Men who train a lot for years—especially long hours at high intensity—tend to have more plaque in their heart arteries, even if they’re otherwise healthy.
Scientific Claim
In middle-aged and older male endurance athletes and physically active controls, higher objectively measured weekly training duration, particularly when combined with cumulative high-intensity training load (eTRIMP), is associated with a higher prevalence of subclinical coronary atherosclerosis, as detected by coronary CT angiography.
Original Statement
“High training duration (hours/week), particularly when combined with cumulative high-intensity TL (eTRIMP), was independently associated with increased prevalence of subclinical CAD in middle-aged and older athletes and physically active controls.”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The study is a cross-sectional observational design, which can only show association, not causation. The authors correctly used 'associated with' and adjusted for confounders, making the language appropriate.
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.
Systematic Review & Meta-AnalysisLevel 1aWhether the association between long-term high-volume endurance training and subclinical coronary atherosclerosis is consistent across diverse populations and study designs.
Whether the association between long-term high-volume endurance training and subclinical coronary atherosclerosis is consistent across diverse populations and study designs.
What This Would Prove
Whether the association between long-term high-volume endurance training and subclinical coronary atherosclerosis is consistent across diverse populations and study designs.
Ideal Study Design
A systematic review and meta-analysis of prospective cohort studies including at least 10,000 middle-aged and older male endurance athletes and active controls, with at least 10 years of follow-up, using standardized wearable-derived training load metrics and CCTA for atherosclerosis assessment, adjusting for age, lipids, blood pressure, and smoking.
Limitation: Cannot establish causation or rule out residual confounding from unmeasured lifestyle factors.
Prospective Cohort StudyLevel 2aWhether higher training load over time predicts progression of coronary atherosclerosis in athletes.
Whether higher training load over time predicts progression of coronary atherosclerosis in athletes.
What This Would Prove
Whether higher training load over time predicts progression of coronary atherosclerosis in athletes.
Ideal Study Design
A prospective cohort of 500+ men aged 45–65, initially free of CAD, tracked for 10 years with annual wearable-derived training load monitoring and serial CCTA scans to measure plaque progression, adjusting for traditional cardiovascular risk factors.
Limitation: Cannot prove that reducing training load would halt or reverse plaque progression.
Case-Control StudyLevel 3Whether athletes with significant coronary plaque have had significantly higher lifetime training loads than matched athletes without plaque.
Whether athletes with significant coronary plaque have had significantly higher lifetime training loads than matched athletes without plaque.
What This Would Prove
Whether athletes with significant coronary plaque have had significantly higher lifetime training loads than matched athletes without plaque.
Ideal Study Design
A case-control study comparing 200 middle-aged male athletes with CCTA-confirmed significant coronary plaque (cases) to 200 matched athletes without plaque (controls), using retrospective wearable data (if available) or validated longitudinal training logs to estimate lifetime training volume and intensity.
Limitation: Relies on recall or incomplete historical data, susceptible to selection bias.
Randomized Controlled TrialLevel 1bWhether reducing training load in high-volume athletes slows or reverses coronary plaque progression.
Whether reducing training load in high-volume athletes slows or reverses coronary plaque progression.
What This Would Prove
Whether reducing training load in high-volume athletes slows or reverses coronary plaque progression.
Ideal Study Design
A double-blind, placebo-controlled RCT of 150 male athletes aged 50–65 with subclinical CAD, randomized to either maintain high-volume endurance training (>10h/week) or reduce to moderate volume (4–5h/week) for 5 years, with serial CCTA as the primary outcome and wearable-derived TL monitoring.
Limitation: Ethical and practical challenges in blinding and long-term adherence; unlikely to be conducted.
Cross-Sectional StudyLevel 4In EvidenceThe current association between training load and plaque burden at a single point in time.
The current association between training load and plaque burden at a single point in time.
What This Would Prove
The current association between training load and plaque burden at a single point in time.
Ideal Study Design
A cross-sectional study using wearable devices to measure 12 months of training load and CCTA to assess plaque burden in 200+ middle-aged male athletes and controls, as performed in this study.
Limitation: Cannot determine directionality or temporal sequence; cannot assess progression or causation.
Evidence from Studies
Supporting (1)
This study found that older male athletes who train a lot, especially with intense workouts, are more likely to have early signs of heart artery plaque — even if they’re otherwise healthy — and this was measured accurately with wearables, not just self-reports.