The effects of short-term combined exercise training on telomere length in obese women: a prospective, interventional study

Background

Telomere length is inversely associated with the senescence and aging process. Parallelly, obesity can promote telomere shortening. Evidence suggests that physical activity may promote telomere elongation.

Objective

This study’s objective is to evaluate the effects of combined exercise training on telomere length in obese women.

Design and Methods

Twenty pre-menopausal women (BMI 30–40 kg/m², 20–40 years) submitted to combined training (strength and aerobic exercises), but only 13 finished the protocol. Each exercise session lasted 55 min/day, three times a week, throughout 8 weeks. Anthropometric data, body composition, physical performance (Vo_2max), and 8-h fasting blood samples were taken before and after 8 weeks of training. Leukocyte DNA was extracted for telomere length by RT-qPCR reaction, using the 2^−ΔΔCt methodology.

Results

After the training intervention, significant differences (p < 0.05) were observed in telomere length (respectively before and after, 1.03 ± 0.04 to 1.07 ± 0.04 T/S ratio), fat-free mass (46 ± 7 to 48 ± 5 kg), Vo_2max (35 ± 3 to 38 ± 3 ml/kg/min), and waist circumference (96 ± 8 to 90 ± 6 cm). In addition, an inverse correlation between waist circumference and telomere length was found, before (r = − 0.536, p = 0.017) and after (r = − 0.655, p = 0.015) exercise training.

Conclusion

Combined exercise promoted leukocyte telomere elongation in obese women. Besides, the data suggested that greater waist circumference may predict shorter telomere length.

Clinical Trial Registration

ClinicalTrails.gov, NCT03119350. Retrospectively registered on 18 April 2017

Physical training, UCP1 expression, mitochondrial density, and coupling in adipose tissue from women with obesity

BACKGROUND

Exercise training may improve energy expenditure, thermogenesis, and oxidative capacities. Therefore, we hypothesized that physical training enhances white adipose tissue mitochondrial oxidative capacity from obese women.

OBJECTIVE

To evaluate mitochondrial respiratory capacity, mitochondrial content, and UCP1 gene expression in white adipose tissue from women with obesity before and after the physical training program.

METHODS

Women (n = 14, BMI 33 ± 3 kg/m² , 35 ± 6 years, mean ± SD) were submitted to strength and aerobic exercises (75%-90% maximum heart rate and multiple repetitions), 3 times/week during 8 weeks. All evaluated subjects were paired, before and after training for resting metabolic rate (RMR), substrate oxidation (lipid and carbohydrate) by indirect calorimeter, deuterium oxide body composition, and aerobic maximum velocity (V_max ) test. At the beginning and at the ending of the protocol, abdominal subcutaneous adipose tissue was collected to measure the mitochondrial respiration by high-resolution respirometry, mitochondrial content by citrate synthase (CS) activity, and UCP1 gene expression by RT-qPCR.

RESULTS

Combined physical training increased RMR, lipid oxidation, and V_max but did not change body weight/composition. In WAT, exercise increased CS activity, decreased mitochondrial uncoupled respiration and mRNA of UCP1. RMR was positively correlated with fat-free mass.

CONCLUSION

Physical training promotes an increase in mitochondrial content without changing tissue respiratory capacity, a reduction in mitochondrial uncoupling degree and UCP1 mRNA expression in WAT. Finally, it improved the resting metabolic rate, lipid oxidation and physical performance, independent of the body changing free, or fat mass in obese women.