Strength training ACM is an emerging question for people with arrhythmogenic cardiomyopathy, families, coaches, and exercise professionals who want to understand what current evidence can and cannot say. The topic deserves caution because ACM is not simply a general fitness concern. It is a heart muscle condition associated with arrhythmias, and exercise decisions may vary based on diagnosis, symptoms, genotype, prior arrhythmia history, cardiac imaging, medications, implanted devices, and clinician judgment.
This is educational information, not medical advice or an exercise plan. Anyone with diagnosed ACM, suspected ACM, a family history of ACM, or a known gene variant linked with ACM should discuss activity with a cardiology team familiar with inherited heart disease and sports cardiology when possible.
Why Strength Training ACM Needs Caution
What ACM Means For Exercise Decisions
Arrhythmogenic cardiomyopathy has been described in the research record as affecting about 1 in 5,000 people. The condition can involve electrical instability of the heart and structural changes over time. Because those features differ from person to person, exercise guidance is not well served by a single public rule that applies to everyone.
The American Heart Association scientific statement on exercise training in high-risk populations places ACM among conditions where exercise decisions require careful risk consideration, and it reports the approximate 1 in 5,000 prevalence estimate for ACM AHA scientific statement. That does not mean movement is automatically off limits. It does mean the type, intensity, duration, and competitive setting may matter.
Strength Training ACM Is Not A Free Pass
Strength training ACM discussions can become oversimplified if people hear “resistance exercise may be safer than endurance exercise” and translate that into “all lifting is safe.” The available research does not support that leap. Resistance exercise can range from light supervised movements to very heavy lifting, maximal strain, breath-holding, high-pressure competitive events, climbing, martial arts, or mixed training that also includes vigorous endurance work.
For a person with ACM, the question is not only whether an activity is labeled strength training. The more relevant questions may include how hard the effort is, how long sessions last, whether the person also performs vigorous aerobic exercise, whether symptoms occur, and whether the plan has been reviewed against that person’s risk profile.
What Current Statements Say About Exercise Risk
Endurance Volume Is The Repeated Concern
Across the research notes, high-volume and high-intensity endurance activity is the most consistent concern. The 2026 ACC scientific statement specifically says that “exercise volume in excess of recommended levels and endurance exercise may accelerate disease progression and arrhythmic risk” in people with ACM ACC scientific statement. That language is cautious, but it is also direct.
Other expert guidance summarized in the research notes has discouraged vigorous exercise for ACM, especially in competitive sports participants or people with higher-risk genotypes such as PKP2. For patients with definite ARVC, a subtype of ACM, high-intensity recreational exercise and competitive sports have been described as not recommended. Low- to moderate-intensity recreational activity may be considered for some people, depending on individual risk factors.
Why Individual Risk Assessment Matters
The European Society of Cardiology’s 2023 guidance, as summarized in the research, called for individualized risk assessment before exercise prescription in cardiomyopathy. That principle is central here. Two people with the same broad diagnosis may not have the same arrhythmia history, imaging findings, gene variant, symptoms, family history, or training background.
Genotype-positive but phenotype-negative individuals create another careful category. The research notes report that high-intensity endurance exercise has been associated with a greater likelihood of developing an overt ACM phenotype and ventricular arrhythmias in genotype-positive, phenotype-negative ARVC. That does not answer every question about light or moderate resistance exercise, but it supports the need for genotype-informed counseling rather than generic fitness advice.
What The 2026 Strength Training Study Suggests
How The Groups Differed
A retrospective study published on September 10, 2026, in JACC: Clinical Electrophysiology compared exercise patterns among 355 people in the Johns Hopkins ARVC Registry. The median age was 34. According to the research summary, about 55% reported mixed endurance and strength training, 26% were sedentary, 12% performed endurance-only exercise, and 7% performed strength-only exercise.
The study defined endurance athletes as people reporting at least 4 hours per week of vigorous aerobic exercise. Strength-only athletes reported at least 2 hours per week of resistance exercise, climbing, or martial arts. In that analysis, endurance athletes had a significantly increased risk of sustained ventricular arrhythmia. Strength-only athletes did not show a significant increase in risk compared with sedentary controls.
