

It’s the question every athletic PAD patient asks: “How is this possible? I run marathons. I don’t smoke. I’m not overweight.”

The answer challenges our assumptions about who gets vascular disease—and why.

The Hidden Risk Factors Athletes Carry

While smoking and sedentary lifestyle are major PAD risk factors, they’re far from the only ones. Athletes can harbor serious cardiovascular risk factors that fly under the radar precisely because their fitness level creates a false sense of invulnerability:

Undiagnosed or undertreated hypertension: Many athletes have higher blood pressure than they realize. Some develop exercise-induced hypertension that doesn’t show up in a resting office visit. Others have mild elevation that’s dismissed as “not that bad for someone your age.” But years of even moderately elevated blood pressure damages arterial walls, setting the stage for atherosclerosis.

Silent hyperlipidemia: You can run 40 miles a week and still have genetic familial hyperlipidemia. Exercise improves cholesterol profiles, but it doesn’t override genetic predisposition. Some athletes have elevated LDL or low HDL despite excellent fitness, particularly if they’ve never had comprehensive lipid panels including particle size and apolipoprotein B.

Family history: Cardiovascular disease runs in families. An athlete with a parent who had early heart attack or stroke carries that same genetic risk, even if their lifestyle differs dramatically. Many athletes don’t connect their parent’s cardiovascular events to their own risk—after all, “my dad was sedentary and overweight; I’m nothing like him.”

Unrecognized diabetes or prediabetes: Type 2 diabetes isn’t exclusive to sedentary populations. Athletes can develop insulin resistance, particularly if they have genetic predisposition, despite regular exercise. Many never get screened because clinicians assume their active lifestyle rules out metabolic disease.

Chronic inflammation: While exercise is generally anti-inflammatory, overtraining, inadequate recovery, poor sleep, or undiagnosed autoimmune conditions can create chronic systemic inflammation that accelerates atherosclerosis.

Dietary factors: Not all athletes eat optimally. Some consume high amounts of saturated fats, processed foods, or have poor nutritional balance despite high activity levels. Others restrict calories excessively, creating metabolic stress.

Why Athletes’ PAD Often Looks Different

When athletes do develop PAD, the disease often manifests differently than in traditional patients:

It’s masked by superior physiology: Athletes develop robust collateral circulation and exceptional cardiovascular efficiency. Their bodies compensate for arterial narrowing far better than sedentary individuals, meaning disease must progress further before symptoms break through. A 70% blockage might cause claudication at one block in a sedentary patient but only at mile 15 in a marathon runner.

It’s dismissed as training issues: The first symptoms—leg cramping during exertion—sound identical to overtraining, dehydration, or electrolyte imbalance. Athletes and their providers attribute symptoms to benign training variables rather than vascular pathology. By the time the pattern becomes clear, disease has often progressed significantly.

It appears suddenly: Because athletes push their cardiovascular systems to extreme demands, they may have no symptoms during normal activity but hit a wall during intense exercise. A blockage that reduces blood flow by 50% might be adequate for walking, adequate for jogging, but catastrophically insufficient for marathon pace. The athlete experiences this as sudden-onset problems, not gradual decline.

It’s just as dangerous: Here’s what doesn’t change: PAD in athletes indicates the same systemic atherosclerosis and cardiovascular risk as PAD in sedentary smokers. The arteries in the legs are a window into arteries throughout the body, including those supplying the heart and brain. An athletic 52-year-old with PAD faces the same 4-5 times increased risk of heart attack and stroke as a sedentary 70-year-old with PAD.

The Bottom Line

Athletes get PAD because cardiovascular disease is multifactorial, and exercise—while powerfully protective—doesn’t provide complete immunity. Genetics, undiagnosed risk factors, and years of cumulative arterial damage can occur even in highly active individuals.

The critical point: PAD in an athlete is just as serious as PAD in a sedentary smoker, but it’s far less likely to be suspected, tested for, or diagnosed early. That diagnostic delay can have devastating consequences—not just for athletic performance, but for life-threatening cardiovascular events.

Why Athletes Fly Under the PAD Radar

Peripheral artery disease affects an estimated 18 million Americans, yet remains dramatically underdiagnosed across all populations. In athletes, however, the underdiagnosis problem reaches an entirely different level. Several factors conspire to keep athletic PAD patients hidden:

1. The Symptom Masquerade

Classic PAD symptoms—leg pain with exertion that resolves with rest—sound remarkably similar to countless benign athletic conditions. Muscle strain, overtraining, delayed onset muscle soreness, or simple fatigue all present with exertional leg discomfort. The critical difference? PAD symptoms follow a predictable pattern tied to ischemia, consistently occurring at the same exercise intensity and relieving within minutes of rest.

But athletes often dismiss early symptoms as “part of training,” adjusting their pace or routine to compensate rather than seeking medical attention.

2. Superior Compensation Mechanisms

Athletes develop extraordinary cardiovascular efficiency and collateral circulation that can mask reduced blood flow longer than sedentary individuals. Their bodies adapt, rerouting blood through smaller vessels and maximizing oxygen extraction from available blood supply. This remarkable physiology is both blessing and curse—it allows them to function at high levels despite compromised arterial flow, delaying diagnosis until disease progresses significantly.

