The effect of chronic exercise on a biomarker of bone resorption in healthy adults

Background
Long-term exercise contributes to the inhibition of osteoblast cell activity and to the decrease of bone resorption.

Objectives
The research objective was to analyze the chronic effect of regular, long-term physical activity and physical inactivity on carboxyterminal collagen cross-linking telopeptide levels (CTx) and calcium levels in healthy adults.

Material and methods
This study was a prospective cohort study. Fifty-four men and women, aged 17–26 years, were divided into 2 groups of 27 people each: exercise and non-exercise. This research was carried out from April 2015 to April 2016 at the Faculty of Medicine, Syiah Kuala University, Aceh, Indonesia. Bone resorption can be determined by measuring the carboxyterminal cross-linking telopeptide of collagen (CTx). The data were analyzed using Student’s t-test and regression correlation analysis with a significance level of 5%.

Results
The highest levels of CTx were found in the non-exercise group; the lowest levels of CTx were in the exercise group (1.6 ng/mL and 0.30 ng/mL, respectively). This difference in CTx levels between groups was statistically significant (0.52 ± 0.22 ng/mL vs. 0.72 ± 0.28 ng/mL; p = 0.005). Calcium was significantly higher in the exercise group than in the non-exercise one (9.67 ± 0.30 vs. 9.01 ± 0.21 mg/dl; p = 0.006). There was a negative correlation between calcium levels and CTx in the exercise group (r = 0.038; p = 0.001).

Conclusions
Regular exercise led to lower CTx levels and increased calcium levels. The increase in calcium is an effect of the decrease in CTx in healthy adults. Regular exercise decreases bone resorption and increases bone calcium deposition in healthy adults. Regular exercise has the potential to prevent and treat osteoporosis non-pharmacologically.