Strength training tied to lower diabetes risk, beyond cardio

Clinical takeaway: Encourage patients to add strength training to aerobic activity and, more importantly, to keep it up.

Most diabetes-prevention advice centers on aerobic activity, with strength work an afterthought. But a study tracking three large cohorts of US health professionals across decades points to more. The lowest diabetes risk was in those who met both aerobic and strength-training targets while limiting television. Resistance training stayed tied to lower risk even after accounting for aerobic activity.

Resistance training acts on diabetes risk through a different route than cardio. Aerobic exercise improves how efficiently the heart and circulation use oxygen. It also burns glucose during activity. Strength work does something distinct: it builds and preserves muscle, the body's largest site for clearing sugar from the blood. More muscle raises insulin sensitivity over time.

People who trained steadily over the years saw lower diabetes risk even at modest levels, while those who trained sporadically saw little benefit no matter the volume. The pattern held in a trajectory analysis: a consistently high level of training across midlife was tied to a 42% lower risk, while a fluctuating pattern showed none.

Compared with no training, even under half an hour a week was tied to lower risk. The benefit leveled off above roughly an hour weekly rather than climbing with more. Two or more hours a week landed at a 27% lower risk, no better than the one-to-two-hour range.

The largest reduction came from combining behaviors. Meeting the targets for aerobic activity (about 150 minutes a week), strength training (at least an hour a week), and limited television (under two hours a day) was tied to a 62% lower risk than meeting none of the three.

The analysis pooled three long-running US cohorts, the Nurses' Health Study, its successor NHS II, and the Health Professionals Follow-up Study, totaling 143,715 adults followed a mean of 19 years, with about 10,000 developing diabetes. Resistance training and other activity were self-reported and reassessed every two to four years, which let the researchers track patterns rather than rely on a single snapshot. The trajectory analysis drew on NHS II alone.

How widely applicable the data are remains a question. Participants were mostly White health professionals, healthier and more consistent than the average patient, so the effect sizes may shrink in more diverse, less advantaged groups.

"Resistance training among US adult health care professionals was associated with substantially lower T2D risk, particularly when performed consistently over midlife and combined with adequate aerobic activity and limited sedentary television viewing," the authors concluded. "These findings support the inclusion of resistance training as a key component of lifestyle recommendations for diabetes prevention."

Source: Zhang T, et al. JAMA Netw Open. 2026 Jun 22. Long-term resistance training and risk of type 2 diabetes