What The Findings Cannot Prove
That finding is meaningful, but it should be read with restraint. Strength training ACM evidence from a retrospective registry study can suggest associations; it cannot prove that any particular resistance routine is safe for every person with ACM. The strength-only group was also a small share of the cohort, which limits how much certainty can be drawn for different ages, genotypes, disease stages, lifting intensities, or competitive settings.
The same research summary reported that lifetime ventricular arrhythmia risk was higher in the combined endurance groups than in the strength-only plus sedentary groups. It also reported that exercise volume declined after registry enrollment: average aerobic activity fell from about 6 hours per week before enrollment to about 2 hours per week a few years later, while strength training declined from about 2.75 hours per week to under 1 hour. Those changes may reflect adoption of recommendations against high-intensity aerobic activity, but they also make interpretation harder because people changed behavior over time.
Practical Conversation Points Before Resistance Exercise
Intensity, Symptoms, And Supervision
People often ask whether resistance training is “allowed.” A safer question is what level and type of activity has been reviewed for the person’s clinical situation. A clinician may want to discuss intensity, repetition range, breath-holding or straining, competitive goals, symptom history, device considerations, family history, and whether the person is also doing vigorous endurance sessions.
- Ask what intensity range is considered reasonable for your specific risk profile.
- Ask whether heavy straining, maximal lifts, or competitive lifting should be avoided.
- Ask what symptoms should prompt stopping activity and seeking medical evaluation.
- Ask whether supervised cardiac rehabilitation, sports cardiology input, or genetic counseling is appropriate.
- Ask how exercise guidance should be updated if imaging, rhythm monitoring, symptoms, or medications change.
These questions do not replace clinical care. They can help organize a visit so the discussion is specific rather than limited to broad reassurance or broad restriction.
Community Support Without Overreach
Strength training ACM decisions can affect identity, routine, confidence, and social connection. Someone who has been advised to reduce endurance exercise or stop competitive sport may need help finding forms of movement that feel meaningful while staying within professional guidance. That support can come from clinicians, family, trainers who respect medical boundaries, and community programs that avoid pressure-based fitness culture.
For broader wellness conversations around time pressure, rest, and community choices, Take Back Your Time offers a resource on managing daily demands and how they can influence health behaviors. On this site, readers may also find related context in exercise prescription and heart health guidance, especially the idea that exercise planning in cardiovascular care should be discussed with qualified professionals.
How To Read Safety Claims About ACM
Words Like Safer Still Need Context
If a headline says strength training is not linked with ventricular arrhythmia in ACM, that does not mean every resistance activity is low risk. It means that, in a specific retrospective cohort and under the study’s definitions, strength-only athletes did not show a significant increased risk compared with sedentary participants. That is encouraging for future research and clinical discussion, but it is not the same as a universal clearance.
Evidence also points away from frequent, vigorous endurance exercise in ACM and ARVC, particularly for competitive athletes and some genotype groups. For people who enjoy training, that can be difficult to accept. Still, a shift from high-intensity endurance toward lower-intensity or carefully reviewed resistance activity should be guided by clinical information rather than personal trial and error.
Training Labels Can Hide Mixed Exposure
Another reason to be cautious is that many people do not train in one category. Circuit training, climbing, martial arts, CrossFit-style sessions, team conditioning, and gym classes may combine resistance work with high heart-rate endurance demands. A person may think they are doing strength work while the session functions partly as vigorous aerobic training.
That distinction matters because the available research repeatedly points to endurance volume and intensity as risk signals in ACM. Describing actual sessions in detail may help a clinician understand the real exposure: duration, rest periods, heart-rate response if monitored, perceived exertion, competitive setting, and weekly total.
Strength Training ACM Questions For Your Clinician
Strength training ACM may become a more nuanced option for some people than high-intensity endurance exercise, but the evidence is not a stand-alone permission slip. The most defensible reading is cautious: resistance-focused activity showed no significant increased arrhythmia risk in one recent retrospective analysis, while high-intensity endurance exercise has been linked more consistently with ACM progression and arrhythmic risk.
Before starting, resuming, or changing resistance exercise, consider asking your clinician: What is my current ACM risk profile? Do my genotype, imaging, rhythm history, symptoms, or family history change your advice? Are there intensity limits I should follow? Should I avoid maximal efforts, breath-holding, competition, or mixed high-intensity conditioning? What changes should lead me to stop activity and contact the care team?
Those questions keep the focus where it belongs: not on proving toughness, but on making informed decisions with people who know your medical history.