3. Exceptionally High Pain Tolerance

Endurance athletes routinely train through discomfort. The line between “good pain” (training adaptation) and “bad pain” (pathology) becomes blurred when you’re accustomed to pushing your body to its limits. What would send a sedentary patient to the doctor barely registers as concerning to someone who regularly runs until exhaustion.

4. The Age-Risk Disconnect

Most clinicians don’t consider PAD screening in active 45-65 year-olds who appear healthy, exercise regularly, and lack obvious risk factors. Yet this demographic can harbor silent disease, particularly if they have undiagnosed hypertension, hyperlipidemia, or a family history of cardiovascular disease. Their athletic status creates a cognitive bias: “They can’t have PAD—they just ran a half-marathon.”

When Exercise Becomes the Diagnostic Clue

The key to identifying PAD in athletes lies in recognizing exercise-induced symptom patterns that don’t fit typical athletic injuries:

Red Flag Symptoms:

• Cramping or aching that occurs at predictable distances or intensities
• Symptoms that resolve within 2-5 minutes of stopping exercise (not 30-60 minutes like muscle fatigue)
• Bilateral symptoms (though unilateral is possible)
• Progressive reduction in exercise capacity despite consistent training
• Cramping in calves, thighs, or buttocks—not just one isolated area
• Symptoms that worsen with incline or speed increase

Differential Diagnosis Challenges:

Athletes presenting with exertional leg pain create complex clinical pictures. Key differentials include:

• Chronic exertional compartment syndrome (CECS): Unlike PAD, compartment syndrome causes tightness and pressure sensation, often with numbness, and takes 15-30 minutes to resolve after stopping exercise
• Popliteal artery entrapment syndrome: Occurs in younger athletes, often runners and cyclists, with symptoms similar to PAD but caused by anatomical compression rather than atherosclerosis
• Muscle strain or tendinopathy: Pain persists during rest, worsens with specific movements, and has localized tenderness on examination
• Nerve compression: Accompanied by numbness, tingling, or radiating pain patterns

The simplest distinguishing tool? Pulse examination and ankle-brachial index (ABI) testing.

The Diagnostic Solution: Simple, Fast, Definitive

When athletes present with concerning exertional leg symptoms, ABI testing provides immediate clarity. The test is non-invasive, requires no special preparation, and delivers objective data within minutes.

Traditional ABI testing

requires manual Doppler examination of bilateral brachial, dorsalis pedis, and posterior tibial pulses—a time-intensive process requiring skilled technique. For busy sports medicine practices or primary care clinics, this creates a barrier to routine screening.

This is where simpleABI-Q transforms the diagnostic workflow.

The simpleABI-Q rapid-test system is purpose-built for busy practices that need fast, accurate PAD screening without the complexity of traditional methods. Using PVR waveforms and proprietary software algorithms, simpleABI-Q delivers accurate results in just 1-2 minutes—without requiring Doppler skills or specialized vascular training.

For sports medicine and primary care clinics evaluating athletes, this speed matters. The entire exam can be completed between appointments, fitting seamlessly into packed schedules without disrupting patient flow. Push-button operation means any medical assistant can perform the test confidently, and the system remains accurate even in patients with calcified arteries—a critical advantage for diabetic athletes or those with undiagnosed metabolic conditions.

For athletes, this means:

• Lightning-fast screening (1-2 minutes) that doesn’t disrupt training schedules
• No Doppler skills required, making testing accessible in any clinic setting
• Objective data that differentiates vascular disease from musculoskeletal conditions
• Accurate results even with arterial calcification
• Immediate referral pathways when abnormal results demand vascular consultation
• Optional exercise protocol capability to assess symptoms under real-world conditions

The simpleABI-Q’s portability also allows for on-site screening at athletic events, training facilities, or anywhere early detection could save an athlete’s career—or life.

The Bigger Picture: PAD as a Cardiovascular Warning

Perhaps most critically, discovering PAD in an athletic patient reveals systemic cardiovascular risk that extends far beyond the legs. PAD is a marker of generalized atherosclerosis. Patients with PAD face 4-5 times higher risk of myocardial infarction and stroke compared to those without peripheral disease.

For athletes—individuals who pride themselves on cardiovascular health—this diagnosis becomes a wake-up call. It opens the door to comprehensive cardiovascular risk assessment, aggressive risk factor modification, and potentially life-saving interventions.

Rethinking Who Needs PAD Screening

The athletic patient with exertional leg symptoms deserves the same diagnostic consideration as the sedentary diabetic with claudication. Both presentations warrant ABI testing. Both patients benefit from early diagnosis.

With tools like simpleABI-Q making screening accessible, quick, and accurate, there’s no reason to delay testing when clinical suspicion exists—regardless of how fit the patient appears.

Sarah eventually underwent revascularization and returned to running, though she now approaches training differently. “I thought being an athlete protected me from vascular disease,” she reflects. “Turns out, being an athlete just made me better at ignoring the warning signs.”

Don’t let your high-performing patients hide their PAD behind impressive race times and exceptional pain tolerance. When exertional symptoms don’t add up, reach for the simplest diagnostic tool available: simpleABI-Q rapid testing.

Because sometimes, the most athletic heart still needs the healthiest arteries to match.