Exercise meaningfully improves blood sugar in type 2 diabetes, and combining cardio with strength training works best. A meta-analysis in Frontiers in Endocrinology pooled randomized trials to quantify how much different kinds of exercise help people manage type 2 diabetes, both for glucose control and body composition.
Why this matters. Type 2 diabetes is one of the most common chronic conditions worldwide, and while medications are central to treatment, movement is a powerful, low-cost tool. The open question is not whether exercise helps, but how much, and which type delivers the most benefit, which is exactly what pooling many trials can clarify.
What the study did. Researchers searched the major medical databases through May 2026 and combined 16 randomized controlled trials involving 1,401 participants with type 2 diabetes. They used standard meta-analysis methods and assessed each trial's risk of bias with the Cochrane tool, then compared exercise against control across measures of glucose metabolism and body composition.
The effect on long-term blood sugar. Exercise significantly reduced glycated hemoglobin (HbA1c), the standard marker of three-month average blood sugar, with a standardized mean difference of -0.46 (95% CI -0.73 to -0.19). This is a moderate, clinically meaningful improvement achieved through activity alone.
Combined training beat cardio alone. When the researchers split trials by exercise type, combined exercise, aerobic activity paired with resistance training, produced markedly greater improvements in HbA1c (SMD -0.71) than aerobic exercise on its own (-0.32). That is a practical, actionable finding: adding strength work to cardio appears to pay off for glucose control.
Fasting glucose and fitness improved too. Exercise also significantly lowered fasting blood glucose (SMD -0.52) and substantially improved cardiorespiratory fitness, measured as maximal oxygen uptake or VO2max (SMD +0.58). After excluding one outlier study, it also produced a significant reduction in body mass index (SMD -0.37).
One marker that did not budge. Not everything improved. The insulin resistance index did not show a statistically significant change (SMD -0.18), suggesting that within these trials the benefits showed up more clearly in glucose and fitness measures than in this particular index of how well the body responds to insulin.
How to read this. These are pooled results from trials that varied in exercise programs, duration, and participants, so individual results will differ, and standardized mean differences describe the size of an effect rather than a specific point drop in a lab value. The analysis also focused on people already diagnosed with type 2 diabetes, so it speaks to management rather than prevention.
Practical takeaway. For people managing type 2 diabetes, the message is encouraging and specific: regular exercise improves blood sugar and fitness, and a program that blends aerobic activity with resistance training appears to offer the strongest glycemic benefit. As always, anyone with diabetes should coordinate an exercise plan with their care team, especially when medications are involved.
Bottom line. Across 16 trials and 1,401 people, exercise significantly improved HbA1c, fasting glucose, fitness, and body weight in type 2 diabetes, with combined aerobic-plus-resistance training the standout for blood sugar control, reinforcing exercise as a cornerstone of diabetes management alongside medical care.