Exercise is often likened to medicine for the heart. Just as with any medication, the effectiveness of exercise depends on the right dosage. A recent study has revealed that this dosage may vary significantly between genders. Specifically, researchers discovered that men require nearly double the amount of exercise compared to women to achieve similar reductions in their heart disease risk.
The study involved over 85,000 UK adults aged 37 to 73, who wore an accelerometer on their wrist for a week. This device measures body movement and activity levels. Following this week, the health outcomes of each participant were monitored for nearly eight years. Such extensive tracking allowed for a comprehensive analysis of how varying activity levels influenced heart health.
The results of the study were striking. Women engaging in about four hours of moderate-to-vigorous physical activity each week—activities like brisk walking, jogging, cycling, or dancing—experienced approximately a 30% reduction in their risk of coronary heart disease. In contrast, men needed to participate in roughly nine hours of the same activities to observe a comparable decline in risk.
Interestingly, these findings extend to individuals already diagnosed with heart disease. The study estimated that women with coronary heart disease needed around 51 minutes of exercise per week to lower their risk of death from any cause by 30%, while men required about 85 minutes.
While these findings may initially seem surprising, they align with long-held beliefs among exercise scientists. A significant reason for these discrepancies lies in biological differences between men and women. For instance, women typically have higher levels of oestrogen, a hormone that plays a crucial role in how the body reacts to exercise. Oestrogen facilitates fat burning during endurance activities and promotes healthy blood vessels by supporting their energy-producing mitochondria.
Moreover, women often possess more slow-twitch muscle fibers, which are efficient and fatigue-resistant, making them better suited for sustained physical activity—the type commonly recommended by exercise guidelines. Thus, while the gap in required exercise minutes might appear startling, it is grounded in biological reality.
The accuracy of this study is noteworthy due to its use of device-measured activity rather than relying on participants’ self-reports, which can often be inaccurate. Importantly, the study still illustrated a graded benefit; more weekly activity correlated with a lower risk of coronary heart disease for both genders. The key takeaway is that everyone benefits from increased physical activity, albeit men may require more to achieve the same heart health benefits.
However, it’s crucial to recognize the study's limitations. Activity was measured over just one week, and the follow-up period of about eight years could allow for other influencing factors, such as menopausal status or hormone replacement therapy, to impact the outcomes. Additionally, the volunteer sample from the UK Biobank study tends to be healthier than the general population, which may limit the generalizability of these findings.
The current exercise guidelines set forth by the World Health Organization, the American Heart Association, and the NHS are sex-neutral. However, this new study challenges these norms, suggesting that exercise recommendations may not be equally effective for everyone. Historically, much of the exercise research has focused primarily on men, leading to assumptions that results apply to women as well.
This revelation is significant as women and men experience heart disease differently, impacting symptoms and outcomes. If the amount of exercise necessary for similar health benefits varies by gender, then exercise guidelines should reflect these differences while remaining straightforward and practical.
It’s essential to clarify that this research does not advocate for women to exercise less or imply that men cannot achieve similar benefits. Instead, it indicates that men may need to engage in more weekly physical activity to attain comparable heart health outcomes. The baseline recommendation of 150 minutes of exercise remains a valuable target, especially as many individuals have yet to meet it.
For men, the focus should not be on simply doubling gym time; instead, they should aim to incorporate more activity into their weekly routines, recognizing that additional minutes will yield greater heart health benefits. Whether different types or intensities of exercise could be more effective for men is an intriguing question for future research.
Both men and women undeniably benefit from regular physical activity, but it is crucial to acknowledge the biological differences that influence how each gender responds to exercise. Current cardiac rehabilitation and exercise referral programs often set identical targets for both men and women. This new study suggests that a more personalized approach may be necessary, tailoring goals to each individual's starting point.
Until such personalized rehabilitation becomes standard practice, the overarching message remains clear: move more and sit less. Strive for the baseline target of 150 minutes of exercise each week, and remember that more activity can lead to even greater health benefits.