Researchers from Kitasato University reported a striking link between leg strength and the likelihood of developing heart failure after a heart attack. Presented at a European Society of Cardiology scientific congress, the findings suggest that robust leg muscles may serve as a protective factor against heart failure in patients who have experienced a myocardial infarction.
Myocardial infarction stands as the leading trigger for heart failure, with estimates indicating that 6 to 9 percent of those who survive a heart attack go on to develop heart failure. Previous studies have noted that stronger quadriceps muscles are associated with improved survival in individuals with coronary artery disease. In this investigation, researchers explored whether leg strength performs a similar protective role specifically for heart failure risk following an acute myocardial infarction.
The analysis drew on a cohort of 932 individuals who were admitted to the hospital for acute myocardial infarction between 2007 and 2020 and who did not have heart failure at the time of admission. The median age of participants was 66, and the group was predominantly male, comprising 81 percent of the sample. This sizable, long-term observation allowed the team to examine how physical capability, measured soon after the event, might relate to subsequent cardiac outcomes.
To quantify leg strength, researchers used maximum quadriceps strength as the key metric. Participants sat in a chair and maximally contracted their quadriceps muscles for five seconds while an ankle-mounted dynamometer captured the peak force in kilograms. Measurements were taken on both legs and then averaged to yield an overall strength score for each participant. This approach provided a practical, clinical way to gauge leg power that could be replicated in routine practice.
The quadriceps strength values were subsequently expressed relative to body weight. On average, women exhibited leg strength equal to about 33 percent of their body weight, while men averaged around 52 percent. Over an average follow-up period of roughly four and a half years, heart failure developed in 67 participants, corresponding to 7.2 percent of the cohort. When comparing individuals with higher leg strength to those with lower strength, the data showed a meaningful association: greater quadriceps power correlated with a markedly lower risk of heart failure, with a 41 percent reduction observed among those with stronger legs. In addition, each incremental 5 percent increase in quadriceps strength, as a proportion of body weight, was linked to an approximately 11 percent drop in the risk of heart failure.
These findings imply that simple, reliable measurements of leg strength could become a valuable element of post-heart attack care. If clinicians can readily assess quadriceps power, they may better identify patients who are at heightened risk for developing heart failure and who could benefit from closer monitoring or targeted rehabilitation strategies. The researchers emphasized that replication in other patient groups is essential to confirm the results, but the study also hints at a practical intervention: incorporating strength training focused on the quadriceps into post-infarction rehabilitation programs might help prevent heart failure in some patients.
Beyond the immediate clinical implications, the study invites a broader conversation about physical function as a prognostic indicator in cardiovascular disease. It underscores the potential value of integrating simple, objective measures of lower-limb strength into standard post-MI care pathways. If future trials corroborate these observations, health systems could consider structured leg-strengthening programs as part of comprehensive recovery plans, alongside medical therapy and lifestyle modification. In this light, leg power becomes more than a marker of current function; it emerges as a modifiable factor with real implications for long-term heart health.