A major study tracking over 111,000 health professionals for more than 30 years has found that people who engage in multiple types of physical activity have a lower risk of premature death, even after accounting for the total amount of exercise they do. The research, published in BMJ Medicine, suggests that variety in physical activity may offer health benefits beyond simply exercising more.
The Study at a Glance
Researchers from Harvard’s T.H. Chan School of Public Health analyzed data from two long-running studies: the Nurses’ Health Study, which followed 70,725 women from 1986 to 2018, and the Health Professionals Follow-Up Study, which tracked 40,742 men from 1986 to 2020. Participants reported their physical activity every two years, providing up to 15 repeated assessments over the study period.
During approximately 2.4 million person-years of follow-up, the researchers documented 38,847 deaths, including 9,901 from cardiovascular disease, 10,719 from cancer, and 3,159 from respiratory disease.
Key Findings
Most activities are linked to lower mortality. The study examined nine common physical activities: walking, jogging, running, bicycling, swimming, tennis or squash, climbing stairs, rowing, calisthenics, and weight training. All of these activities, except swimming, were associated with statistically significant reductions in all-cause mortality when comparing the most active participants to the least active in each category.
Walking showed the strongest and most consistent benefits, with the most active walkers having a 17% lower risk of death compared to those who walked the least. Tennis, squash, or racquetball players in the highest activity group had a 15% lower mortality risk, while those who engaged most in rowing or calisthenics saw a 14% reduction.
Benefits plateau at moderate levels. The relationship between exercise and mortality was not linear for most activities. The mortality reduction from walking, for instance, largely plateaued after about 7.5 MET-hours per week, which translates to roughly 2.5 hours of brisk walking per week. For stair climbing, the benefits leveled off at about 0.75 MET-hours per week, equivalent to climbing approximately five flights of stairs daily.
Variety matters independently. Perhaps the most novel finding was that engaging in multiple types of physical activity provided additional survival benefits beyond the total volume of exercise. After adjusting for total physical activity levels, participants with the highest variety scores had a 19% lower risk of all-cause mortality compared to those with the lowest variety scores. The benefits extended to specific causes of death as well, with reductions of 17% in cardiovascular disease mortality, 13% in cancer mortality, and 41% in respiratory disease mortality.
Why Variety May Matter
The researchers hypothesize that different types of physical activity affect the body in distinct ways. Aerobic exercises like walking and running improve cardiorespiratory fitness and oxygen consumption, while resistance training builds muscular strength and helps preserve bone density. Racquet sports may enhance coordination and reaction time, and activities like swimming provide low-impact cardiovascular conditioning.
Previous intervention studies have shown that combining aerobic exercise with resistance training produces improvements in multiple health domains that neither type of exercise achieves alone. A 26-week trial in older adults with obesity found that aerobic exercise produced greater gains in cardiovascular fitness, while resistance training better preserved muscle mass and bone mineral density. Participants who did both types of exercise enjoyed benefits in both areas.
By engaging in multiple activities, individuals may be able to capture the unique physiological benefits of each without overdoing any single type. The study authors note that the health benefits of most individual activities plateaued at certain thresholds. Diversifying one’s exercise routine can help people maximize gains across different health dimensions while staying within the beneficial range for each activity.
Practical Implications
The findings reinforce existing public health recommendations to incorporate both aerobic and strength-training activities into weekly routines. Current guidelines from the U.S. Department of Health and Human Services recommend at least 150 minutes of moderate-intensity aerobic activity per week, along with muscle-strengthening activities on two or more days.
This study suggests there may be additional value in going beyond these two categories to include a broader range of activities. Someone who currently walks and lifts weights might consider adding tennis, cycling, or swimming to their routine. The key message is not that more exercise is always better, but that a diverse portfolio of activities may be more beneficial than focusing intensively on just one or two types.
The non-linear dose-response relationships also carry practical significance. For many activities, substantial benefits were achieved at relatively modest levels of participation. This may be encouraging news for people who feel they cannot commit to intensive exercise programs. Even moderate engagement in several different activities could yield meaningful health benefits.
Study Limitations
The research has several important limitations. Participants were predominantly white health professionals, so the findings may not generalize to other populations. Physical activity was self-reported, which introduces the possibility of measurement error. The observational design means the study can only identify associations, not prove that exercise variety directly causes lower mortality. People who engage in diverse physical activities may differ in other health-related behaviors that the researchers could not fully account for.
The finding that swimming was not associated with all-cause mortality deserves particular attention. The researchers suggest this may reflect measurement issues. Self-reported swimming duration may not accurately reflect energy expenditure because people swim at widely varying intensities. Someone who swims laps vigorously and someone who swims casually may report similar durations despite very different levels of exertion.
The Bottom Line
This study adds to growing evidence that an active lifestyle promotes longevity, while offering new insights into how the type and variety of activities may matter. The practical takeaway is straightforward: rather than focusing exclusively on one form of exercise, consider building a routine that incorporates multiple activities. Walking, strength training, and a recreational sport or two may offer more protection than intensive commitment to a single activity alone.
The findings also suggest that the bar for meaningful benefit may be lower than many people assume. You do not need to train like an elite athlete. Consistent, moderate engagement in several different activities appears to be a sound strategy for supporting long-term health.
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