Mixed
Combining moderate-intensity physical activity with caloric restriction enhances fasting fat oxidation, which is the strongest predictor of improved insulin sensitivity in obese individuals, yielding greater benefits than either intervention alone.
To maximize insulin sensitivity, do not rely on diet or exercise alone. Combine a moderate caloric deficit (500-1000 kcal/day) with regular moderate-intensity exercise (4-6 days/week, 40 minutes, 60-75% max heart rate). This combination significantly outperforms either strategy in isolation by enhancing your body's ability to oxidize fat, which directly drives improvements in how your body handles insulin.
The strongest predictor of the improved insulin sensitivity was enhanced fasting rates of fat oxidation, accounting for 52% of the variance. ... The improvement in the group who combined dieting with exercise, however, was 61%, indicating a threefold higher (P < 0.01) improvement in insulin sensitivity compared with either the exercise-only group or the weight loss–only group.
Why this rating
Randomized controlled trial with matched comparisons, though sample size is modest (n=25 for primary group).
Source
Enhanced Fat Oxidation Through Physical Activity Is Associated With Improvements in Insulin Sensitivity in Obesity
Bret H. Goodpaster et al. · Diabetes · 2003
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