Application Of Continuous Glucose Monitoring And Actigraph To Compare The Effect Of Low-carbohydrate Diet And Exercise On Body Weight And Metabolism In Overweight And Obese Adults

Objective: Lifestyle interventions,including dietary adjustment and exercise,are important for weight loss in the context of obesity.This study aimed to compare the effects of a lowcarbohydrate diet(LCD)and exercise on body weight and metabolism in nondiabetic overweight and obese adults.Methods: A total of 45 eligible subjects were randomized into a LCD group(LC,n = 22)and an exercise group(EX,n = 23);either adopted a LCD(carbohydrate intake < 50 g/d)or performed moderate-to-vigorous exercise(? 30 min/d)for 3 weeks.Magnetic resonance imaging and spectroscopy were applied to assess their visceral fat,subcutaneous fat and hepatic steatosis.Flash glucose monitoring(FGM)and actigraphy(AG)covered the whole trial period to measure overall glucose levels and physical activity.Weekly follow-ups were conducted to measure body composition and test fasting blood samples.Subjects came to the last visit 3 days after intervention completion.Results: After 3-week intervention,body weight,body fat content,waist circumference,visceral fat and subcutaneous fat decreased significantly in both groups(all P < 0.05),but the LC lost 2.32 kg more weight than the EX and mainly reduced fat mass and body fluid.Both the interventions improved liver steatosis,liver enzymes and insulin resistance(all P< 0.05).Triglycerides,total cholesterol and low-density lipoprotein-cholesterol(LDL-c)decreased in the EX,while triglycerides decreased and LDL-c increased in the LC(all P <0.05).Glycemic parameters including serum glycated albumin and mean sensor glucose,standard deviations of sensor glucose,coefficient of variability(CV)and largest amplitude of glycemic excursions from FGM data significantly declined in the LC(all P < 0.05).During the intervention period,average daily steps,percentage of daily moderate,vigorous and extreme vigorous physical activity time in the EX were all more than the LC,while only CV slightly decreased after exercise(all P < 0.05).However,body weight and glucose metabolism in the LC rather than EX quickly rebounded after intervention completion.Conclusions: The effects of LCDs and exercise were similar in alleviating liver steatosis and insulin resistance.LCD was more efficient for weight loss and glucose homeostasis in obese people.